Is one able to "override" the terms of the Youtube Standard Licence with a slightly stricter Creative Commons than is allowed by the interface?

Don't do it

As @Mulvya mentioned, it is not a good idea to attempt to 'overwrite' the CC licence set in the video settings by putting a disclaimer in your video or video description. Apart from the legal implications and ambiguity, there's another problem: You're only changing the human-readable layer of the licence, while the machine-readable layer stays the same (an explanation on the three layers of the CC licences can be found here). What that means is that even though a human watching your video will be able to understand your intent to apply a more restrictive licence, a machine (e.g. an automated web crawler) will not. So your video will still show up in the search results when somebody searches for content licenced under the CC-BY licence. So by setting your video to CC-BY and disputing that claim in your video or video description, you are creating ambiguity for the user. I also doubt a disclaimer that the licence set by you in the YouTute interface does not apply would hold up in court, but IANAL.

Alternative

Hosting your video on YouTube with the intent to share it for others to adapt, remix and reuse is not a good idea in the first place. The stark compression applied by YouTube will significantly lower the quality of your video. The quality loss will only increase as others download your video, import it into their own projects, reencode it again and upload it to YouTube, where it's reencoded once more. On top of that, YouTube doesn't even offer a convenient way to download user-uploaded videos (though you can use them in YouTube's own video editor, but hardly anyone uses that anyway ...). For more information on YouTube's video compression, read my answers here and here.

Instead, I suggest you upload a high-quality version of your video to a dedicated file hosting service and put your licence terms there. You can also bundle your video file with a text-file containing a description of your licence terms and a link to the online licence. This eliminates all ambiguity and allows everyone to use your video under clearly-defined terms.

If you do this, put a link to the downloadable version of your video in your video description. Also, make sure to select the YouTube Standard Licence for this video. This allows users access for only private, non-commercial viewing purposes (see YouTube terms section 6). This way, you can make sure there's no ambiguity regarding your licence terms. As a sideeffect, this will point people towards the high-quality version, meaning nobody will use a low-quality version ripped from YouTube, in case you care about that.


Cannot capture (HDMI) output of Graphics Card with BlackMagic UltraStudio

What solved the problem:

Check your capture software settings. All settings (your monitor/capture device settings, your hardware settings and the settings in your capture software) should be correct and equal.

What can help track down similar issues:

Very likely a framerate issue. Only the 4K version of the Blackmagic Capture cards supports 60FPS and your monitor is or was probably set to 60Hz or 50Hz, though your capture card probably is only supporting 30FPS @ 1080p (assuming thats your resolution). (Edit: In this case not true, the UltraStudio (4k) does support 60fps even at 4k over SDI but if someone else has this issue, have a look at the specs of your capture card)

Assuming your are using Windows go to the resolution settings and click on advanced settings after selecting the capture card "display" and then go to the "Monitor" tab and select a lower refresh rate like 30FPS or 25FPS. Then set the same refresh rate in your capture settings.

On a Mac you can use a tool called SwitchResX to change your refreshrate or alternatively in your case simply set your capture settings to the output settings shown in the System Informations for the Capture Card "display". So same resolution and refresh rate.

If your really unlucky your Mac doesn't recognize the UltraStudio as a display or the Ultrastudio isn't sending any EDID information, though I somewhat doubt that's the case. I had this issue all the time with the 4K PCI-E capture card from Blackmagic, it always was a settings mismatch.

Also make sure that if you want to capture a video that's playing back, it isn't protected by HDCP like Jim Mack suggested.


Different rate distortion curves for two videos encoded with same parameters in FFMPEG

The difference in the content of the two samples could explain the different performance of the codec. A given configuration of a codec might perform well for a static shot but not perform well for fast motion. At higher bit rates, the effects of codec settings are usually less noticeable.


Stream Screen from one machine and webcam from another

Looks a lot like  share desktop to laptop to stream from laptop  (that guy's goal was lower CPU load on his desktop, but same solution.)

Use the usual streaming setup on your desktop, but with high bitrate.  stream to laptop, decode there.  overlay webcam, encode for normal streaming, send that output to Twitch.tv.

IDK what it takes to send streams to twitch, or to receive streams from desktop streaming software.  Assuming you can get ffmpeg to do it, and read from your webcam, use the overlay filter to combine the streams, and -c:v libx264 -preset medium to encode to h.264.  Not sure what you'd need to do to get ffmpeg's output to go to Twitch.tv.


Unlink two layers after a certain time in After Effects

valueAtTime returns the keyframed value of the property, before any expression is applied.

change it to:

p = thisComp.layer("Leader").transform.position;
t = 1; // Stop following after 1 second
if (time <= t) {
    value + (p.value - p.valueAtTime(0));
}
else {
    value + (p.value.valueAtTime(t) - p.valueAtTime(0));
}

or more simply:

p = thisComp.layer("Leader").transform.position;
t = Math.min(time, 1); // time increases until it hits 1, then stays there
value + (p.value.valueAtTime(t) - p.valueAtTime(0));

This avoids the if() statement which means it should evaluate faster.


Extract section from Premiere without re-compression

I know this is an old question abandoned by the asker, but I use ffmpeg to stream copy (re-mux) sections.

Example 1: Single output

Skip first 14 minutes and make a 30 second output:

ffmpeg -ss 00:14:00 -i input -t 30 -c copy -map 0 output

This will not re-encode, so the process is quick and preserves the quality.
Depending on your input format the output may not be exactly from the desired time, but usually it's close enough. See the -ss option in the FFmpeg documentation for more info.

Example 2: One segment of every n seconds

Use the segment muxer:

ffmpeg -i input -c copy -map 0 -segment_time 30 -f segment output%03d.foo

This will not re-encode, so the process is quick and preserves the quality.
Note that splitting may not be accurate, unless you force the reference stream key-frames at the given time. See the segment muxer documentation for more info.


Why is the alignment setting disabled on my Constant Power audio transition?

I had the same issue. For me, there was a very small gap between the 2 clips, which was not visible until I expanded the time sequence to a greater extent. Once I remove the gap between clips, alignment got enabled for me


Combine audio and video file without creating a 3rd file

I found a solution to my problem:

Ffmpeg can use a http stream as input:

ffmpeg -i YoutubeVideoOnlyURLHere -i YoutubeAudioOnlyURLHere -c copy -map 0:0 -map 1:0 Path/to/outputFile.mp4

You can get the needed URLs from
youtube-dl -f bestvideo,bestaudio --get-url https:www.youtube.com/watch?v=XXXXXXXXXXX


Is it possible to find a webcam with large aperture?

Actually, your best bet is to use a PCIe or USB 3.0 HDMI input card, like a Blackmagic Intensity, which will take the clean HDMI output of many high quality cameras (e.g: a Nikon D600 or D800, a Canon C100 or C300, etc.) and make it available to other apps on your computer. This is what professional productions do for green screen work to ensure they're getting the full quality image out of the camera before it hits the camera's compression software.


How do I temporarily disable Davinci Resolve nodes?

⌘-D will disable the currently selected node.  Resolve really doesn't like to have loose nodes floating around, so either disable them, or delete them.  But since you're talking about creating a new, experimental node structure, what you really want to do is create a new local version.  Right click on the clip thumbnail and select Local versions-> create new version.  This basically creates a copy of your node structure that you can return to whenever you like.  After issuing the command, you'll see that the name of the new version appears under the thumbnail to let you know which one you're working on.  To revert to the original (or select from any number of alternate versions), right click the thumbnail again and choose versionName->Load.


FFmpeg : How to replace video background color with transparency? (while capturing)

GDIgrab supplies a RGB feed so the colorkey filter can work here.

Try

ffmpeg -i 1.mp4 -f gdigrab -framerate 25 -video_size 300x200 -i title="MyWindow"
-filter_complex
"[1]split[m][a];
 [a]format=yuv444p,geq='if(gt(lum(X,Y),0),255,0)',hue=s=0[al];
 [m][al]alphamerge[ovr];
 [0][ovr]overlay=(main_w-overlay_w):main_h-overlay_h[v]"
-map "[v]" -c:v libx264 -r 25 out.mp4

You may have to use a value of near 0, if 0 doesn't capture all the transparent area.


Which software a dubbing studio use for subtitles and closed captioning workflow?

Most episodic (network and cable) TV is captioned by service bureaus who use proprietary software. Some of the big players are VITAC, NCI, and WGBH, and there are several more. They all provide various levels of service, and some rely more heavily on automation / voice recognition etc than others. This is all offline captioning and the goal is accuracy in copy, placement and timing.

The other main thread (and skill) is live writing or real-time captioning, which is done with stenowriters (chord typing) as used by court reporters. These are always delayed by some time because of the need to hear, interpret and input. It's almost always done remotely, with the caption writer networked into a local encoder. The same bureaus usually offer both live and offline.

To learn more, check out the links above -- and google for more -- then maybe contact the providers that look interesting to you.


Hardware requirements for multiple TV channels (cable TV) digitization

I'm assuming you're talking about digital cable, since it's 2012.

The way this works is that your equipment tunes into a frequency over which a multiplex is broadcast. That's a digital stream that can be demultiplexed into a number of sub-streams. Each sub-stream is a TV channel.

There are standards for these things. The sensible thing to do (especially since they're unencrypted channels) is to use DVB receiver cards in a PC. I'd use Linux, but it's up to you.

You mention archiving these at "low quality". The problem here is that the channels are broadcast at a given quality, and the broadcaster has already done the hard work of digitising and compressing the content. If you want to lower the quality, you'd have to demultiplex, decompress, scale, and compress, and that's a lot of processing. Compression is especially expensive in terms of processing.

Since storage is cheap, and getting cheaper, I'd suggest storing the streams exactly as they arrive. This is what DVRs (e.g. Sky+, digital TiVo etc. do).

You have a choice between demultiplexing, and storing the streams you want individually -- or simply writing the whole multiplex to disk. Demultiplexing is cheap; but not as cheap as simply dumping every byte the tuner supplies you onto disk. Demultiplexing, of course, allows you to pick and choose which channels to discard.

I'm afraid my 2 minutes of Googling didn't reveal what the bit rate of a cable TV multiplex is - but it shouldn't be difficult for you to find out. Once you know that, it's simple sums to work out how quickly you'll fill disks, and what kind of sustained write speed you'll need.

There is free software available to drive DVB cards. One example is OpenDVB. It would be worth doing some reading around the MythTV community. Although they'll be focussed one or two channels at a time, they'll know their way around the technology, and the software is modular.

You'll need a DVB card for each multiplex you're recording, since each one can only tune to one frequency. Depending on what you discover about bit rates, it may be worth splitting the task between several computers - but in theory one computer can have multiple DVB cards.

As a vague guide on CPU power - reading from the tuner and demultiplexing take negligible amounts of CPU work. Any PC CPU of the last 10 years could do it without breaking a sweat. Encoding/compressing is really hard work. A top-end modern CPU has trouble compressing SD video in real time. To do it at all efficiently, you'd have to offload it to dedicated chips (which is how camcorders etc. manage it).


FFMPEG: Transparent background with 'showwaves' or 'showspectrum'

The default codec for MP4 is x264 which does not support alpha channel. Use PNG.

ffmpeg -i music.mp3 -filter_complex \
"[0:a]showwaves=s=1920x1080:mode=line:colors=white:draw=full,format=rgbap[v]" \
-map "[v]" -map 0:a -c:v png output.mp4;


I've just received an answer on another forum:

Select "DaVinci Resolve" from the main menu, select "Preferences"
In the media storage tab press "+" and select the desired folder / drive.
Press OK and restart DaVinci.

OK, this software is definitely not intuitive, and one should not read the first 100 pages of the manual too fast!


What are the most common project formats for modern NLE software?

Those are the three that are industry standard, XML is a useful one to include though because Final Cut (which oddly is still highly utilized in the industry) uses it.  Also XML can easily talk between all Adobe applications and Da Vinci.


How do I export vertical video in Adobe Premiere CC?

In Premiere Pro, if you change your sequence size to match your source, you can export the vertical video that way. In the project panel, right click your sequence and change the frame size to the frame size of your video.

You can then export with the preset of Match Source (the bitrate depends on your project needs).

Additionally, you can also export the video with the preset of your choosing. Uncheck the "Width and Height" and type in the appropriate resolution (example is below).


What you are referring to is called hot linking, and while it may or may not technically be a violation of their copyright or terms of use (check their website for details) it is still generally considered a poor practice since you are effectively utilizing their bandwidth without mentioning that it is their bandwidth.

Your best bet is to contact the operators of those cameras and ask them what they think.


How to get Greek symbols (alpha, beta) in Cinema4D text

I can't be 100% certain, but the problem is most likely your font type.  I'm not familiar with Cinema4D specifically, but some fonts are raster based for given point sizes and some are vector based.  Most extrusions require you to have a vector based format and if the font is raster, then you aren't going to get any result.

The best bet is either to find a vector based greek font or to use something like illustrator to create a vector path that fits the characters and import that vector document for extrusion.


How to record live video using camcorder?

Perhaps the Intensity Shuttle from Blackmagicdesign

http://www.blackmagicdesign.com/products/intensity/models/

This link has some additional info.

http://help.livestream.com/customer/portal/articles/577891-what-are-your-recommended-devices-


Specify a custom "Movie rec. size" on Canon Rebel

Short answer: no. The presets you get are what you are stuck with.

If you can do 1920x1080 at 30fps, it's easy enough to use a video editor or converter to go down to 1280x720 with minimal loss.

I frequently would record at 1080p on a Canon DSLR, and then finish and render at 720p (with the same framerate).


How do I download FFmpeg build for windows 7 64 bit? (Zeranoe’s are offline.)

The msg for gyan.dev downloads is a false alarm. All files are delivered via HTTPS. Select Keep instead of Discard.
Chrome shows the same message for Google Earth downloads as well.
This is apparently an initiative by Google to ultimately prevent mixed content downloads in Chrome.


A player doesn't have to acknowledge the position of subtitles. So a user could re-position them if he wanted to.
Thats actually the standard way of doing it. What you have there is a custom tag. The .srt format doesn't include any position data for the subtitles. Some players can recognize this sort of custom data and use it but you can't expect that a player will understand it.


Automating Adobe Premiere Pro for trimming videos based on volume level

Try the Auto Gate setting in the Dynamics audio effect.
It will gate (turn off the audio) if the threshold of the audio falls below a specified level for a specified amount of time.
Doing this manually would sound better but take longer.
The gate won’t be able to tell the difference between a deliberate piece of speech and a mouth pop or click, so you may hear the gate open and close when you don’t want it to.

https://helpx.adobe.com/in/premiere-pro/using/audio-effects-transitions.html

Note:It will not trim your clips, just affect whether you hear parts of them in your edit.


That was possibly achieved by taking a picture from several different angles simultaneously with multiple cameras. You can then flip through the images like a flip book.

You can simulate this by taking a single still image and separating out the foreground (the people in this case) from the background. For example, in Photoshop you could use any selection method you want - lasso, pen tool, quick mask, etc. - to select the people. Cut them out and put them on another layer. Next, turn them off and fill in the area where they used to be with something believable. This is a case where content-aware fill comes in handy. Turn the layer with the people back on. Import the photo into any motion graphics application, but be sure to import it as separate layers and not a composite. Once in the app, move the people towards the camera and/or move the background away from the camera. Once there's some separation you can orbit the 3D camera around the image a little bit. If you go too far, it will become obvious that the people are a 2D cut-out, so be careful with how far you take it.

You can also apply lights to the image in the motion graphics application. That should help you get a look similar to what you saw in the link.


video player that runs videos from pointed directory and updates list of files to play while new file appears in directory

Serviio is really good. It has a free and paid option. The free version is great.

http://serviio.org/


How can you fix color banding from VHS video tape in post-processing?

Neat Video has been working miracles on footage for us so far, you can give the trial a go! We've never tried it on this specific artifact (that I know of) but it does have features for restoration/archival type damage, and I highly recommend it.


Maybe you have changed the system playback volume by clicking the sound icon in the Properties pane.

You can change the volume of (and mute) any layer or range by using the Adjust Volume tool in Timeline as shown in below image.


Auto upload (ftp) video file once it's finished encoding

Maybe someone will chime in with an app suggestion that directly fulfills your need, but here's a temporary workaround - a bit convoluted, but should work.

Create two folders A and B.
Set folder A as the destination folder in the encoder.
Apply a suffix to all the output files being generated, something innocuous like ENC e.g. Clip2015-09-25-23232-ENC.mov - this step assumes that there may be other non-actionable files in the folder. Skip if not so.
Set up a batch job that runs periodically, whose first command is to rename all files with the suffix, like by adding a prefix or another suffix. And whose 2nd command is to move all files with the new prefix to folder B
While the encoder is working on a file, it has a lock on it, and so only completed files will get renamed. And only those will be moved to B.
Use any of your aforementioned FTP apps to watch folder B and transfer files.


Can't apply transition effect between clips in Premiere Pro

When you apply a transition between two clips, Premiere needs to use the frames of footage for each clip that go to the start and end of the transition. If there's no footage past that point, it won't allow you to apply the transition.

Consider my illustration below.

You may need to have some footage remaining after the end of your clip to allow for this. Re-import or trim your clips to allow some footage to 'show' underneath the dip to white.


ffmpeg - video conversion with multiple audio tracks

Use

ffmpeg -i "!original!" -map 0:v -map 0:a -c:v libx265 -preset medium -crf 28 -c:a copy "g:\Prepare\Convert\!file!"

FFmpeg by default only picks one video, audio and subtitle track (if they are present) from among the sources. Express map assignments are required in order to include other streams. 0:a selects all audio streams.


Using ffmpeg to convert to Photo Jpeg with minimal loss of quality

DNxHD and JPEG are not the only game in town as far as intermediate codecs are concerned (intermediate codecs being high-quality, visually lossless codecs designed for moving media between steps in a post-production chain). Probably the most-used intermediate codec is Apple's prores 422, which can be encoded cross platform using ffmpeg thus:

ffmpeg -i uncompressed.mov -c:v prores -profile:v 3 -c:a pcm_s16le output.mov

One of the biggest advantages of prores is the support for 10-bit encoding, giving you much better colour fidelity. You can also use the prores 4444 variation to avoid chroma subsampling (reduction of the colour resolution) and alpha channel support.

Failing that you can use motion-JPEG, or even 2 flavours of lossless JPEG (I have no idea what the difference is). Oh and there's JPEG2000 if you really want, though it's not recommended. Substitute your codec of choice here:

ffmpeg -i uncompressed.mov -c:v CODEC -c:a pcm_s16le output.mov

where CODEC is one of:

jpegls - lossless JPEG (?)
ljpeg - another lossless JPEG (?)
mjpeg - motion JPEG
jpeg2000 - JPEG 2000

Since you're on linux I won't suggest Cineform, it's a good intermediate codec on win/mac but I don't think there's a CFHD codec for linux yet, and ffmpeg can only decode it (it's been open-sourced so that will probably change). There are a couple of more obscure ones like Grass Valley, huffyUV, dirac and so on, but if you can't use DNxHD it's unlikely these will be any use to you. Just as an aside, DNxHD is freely available from Avid, is it possible to install the codec on the target machine?


Overlay video with picture with transparent parts

In a nutshell, it's the same as you would do in Photoshop.  Resolve has all of the same blending modes as Photoshop does.  In fact, any blending mode is just one of a limited number of ways its mathematically possible to combine one image layer with another.
The main difference between compositing images in Photoshop and Resolve is that in the latter, movement presents additional challenges.  So more accurately, yes Resolve is like Photoshopping an image, but it's like doing it 24 to 60 times every second.
The easiest way to accomplish this depends on your footage.  In the above image, yes, you could cut out the TV screen and plop something into the hole.  But it would probably look bad if that was all you did, and the same is true for Photoshop.  To get a good result in Resolve, think of how you would get a good Result in Photoshop.

You would skew the image you're trying to insert to match the
perspective of the Television's frame.

You would feather the edges of the selection to match the camera's
focus.

You would use an additive blending mode, so that it look like the TV
was emitting light, and you would balance the contribution of the
glare on the front of the TV, depending on how bright you wanted it
to appear.

You might add "spill" as if the TV were adding light to the room
(maybe not in this case, because the room is bright).

But with a moving image, especially if the camera is moving, you also need to "matchmove" or "cornerpin" the image you're inserting, so that it appears locked to the screen.
For the sake of simplicity, lets say that your camera is still and you don't need to track, matchmove, or cornerpin.  If that's the case, then 99% of what you need to do can be accomplished in the inspector panel of Resolve's Edit Page.  There are alternative methods for both the Fusion and Color pages, but the Edit Page is the most straightforward for simple tasks.  The process would go something like this:

Import both pieces of your footage into the media pool (cmd/ctrl-I)

Drag the background image (livingroom scene) onto V1 on your
timeline.  Drag the foreground image onto V2.  Think of the vertical
stack of timeline layers in Resolve like Photoshop's layers.  Like
Photoshop, Resolve "sees" the stack from the top down.

Adjust the size, position, and perspective of the foreground layer to
match the perspective of the TV frame.  In Resolve, select the
foreground "V2" clip, open the inspector panel, and adjust the zoom,
position, rotation, pan, and tilt attributes until your image lines
up.  You can also crop the image a tiny amount, and use the "soft"
slider in lieu of Photoshop's "feathering" controls.

Adjust the composite blend mode in the inspector.  "Add" or "Screen"
are usually good for this type of additive, emissive light.  Adjust
the "opacity" slider to taste.

You can also add effects, similar to Photoshop plugins, by dragging
one from the "effect" tab onto either clip in the timeline.  You
could, for example add a slight glow to V2's clip to help sell the composite.
Controls for these effects will appear in a new tab of the inspector
once you've applied one (the specifics of this tab's placement depend
on which version of Resolve you're using.)


How to make a video from a still image and an audio file?

To expand upon ObscureRobot's answer, use ffmpeg like so:

ffmpeg -loop 1 -f image2 -r 2 -i input1.png -i input2.aiff -c:v libx264 -c:a copy -shortest output.mp4

-loop 1 -f image2 -r 2 -i input1.png tells ffmpeg to loop input1.png forever, at a frame rate of 2fps. -c:v libx264 tells it to use x264 to encode the video, and -c:a copy tells it to simply copy the audio, without encoding. -shortest makes ffmpeg stop when the shortest input ends - input2.aiff in this case.


Which sensor is better for video, cropped or full frame?

It depends.

All of the questions at http://photo.stackexchange.com regarding the relationship between sensor size and Depth of Field (DoF) apply to video as well. (See, for example: https://photo.stackexchange.com/q/12098/15871, https://photo.stackexchange.com/questions/7904/how-does-background-blur-bokeh-relate-to-sensor-size, and especially https://photo.stackexchange.com/questions/3986/when-do-the-differences-between-aps-c-and-full-frame-sensors-matter-and-why)   If you want very shallow depth of field a FF will give you shallower DoF for the same subject distance, field of view (FoV), and aperture than a  cropped sensor will. This is because the FF camera must use a longer focal length than the crop sensor to achieve the same FoV from the same subject distance. If you want very large depth of field the cropped sensor will have the advantage over the FF camera with the same distance/FoV/aperture.

I think what the comment you heard might have been addressing was the difference in resolution that once existed between most cropped sensor cameras and most full frame cameras. Just a few years ago most APS-C cameras ranged from about 10-12MP while FF cameras where at around 18-20MP. This is not so much the case any more as improvements in sensor technology have allowed APS-C cameras in the 18-20MP range. Since 1920X1080 HD video is only about 2MP per frame, any camera in the 10MP+ range is going to downsize the output of the sensor to 1920X1080 so there is not much difference between a 12MP APS-C camera and a 20MP full frame camera in that regard.


Can I run davinci resolve without openCL capable GPU?

I don’t think there’s a way round it. Premiere can operate using CPU only.


Since the speakers are un-powered you will certainly need either an amplifier or a receiver that can handle the Toslink.  Honestly, if you are trying to keep the cost as low as possible, you may have more luck buying new speakers that take digital input.

Toslink input on a receiver is a mid-range feature if not a high end one, so you probably aren't going to find a lot of cheap amps with it and depending on how good the speakers are, it might not cost that much to replace them with a purpose built system. (For example, Behringer makes this set.)

Alternately, you could go with a simple analog amp.  Toslink itself is more consumer targeted and probably isn't going to give you that huge of an advantage over an analog output unless the DAC in the MacPro is really poor, though even if it is, when you are working on a budget, you probably aren't going to get a substantially better DAC, so investing instead in a basic clean analog amp might get better overall results.


phone vs dslr vs webcam for making videos

videos for youtube

This does not describe your projects. Youtube is a place to publish your videos, does not tell the content of them.

but definitely could be better

What could be better? This is the point. You need to know what do you want to imporve.
Are your videos about gaming, where you are on a little corner on a green screen?
Are your videos about you talking to the camera on your room? Do you need to use the bathroom because it is the only place you have? Or you do outdoor videos. Do you really need to actually improve the image quality?

Let me narrow this a bit. Let me asume you are on a bedroom infront of a fixed setup, your computer and your camera. Here is a list of what would I check before getting a new camera.

Light.

Not only the ammount of it, but how does it look. Find a video where you like the light. Is it rim light or a big diffuse light? Is it lateral or on top of the subject?

Background.

Leave a good space behind you. You do not want a mug shot. Put context on it, remove yourself from the shoot and see it as the main subject, and see if you like it.

Sound.

Good sound is probably more important than excelent video quality.

If you still need better video, and you already tested your current phone. (Yes one first section on this answer is, test your phone, and find out if it is better for you) what you want to have on a new camera is

Looks

Flexibility. Duration of the shoot without heating, focus options (manual or good auto focus) conection, etc.

And I leave the looks to the last. A mirrorless or dslr camera have its limitations but have specific lenses that will actually make the image look good. The main things to consider are focal length and aperture.

A focal length of 35mm or more on a cropped sensor.
A wide aperture, a typical recommendation is 1.8 but needs a fixed distance or a superb auto focus system.

All this answer is not to tell you what you need, it is what you need to investigate to find out what you really need.


Does the Sampling Rate affect the syncing process to a video source?

You can tell which one gets out of synch like this:

Set up your camera and your phone like you usually do. Put a clock that shows seconds right in front of the camera. Then, even though this sounds boring, record yourself counting off the seconds.

Synchronize the video and audio in Premiere Pro like you usually do. When they get out of synch, check whether the video lost a second, or whether the audio lost a second. You should be able to tell based on the repetitive rhythm.

Then, as @AJHenderson pointed out, you should replace the piece of equipment that failed. I agree that a camera that can accept external audio input is probably the best option, though it's expensive.


If you run ffmpeg -layouts, you will see that stereo indicates the presence of two channels, one assigned as Front Left and the other as Front Right. If you use -ac 2 in your encode, ffmpeg will create a stereo layout output by default. FFmpeg does not display the individual channel assignments in the readout of the file.


420 vs 422 only really matters in terms of color accuracy.  The significant part is 8 bit vs 10 bit.  The reason RAW files give so much recover-ability is that they are typically 12, or in the case of your 1D mark 4, 14 bit files.  Every extra bit doubles the total number of possible values that can be stored.  Some of this goes in to having more detail within the typical 8 bit range, but some of this also goes in to holding additional headroom above white and below black for a typical 8 bit image.

Even better than shooting 10 bit is to try shooting pure RAW video.  You may be able to actually try this with your 1D by using high speed cards and the third party firmware hack Magic Lantern.  I've used it on my 5D Mark iii and the results are outstanding.  It can record full 1080p resolution with each frame being a 14 bit raw file that has full use of RAW image correction tools.

Alternately, you can help increase recover-ability in 8 bit video by keeping your image away from the black and white points by decreasing contrast.  This will result in a more subdued image without color correction after the fact and will result in fewer total colors after expansion, but it will buy you room to deal with blown highlights and shadows since they will still fall within the 8 bit range of values.  This technique is often referred to as recording a "flat" image.


our existing 4:3 song slides (1024x768)

The real resolution of a slide depends on the program and file format they are in. If the slides are in PowerPoint or similar, they have no native resolution, they have a proportion.

If they are JPG files or a video, yes, you are stuck with the resolution.

A projector has indeed a native resolution, if it is a 16:9 of good quality it could be full HD 1920x1080 or simply HD 1280x720px, in some cases 1366x768px.

A JPG of 1024x768 will be resampled but I really doubt this would be an issue. In any case it is better to store the slides as a real slide, and not as a "photo".

Regarding if a projector will "projet bars" depends on the model and on the graphics card of the computer sending the data. Most likely the computer will also send a 16:9 signal, and the bars will be given by the application, not by either the computer or the projector.

But if your computer sends an old SD signal, the projector might squish or squash the image.


How do I create this slide/bouncy effect in After Effects?

Key is creating 2 additional keyframes after the last one (one copy of the last one 5-10 frames ahead and another one in between). The keyframe in between is for shifting the position slightly into the opposite direction. In order to get a non linear animation ease all the keyframes at the end.

Instructions

Create a new composition and a new solid layer with the dimensions of the gauge
Click the solid layer and create a mask (double click the rectangular mask path icon to create new mask with the dimensions of the solid layer)
Open up the mask properties of the solid / gauge layer MM
Go to the end of the composition and add a keyframe by clicking on the stop watch of the mask path property
Go to the first frame of the composition and drag both right mask bezier points to the left (this will automatically insert a new keyframe)
Copy the last keyframe 5-10 frames ahead and another one in between
With the cursor on the keyframe in between, drag both bezier points on the right side of the rectangle slightly to the left
Select the last 3 keyframes
Right Click > Keyframe Assistant > Easy Ease or simply hit F9

Examples

Bounce to the right

Bounce to the left

Project File Download


Even though Apple Motion is used with FCP could I still use it with iMovie?

You can use Motion to create video that you would import into iMovie. That video could be things like lower thirds, titles, or other graphics with a transparent background, where you place it over other video. But Motion templates you create aren't seen or used by iMovie the way they are in Final Cut Pro.


All of these parameters are specific to the x264 encoder which is used to produce H.264 streams.

x264 has long since introduced a preset system whereby different permutations of values of these parameters can be set at once using -preset value in FFmpeg, e.g. ffmpeg -i in.mp4 -c:v ibx264 -preset slow out.mp4

AFAICT, the permutation of parameters shown in your file don't match any preset. However, you can set preset to slow, and then override the individual parameters, e.g.

ffmpeg -i in.mp4 -c:v ibx264 -preset slow -x264opts "me=umh:subme=9:psy_rd=1.00:0.15" out.mp4

For a guide to individual parameters, see https://en.wikibooks.org/wiki/MeGUI/x264_Settings.


Why does iMovie convert a 1.8GB .MTS (AVCHD) file into a 2.2 GB .mov file by reducing resolution?

Video is practically never stored uncompressed because the data rates are insane if they were.  Each image in a video is 1920 by 1080 pixels and takes 3 bytes per pixel (one each for red, green and blue).  That's 6.2 megabytes per frame.  There are 24 frames in a second, that's roughly 150 megabytes per second for 24p video.  That's 9 gigabytes per minute.

To reduce this size, codec's (encoders/decoders) are used that can compress the data either losslessly(similar to a zip file, they uncompress to produce identical input to the raw, uncompressed data) but typically can take as little as 1/3 of the space, or lossy, where the video is altered to make it easier to compress without significantly distorting the video.  Most HD video is shot with a minimally lossy codec due to the size (H.264).  AVCHD also records using H.264.

If you are outputting to uncompressed or lossless compression for the MOV, then the file size would increase significantly from the compressed AVCHD file, even if the number of pixels being stored has been reduced some.  If you change to a similar H.264 data rate for the mov file, then you should not see an increase in file size.


What is the current status of rolling-shutter-free CMOS sensors on the market?

OK, answering my own question. Sony recently announced a 4K CMOS sensor with an electronic global shutter, see this blog post and the references inside.

So, the status seems to be: reaching the higher end of the market right now (Nov. 2012), the technology does exist. We still have to wait a few years before seeing these global shutters in lower tiers though.


Is there a player that allows copying currently shown susbtitles to the clipboard?

You can select and copy subtitles on youtube. If you have your subs in a common format, you can upload them to youtube with the video and your subtitles will be applied according to the internal timecode in the subtitles-file. Then, when playing back the video, you can select and copy the subs.


Adobe Premiere Pro CC editing/playback performance

There are a couple factors which can be giving you lagy playback.You don't specify your bit rate or codec. If you are editing a processor intensive codec like h.264 (not a good idea) -the processor could start to be a bottleneck. If you are editing a less compressed format like ProRes your drive or RAM can start to become the bottleneck. Since that is the most likely, I'll address that:

Because you have only one hard drive; Premiere is running off it, the OS is using it, preview files are trying to run off it at the same time. Easiest thing to try first is adding a hard drive or two. Ideally: Drive#1: OS/PPro, Drive#2: Project/Source Footage, Drive#3: Previews/Final Exports. If need be: put your Project and Source footage on an external drive and put your Previews on the local (fastest) drive. Once your previews are created, the project won't need to access the project and source very much. Use an "uncompressed" codec like ProRes or DNxHD for editing -a good SSD should be able to handle several streams at a time.

16Gb may be enough RAM, but it's not a given. It depends on the number of streams, bit-rate, size, length of the timeline, etc..


Yellow and white generally mean video (yellow) and mono audio or left channel audio (white).  It is fairly typical for a usb like port to be used as a video connector when the proper cable is inserted.  It sometimes even uses the same exact port.

Note that it requires special hardware in the camera.  You can't simply plug it into any USB port and expect it to work.  RCA's carry an analog signal while USB is digital.  There is however a system called MHL that is often present in smartphones that allows output of an HDMI signal over the USB port, though external power is often required.


Use

ffmpeg -copyts -skip_frame nokey -i {0} -vsync 0 -r 1000 -f image2 -frame_pts 1 keyframe-%09d.jpeg

This will print the pts as milliseconds in the filename.


How to fix Sony Vegas 12.0 blank screen render?

Use VLC to get the actual frame size. You can go to Tools/media information and from there navigate through the tabs to see what the frame size is.

Then enter that information manually into vegas. When you drop your clips in everything should be good to go.

If you are still getting blank frames in the rendered video then I would guess that to be a render setting. You may want to render to a default setting to see if that helps.


FFmpeg does not preserve colors after resizing

Ad 1:

Try adding the -pix_fmt yuv420p10le option (e.g. before -vf). Or only -pix_fmt + for using the same pixel format as the input video has.

If it doesn't help, you obviously have an inappropriate, albeit more common FFmpeg version — only for 8-bit colors. (Your original video uses 10-bit colors, and FFmpeg will try use the best 8-bit pixel format in this case — with the colors' degradation, of course.)

FFmpeg may be built for 8-bit colors or for 10-bit colors, or — in recent time —  for both of them (for your HEVC encoded video).

So you need to build (or obtain by other way) version for 8-/10- or 10-bit color depth.

Ad 2:

Bitrate of 1700 is very low — only 1700 bits per second, i. e. about 212 bytes per second.

To reach such a low bitrate and at the same time reach your 23.98 frames per second, the encoder is limited with  average size for 1 frame about 212 / 24 = 9 bytes only!

Did you see a picture of such small memory? It has almost no information, so the gray image.

You probably wanted 1700k (Kilobits per second) — or, more probably — 170k:

-b:v 170k

so correct your command in this way.

Addendum to Ad 1:

You use the (default) 4:2:0 chroma subsampling (with inevitable color and contrast degradation).
Try the maximum quality, i.e. 4:4:4 (no subsampling), or — if it will be sufficient for you — 4:2:2.

To reach this, use -pix_fmt yuv444p10le and change the video profile to main444-10 (with option -profile:v main444-10).


How can I prevent YouTube from distorting the audio in my QuickTime video?

The problem was that different clips had different frame rates. My phone records a variable frame rate around 30 fps, the Zoom video had a fixed frame rate of 25 fps, the FB live video was variable around 30 fps and the Acapella-via-FB video was fixed 30 fps. I fixed the problem by reencoding all clips to a fixed frame rate of 30 fps with ffmpeg -r 30. (I also set a minimum audio bitrate of 96 kb/s, the bitrate of most of the original footage, with -b:v 96k. ffmpeg defaulted to an audio bitrate of 69 kb/s.)
The QuickTime player refused to concatenate the frame-rate-adjusted clips, so I concatenated the clips in batches of 32 with ffmpeg's concat filter and then concatenated the result of that with ffmpeg's more efficient concat demuxer. (Concatenating in one pass with ffmpeg's concat demuxer dropped the audio entirely from some scenes; I didn't take the time to figure out why.) I was able to combine frame rate adjustment and batch concatenation into one ffmpeg command, i.e. one reencoding step.


GoPro footage: premiere playback performance versus system media player

I have discovered that this problem is specific to GoPro cameras from the Hero3 and range and later.

For Premiere CS6, the problem can be solved by updating to version 6.0.5. The update can be downloaded here. After installing this update I get flawless playback in Premiere and others have reported that this solution worked for them too.


In cartoons, what is created first - video or sounds?

It depends on the exact studio's process, but generally either an animatic (basically a roughly animated storyboard) or the audio is done first.  In the case of Family Guy and American Dad specifically, it sounds like they work on the audio and the animatic first.  The advantage to doing an animatic first is it can help the voice actors visualize what will be happening, but that makes the process take a bit longer (which is particularly bad for TV).

Once the final audio is done, the final animation can be done to match the sound.  It's actually fairly easy just looking at the wave file of an audio track to pick out where the syllables are, though there is also software that can be used to automatically identify the proper moments for different types of mouth movements with pretty decent accuracy.  Once you know all the key frames (the particular points in time that need to have a given mouth shape) it's pretty easy to animate in between them to get the proper facial movement.

While I was researching American Dad's particular process for this question, I also stumbled across this video from the Wall Street Journal that I thought might be of interest relating to the question.


Very easy to do, well theoretically.  On cut actor freezes his body, friends places the prop - in this instance the cat, on action the actor continues his movement.  The quicker and non intrusive the introduction of the prop, the less movement the actor will have and the more seamless the cut will look.

The main thing to remember here is to be prepared to have a lot of takes.. it will take time to get it right.


How to create “page turn / curl” effect in FFmpeg?

You'll need (to compile) a ffmpeg build with a custom filter: https://github.com/transitive-bullshit/ffmpeg-gl-transition, or use node.js script here: https://github.com/transitive-bullshit/ffmpeg-concat

The transition is at https://gl-transitions.com/editor/InvertedPageCurl


How to display a video on different wall sections only?

With even the most simple projector, if part of the image is black, then nothing will be projected at that point, so why not set up your image to be:

  |(canvas1)| blank space |(canvas2)| blank space |(canvas3)|

Deciding whether that space should be black, white or some other colour is down to you - do you want your real flowers lit? If so, make it a white space


Is it possible that the actual video resolution of the t2i/550d is not 1920x1080

The sensor in your camera has about 18 megapixels, and all those MP are used to record pictures and movies. What's different is how the sensor data was processed on the picture and the movie.

Scaling

For the picture you scaled down the original 18MP picture using Photoshop, GIMP or similar. This was probably a high quality scaling operation, so the resulting 2MP image still looks pretty good, since it was generated from the whole 18MP of data.

For the movie, it is the camera that did the scale down operation. The camera has to scale down images at a rate of 24 per second, so it can't use as good scaling as you get from an image editing app. I'm not sure what the algorithm is, but I'm certain its main goal is performance and not quality.

Compression

For the image you took a raw or a lightly compressed jpeg (not sure which one you used). If you went with the jpeg, it's got 4.7MB worth of data. The raw is way more than that.

For the movie the camera compressed all the frames using H.264 encoding and you took a random frame from the middle of the movie. Your movie has 58 frames and is 20.3MB big, so on average, there are just 360KB for each frame if we consider the audio and metadata in the noise. H.264 makes an amazingly efficient use of the limited bitrate by encoding differences between frames, so it isn't as bad as it looks.

So based on the above reasons, I think the picture vs. movie quality cannot be expected to match.


Software used to create such animations?

You could recreate most of the stuff in that video inside Adobe After Effects, if you have all the assets on individual pictures (layers), and not merged on top of each other.

You can easily take a layer (image file) and independently change the position, rotation, opacity, size, etc. with keyframes. If you have the body parts of a character as different files, you can position them how you'd like them by dragging and dropping, and then parenting them to one specific layer, for example, the chest. Then when you change the position of the chest, the entire body moves with it.

It would also be a good idea to have the transparent versions of the flat icons, so you can add a custom background, and no whitespace overlaps with other layers.

It would be a better idea to draw any characters inside AE with the shape tools so you can modify the shape of any of the body parts.


Looking for an accurate Playback FPS from a video

Personally, I use fraps. The only reason I use fraps is because I used to record desktop footage a ton. However, if you get the free version of fraps, it should allow you to see the framerate of the video playing back while the program is open.


Understanding / troubleshooting After Effects crash

It sounds like AE is encountering a point in one of your source files where there may be corrupted data, and while the file might be playable within the AE/PPro canvas, exporting isnt possible because of the way AE reads the file.

I don't see why using Media Encoder would be any different, they are built around the same engine.

I would suggest trying to replace the file you think is the issue with a proxy (same resolution) rendered using another application, perhaps VLC. Another option, would be (you mentioned 6:51 timestamp), is to split your clip in Premiere on a Sequence. Splice 10 seconds before that timestamp, and 10 seconds after. Render 2 separate files out, and drop them in.

This will leave a black hole, which you would have to fill... But that would tell you if the source file is the issue.

Lastly, clear cache, and also you could try accessing the hidden secrete menu in Preferences. On windows, hold Shift and while holding, click Edit - Preferences. There will then be a new "Secret" tab that allows flushing of memory every X frames during output, and some other options.

My guess, bad source. Have to work around it by either re-encoding the file into a format AE likes, or splitting if you can.


Why do we still shoot 23.976 if NTSC and PAL have been replaced?

23.976fps still exists because it's a standard. Cameras became designed to shoot it, non-linear editing software suites were designed to edit them, and devices were designed to play them. Even though NTSC went away, cameras still shot in 23.976fps. Even if they could shoot a flat 24fps, it causes issues in the edit room.
Putting 24fps footage on a 23.976fps timeline will have some issues but can be mitigated by being slightly slowed down or with pulldown. However, you will run into issues with multi-camera setups and syncing audio, hence this
discussion about editors complaining about audio sync drifting.
In the end, 23.976fps still a standard because if cameras switched to 24fps, it would cause issues in the edit room, and if editors used 24fps timelines, it would give pretty much everybody after them in the pipeline a hard time. Even if everybody could adapt to 24fps, most delivery standards are designed for 24fps anyways, so it'd have to be converted back to 23.976fps at some point in the pipeline, therefore it'd make it much less of a hassle to just shoot at 23.976fps anyways.


Which tools are most likely used to create animated video (i.e. corporate commercials)?

I can't be really sure, but most of that can be done using After Effects and a simple screen recording. You record the screen of a phone, put that into after effects, get a picture of a hand and put that into after effects, and just move it around with the frames.

The whole of screen recording could also be made using Adobe Flash or After Effects instead of actually taking it, but it would take a while... This way you could create a minimal and simple version of your app or something, which might be more eye-pleasing and less complicated to the audience.


Remove -vf scale=800:-1 to avoid rescaling. Remove -r 20 to avoid changing frame rate. You're transcoding from a stream in a MP4 to the GIF codec, so the bitrate will not remain the same, nor is there any sense in trying to keep it the same.
A stream is scaled by using the scale filter in a simple filterchain -vf or a complex filterchain -filter_complex or using the -s WIDTHxHEIGHT output option.


How to get audience audio in a small conference/training for 40-80 people?

Here's a video that covers everything you need to know about sound recording for video: http://nofilmschool.com/2015/08/24-sound-basics-will-help-you-lay-sturdy-foundation

If you don't have 18 minutes to spend, the specific answer to your question is that basically you cannot capture well the human voice when a mic is more than 3 feet away.  Even if you use a high-quality mic and a high-quality pre-amp, the quality of your audio will drop precipitously as you break the 3-foot rule.  (There are exceptions such as professional singers and actors hitting PZM stage mics, but even that is not great.)

If you place mics around the room in such a way that nobody has to throw their voice more than 3 feet to reach a microphone, then you might have a solution.  But that might require 20-40 microphones, and an audio system capable of recording 20-40 inputs simultaneously.  Impractical.

Alternatively, you could have 3 mics, one for each zone of 15-30 people, which you can rapidly run to whichever audience member is trying to speak.  When they hold the mic (at least 1-2" from their mouth and at most 3 feet away), you should get fairly good results.  That would require an audio system that can record four tracks simultaneously (one for the podium mic and 3 for the audience mics), which is very simple nowadays.


How to add freeze frame to a video using ffmpeg

Assume there are three pauses of 3 seconds each at 5s, 12s and 20s of the original video. Here's the basic form of the command,

ffmpeg -i in -vf "setpts='PTS-STARTPTS + gte(T,5)*(3/TB) + gte(T,12)*(3/TB) + gte(T,20)*(3/TB)'" -af "asetpts='PTS-STARTPTS + gte(T,5)*(3/TB) + gte(T,12)*(3/TB) + gte(T,20)*(3/TB)',aresample=async=1:first_pts=0" -vsync cfr out


poor quality export of still images from premiere

That looks more like a 'field' from the video, rather than a frame -- jagged diagonals are the tell.

If your video is interlaced, you may only get half the vertical resolution in a still, unless you specifically set it to output a full frame. Check the export settings.


There is a rule for something like this, however, it has nothing to do with image resolution.  To calculate the area of a scene a camera will cover, you need to know a few things:  A) Distance to subject.  This one's easy.  B) the focal length of the lens, and C) the sensor size, also sometimes called "film back" or "gate".  If your image width to height ratio is the same as your sensor's you probably won't need to know D) aspect ratio, but for some cameras you will, so I'll include it for good measure.

From there, you should be able to use any number of online FOV calculators to tell you the area of your image.  Here is a link to one I found with a Google search.  The website also explains most of this better than I can and includes the mathematical formulae.

If you've ever used a magnifying glass to focus light onto a point, you're probably aware that the shape of the light it creates is circular.  The same phenomenon happens inside a camera.  Your camera's sensor sits inside of this circle.  Now, if you imagine your sensor divided into many tiny pixels, you should get an appreciation for why resolution does not affect this equation.  It doesn't matter how finely you chop up the rectangle -- whether it's 3840, 1920, 960, or eight pixels wide -- the sensor doesn't grow or shrink.  It always fits within the image circle.


Keyframes
Most video editors have some kind of keyframes feature. By using keyframes, you can change the values of the position and scale of the video for a single frame and have different values for another frame. The video editor will then calculate what the values should be for all the frames between these two keyframes so that these change gradually over time. This way you can make subtle and continuous changes to the framing of your video and you could use this to make your subject stay in the center of the frame without it being too distracting.

Tracking
In the case that manually setting all the values is too much work, professional video editing software often have some kind of tracking tool which can track the subject for you. You can then let the position of the video follow the path of the subject. But for just keeping the subject in the center, tracking would most likely be too much of a hassle.

So what kind of software could do this?
This would be possible to do in most modern professional video editors. But for example, you could do this in Premiere Pro. Make sure to check the documentation and help forums of the software for the specifics on how to do this and I also suggest looking up a tutorial. Also bare in mind that cropping part of the video will result in a loss of quality since there will be less pixels to be displayed, no matter what software you use.


Analog to digital converter and then FW in to mac from there.


I have a .ts video containing a 720° video record it with an AllieCam360

FFmpeg can see both views as separate video streams.

You can remux the file to MP4 simply by using

ffmpeg -i input.ts -c copy -map 0 output.mp4

Hopefully, your video editor can work with distinct streams, else they will need to be combined in some way.


What equipment do I needed for filming dance instruction?

To answer your questions:

1) A DSLR is fine for a first try out. As an acquisition format (not delivery), HD is on its way out very fast though. The rage these days in 2K or actually 4K. So, later or now, look into, getting a camera that does that. For a DSLR price-range and for a person who is not used to shooting video, I'd recommend the GH5 that just came out.

2) If you use a DSLR-like camera, use an external recorder, and sync the audio and the video later, in your editing program. This will give you more flexibility and better quality, for sure.

3) Look for cameras that work well in low-light conditions. DSLRs work rather well generally. And yes, if you are moving a lot, stay away from cumbersome equipment: you'll be exhausted before you've shot one image. Have with you a case of 650W lights perhaps, with their stand and a couple of sand bags and extension cables. These are versatile and can enhance your image nicely.

4) As regards the music, best would be to digital-feed it into a recorder and record on-set ambiance as well, on top of miking your talent. So yes, that's a lot. Short of that, I'd mike the talent and record on-set audio. You can add the music later in post and mix the on-set ambiance with it.

5)

Aim to get good footage and very good audio. So, when you visit a
location, look and listen: if it looks good, it might not sound good,
and vice versa.
If, while you're shooting, you start to hear sounds coming from outside the venue, stop the shoot and try to stop the sounds from
happening. Why? 'Cause you want your footage and production audio to
be as good as possible the first time around. It can be very hard to
save bad footage or bad audio later on, in post. So get it right the
first time, while keeping an eye on the clock, the budget, etc.
In post, use filters to clean up your audio tracks, like the iZotope RX programs.
Test your gear before you show up on set. Make sure you know what you're doing with it, so as not to waste your time and your talents'.
Have at least one assistant with you on each shoot, either hired on the spot, or someone who travels with you. You don't want to overextend yourself too much, particularly since you're starting out. You don't want to do everything poorly and later become disillusioned with the process. It's not easy ... but it can be rewarding.


Why would a company put black lines around the picture in their DVD?

Old/small TVs tended to overscan their images.  The "title-safe" area was about 90% of the original image.  The DVD's format ensures that despite such overscanning, everything in the image is visible, including the titling shown in red at the bottom of the image, which is hard up against the limit of the frame and thus requires that the image be reduced so that a 10% overscan does not clip it off.


My two cents...Video quality can be determined by several things (e.g. codec, bitrate, compression, etc.), so just looking at the container (i.e. MOV vs. MP4) isn't a sufficiently in-depth way of finding out the best option.


How compatible are high dynamic range and fast movements?

There is rarely a direct relationship between HDR, or dynamic range in general, and motion artifacts. There may be an indirect relationship when trade offs are made for transmitting or storing the increased dynamic range. A specific implementation might reduce the frame rate or increase the compression in ways that introduce motion artifacts.


Do blanking intervals appear on both sides of a frame or just the top and left?

They are both right, depending on the context and level of detail. The latter accurately describes what happens within the waveform. If you look further down in your reference, it shows that there is a "front porch" and "back porch" of the horizontal and vertical intervals.

However, the former describes what happens practically, especially in terms of the useful parts of the vertical blanking interval (VBI). Closed captioning, teletext, VITS, VITC, AMOL all use the blanked lines at the top of the field to transmit their data. (You should also note that your reference intentionally chose this layout in order to draw parallels with digital VANC and HANC, which are only at the top and left of the picture.)


drawtext ffmpeg 'Unable to parse graph description substring'

For simple filterchains, where one filter operates upon the output of an earlier filter, no input pads (like [0:v]) should be used. Also, there is an errant colon at the end of the pad filter. It should be a comma instead, so
-vf 'pad=ceil(iw/2)*2:ceil(ih/2)*2,drawtext=text="hello":fontsize=90:x=20:y=20:fontcolor=white@0.2'

In drawtext, you may need to specify a font if fontconfig is not available on your system.


ffmpeg - H264 vs. H265 codec parameters?

Some of those options don't belong to x264.

Use

-b:v 62914560 -bufsize 62914560 -maxrate 62914560 -movflags +faststart -x264-params keyint=600:min-keyint=60:scenecut=00


Issues importing iStock comps into After Effects

After Effects works better with codecs that compress each frame individually (intra-frame codecs).  FLV files compress across multiple frames (inter-frame), as do mp4 files.  If you can get your FLV successfully converted to a codec like ProRes, it should work correctly in After Effects.  FLV files are quite unreliable in conversion- there's a post here that might help - it seems most people use the (now deprecated) open source Perian codecs to get this to work:

https://forums.creativecow.net/thread/8/1038982

Your best bet is probably to find source stock material in a format that is easier to work with (most videos on iStock are now mov/mp4 which should be easier to convert)

(NB - I'm not sure this is really an After Effects question.)


How to split video into multiple files based on chapter markers?

mkvmerge, a part of MKVtoolnix, will split a MKV file by chapters.

Basic syntax is

mkvmerge -o chapter.mkv --split chapters:all input.mkv

but see Section 2.5 #7 of the documentation for more details.


Go to File > Project Manager.
Select the problem sequence.
In the "Resulting Project" menu, select "Collect Files and Copy"
In its options, select "Exclude Unused Clips" and unselect everything else.
Pick your destination path (not the drive where your .avi are located).
Press OK and start the copying process.

Once the copy is done, select all these files (they are all avi.) and transcode them to whatever you want, without changing their names. That supposes that you are going to export these transcoded files to a different folder than the one where your newly copied .avi files are located.

Once the transcode is done, put a dash in front of the folder in which you copied the original .avi files.

Boot up your Premiere project. The program will ask you to reconnect the missing media. Direct it towards the folder where you put the transcoded .avi files. Because you didn't change the files' names, you'll have no trouble reconnecting your sequence to the newly converted files. No more .avi.


Does anybody get a strobing effect when filming video with the D90?

You seem to be on the right tracks, fluorescent tubes are notorious for flickering and CMOS sensor is read row-by-row in video mode.

Try shooting under window light and/or use your own lighting, e.g. a LED video light. Try shooting so there's not much office visible in background, you won't be able to light it all.


How to set pts time format when using ffmpeg filter to add timestamp

Do

In order to draw Timestamp: 01:25., you should specify this one to (feed) ffmpeg:

drawtext = text = 'Timestamp\: %{pts\:gmtime\:0\:%M\\\:%S}.'

Don't

If you specify this one to (feed) ffmpeg:

drawtext = text = '%{pts\:gmtime\:0\:%M\\:%S}'

, it gives Unterminated %{} near '{pts:gmtime:0:%M\' error.

But in bash

But if you're using bash-like shell and a weak quote, "......", to feed it,

\\ is escaped to \, and
\: is not escaped but remains without any changes because \: is not an escape sequence.

So it should be:

-filter_complex "drawtext = text = '%{pts\:gmtime\:0\:%M\\\\\:%S}'"

i.e. bash's "\\\\\:" for ffmpeg's \\\: for getting a single character : displayed.

Note that

If you only want to apply one or more filters to one video stream (e.g, drawtext), you can use -vf instead of using --filter_complex. The latter is reserved for applying filters on multiple streams.


Calculate after effects composition un-stretched time

The source time of a layer is found with the expression

thisComp.layer("some layer").sourceTime()

More about it can be found by reading the manual.


On this question @hasanyasin and I provided you with alternatives for slideshow presentations. Additionally I place here a part of my answer, just for your convenience:

  Anyway, what you wish to do in a video can be achieved by a
  professional non linear editing system, like Sony Vegas or Adobe
  Premiere, of which Sony Vegas is the easiest to learn.

  If you are used to Microsoft Based Products (PhotoShop, Corel Draw,
  Office, Movie Maker, etc.) you are almost ready to do it.

  The process to place you in front of the moving images, videos,
  transitions, text and other media is called "Chroma Key" and it can be
  reached in the Effects tab of the Sony Vegas 8 (and previous/further
  versions). A video tutorials on how to create the Chroma Key effect
  can be found on youtube by dropping the terms "chroma key sony vegas",
  here is an example:

  Basically you work in multi layer. Placing in a time line the elements
  in the order that you wish them to appear on screen, adding a
  background, in/out transitions, and other elements. Remember that the
  top layer will be the "front" element on screen. After which you
  insert your blue/green screen video at the very top, apply the Chroma
  Key effect, choose the dropper and select the background in your
  video, after which you adjust the threshold in order not to appear
  like a ghost in the video.

  You will need to use the "Event Pan and Crop" tool in order to create
  the "moving" effect for some static items, like pictures and even if
  you wish your videos to "fly" around the screen. Just run a search in
  youtube with the words "Pan and Crop Sony Vegas" and you will get tons
  of results. Here is an example:

  And yes...  you can create awesome results in a couple of hours. Give
  it a try and drop us back a link with your published video.

Good luck!


Using brush tool for alpha channels/rotoscoping in after-effects

The thing about masks is that you don't have to do them on every frame. To quickly do rotoscoping you let the computer do as much of the work as it can, by interpolating wherever possible.

To mask out the hands with the pen tool, draw the mask for the first frame and then move as far along the timeline as you can until the point where the motion dramatically changes, e.g. if the hand is moving up, continue until it stops or starts moving down. Adjust the mask points, trying to keep the points close to the part of the hand they were near when you first drew them. It's good to give yourself enough points to work with when you first draw the mask.

Now go back between the two keyframes and find the point at which the maksk is the furthest from matching. Re-adjust, thus making a third keyframe. Now
rinse, repeat: between each of your keyframes, pick the point where the mask is the worst and refine.

As you work you'll find that the mask needs less and less tweaking and eventually starts following the hand well. If your motion is really crazy this might not be until you've done every frame, but the adjustments you'll need to make will be smaller and smaller each time.

You'll find this will be tedious, but way less tedious than rendering as an image sequence and photoshoping each frame, or just opening the movie in photoshop (which is the answer to your question BTW). The difficulty in getting smooth motion that way would be immense. Think about the way hand drawn animation looks - the lines constantly 'boil' because each frame is painted from scratch. Painting the matte frame by frame will give you a result like that, which might be nice, but it doesn't seem like the look you're going for.

Put on a podcast or some music, make a coffee, get comfortable and get busy with the béziers.


Can Davinci Resolve convert a movie into (png) pictures...?

From the Blackmagic Forum "You can only export TIFF files (which then can be converted to png's with an external tool), not PNG's directly. "


Edit lists is a feature, that allows you to edit videos without re-encoding. For example, you want to remove a scene, make your edit points which are written into the container file. A video player reads those instructions and just such parts of the video. However, not many players seem to support that feature, nor does Instagram, so simply don't use it. I think it's not possible with mp4 only with mov anyway, so nothing to worry about.
The moov atom contains information how to play the video (duration, fps, etc.), it needs to be at the beginning in this case, which allows to start playing the video over the internet immediately while more data is loaded. In contrast, when the moov atom is at the file's end you need to wait until the video has been fully downloaded/buffered. The moov atom is rarely an issue in practice, most editors don't even allow to configure it and just put it at the front of the video file after the encoding is done. With ffmpeg you have control by using certain flags (I think -movflags faststart).
Progressive scan is the usual way to present a video on progressive screens (which means any screen in any modern device). There is also interlaced which is still somewhat relevant as a legacy format for TV but should always be avoided in the web. The difference is that progressive scan works with a full image per frame whereas for interlaced scan two half fields are combined into one image. Interlacing worked well on old CRT monitors, but not on modern devices. Both of these variants are often marked with a little suffix after the resolution of a video. For example you will see 1080p, referring to a video with a resolution of 1920x1080 using progressive scan, or when you see 1080i it means again a resolution of 1920x1080 but using interlacing. When creating video projects or creating a sequence where you put clips together or before export you may be asked to select profiles. Just make sure you always pick one of the progressive profiles where resolutions have the little p as suffix. Some tools may omit the distinction if they only support progressive scan.


exporting .mov vr to multiple still frames

Using Quicktime Player 7 you can export any movie file as an Image Sequence

Open your .mov file using Quicktime 7
File > Export
In the Export dropdown select Movie to Image Sequence

Open the options and set the export format (eg JPEG or PNG)

If you want just the current frame leave the frames per second blank. Otherwise, enter hte videos frame rate and you will export ALL the frames.


MKV/MP4 container support chapters too, it also supports h264 and almost any other codec. MP4 container based on MOV container, so you can try to include h264 in MOV too.


what is preventing me from streaming video correctly with nginx?

tunist:

You've gotten pretty close to getting this going - nice that you did the curl to determine that the byte-range was not being honored.  I had done exactly that in the past when setting this up.

If you check here: http://nginx.org/en/docs/http/ngx_http_mp4_module.html  You may find what you're looking for - it is unclear whether you're using this module or not already, so perhaps this is what you need.

--dan


After Effects Radio Waves FX Initial Size

Generate radio waves on a solid, adjust settings so they're looking appropriate.

Drag the time cursor forward until the waves have expanded to the point where you want them to start.

Cut your layer using the alt + left square bracket ( alt + [ )
Drag your layer left until it is at the beginning of your comp.

Make a solid layer that goes between your radio waves layer and your mouse image.
Mask the solid to the same size as your mouse image.
Set the Track Matte on your radio waves layer to "Alpha Inverted"


Which tool or method should be used to make text on a whiteboard look natural / right?

Your use of pitch and yaw is correct, but it looks like you have just overcompensated a little. Your vanishing point for the lines is too near - that bottom line shows this by angling up too much.
If you correct them by assuming the vanishing point from the top and bottom of whiteboard, you will get a more natural look, and then your text will look more natural.


Both Speedgrade and Davinci Resolve have scene change detection.

Davinci Resolve is also free. I am not sure however on how exactly it detects scenes changes.


Halve framerate without complete re-encoding

I think the term for this effort is statistical multiplexing where your proposed framework would be an efficient implementation thereof.


How do you edit in multicamera mode if you have a mask on one track?

Here's what I ended up doing.  I created a mask the way you would normally create a mask, and the end result was that I had 2 video tracks.  Any tutorial on the Internet can show you how to do that.

When I got ready to create my multitrack edit, I included every video track except the 2nd video track mentioned above.

In other words, let's say I have 3 video tracks; V1, V2 and V3.  V2 is the camera angle where the person's face can be clearly seen, so I put a pixelated mask on the person's face for the whole clip.

When I make my multicamera track I only highlight V1, V2 and V3,  This combines those 3 into one track, and V4 remains it's own separate track.

Now when you make the cuts and edits, that pixelation mask will still be on any shot where you use V2 as the source, but will not be on any shot where V1 or V3 is the source.

Just remember, when you render the video make sure the mask track, the one you didn't add to the multicamera track, is above the multicamera track in your track layout so it lays on top of that track instead of under it.


Are there any good video editing apps for photographers?

I don't have any personal experience with video, but Neil van Niekirk, a photographer whose articles have thrown lots of light into my understanding of event photography, is using iMovie. Even though he wished for something more powerful 8 months ago, it seems to have remained his tool of choice so far. Armin Defiesta, formerly videographer, now mostly photographer, has written a comparison of iMovie vs Final Cut Pro X.

I suspect part of the learning pain comes from the fact that video processing tools are based on heritage of movie film processing, not evolved from photography tools. The terminology and primary controls therefore have been evolving independently.

About EXIF info - are you sure your clips contain anything relevant in the first place? Most video file formats don't have any support for that. See what metainfo your camera can show you about a recorded clip.


Wedding Footage from beach - fixing over-exposure and colour balance?

What you are trying to do is impossible given how bad the original footage is.  I'm honestly pretty amazed at the result in the third shot given the original state.  Unfortunately, video frames are the equivalent of a series of JPEG images.  It is possible to shoot RAW video on ultra high end cameras, but the data rates are completely off the charts (around 90 to 100MB per second or worse).  The information is simply gone and there is no way to recover it if it was clipped out.

It sucks, but that's the long and short of it.  That's why I always do a pre-roll test prior to filming at weddings, but that's what experience of doing professional wedding videography for 3 to 4 years gets you.


Is reencoding a YUV 4:2:0 video in a 4:2:0 colour space lossless?

Probably no loss, but there is more to it than just YUV420. You can need to make sure the same ITU-R Recommendation is used (BT.601, BT.708 or maybe even 2020) In addition make sure the same color ranges is used (0-255 vs 16-235)


It's not the best variant, but in my case it helped. I getting data with ffmpeg then routing output to vlc2 via pipe and transmitting it to rtp with the following command:

  ffmpeg -re -i HLSstream -c copy -f mpegts - 2>/dev/null | vlc -
  --ttl=255 -I dummy --sout '#rtp{access=rtp,mux=ts,dst=IP,port=PORT}' :sout-all :sout-keep


Is there a way to split a mp4 into 2 mp4, one is metadata.mp4 and another is mediadata.mp4

If I understand you correctly, you want the MOOV atom to be stored at the end of the MP4 (after the media payload). If so, this is the typical scheme used by ffmpeg unless flagged otherwise. So, copy your current MP4 into a new container via ffmpeg:

ffmpeg -i input.mp4 -c copy output.mp4


How to convert a 2:21:1 video to 16:9 DVD using ffmpeg?

Having seen the sample, this is the command

ffmpeg -i in.avi -vf pad=720:576:0:144,setdar=4/3 -target pal-dvd out.mpg

The video is square-pixel, so scaling is not required. The frame should be treated as 4:3, not 16:9 (which isn't the right ratio for this movie anyway).

For widescreen playback in the PAL standard, your rendered raster has to be 1024x576. So,

ffmpeg -i in.avi -vf scale=1024:288,pad=1024:576:0:144 -target pal-dvd out.mpg

scale=1024:288 --> the video is scaled to the final display width.

pad=1024:576:0:144 --> vertical pixels are added to make it to 1024x576.

-target pal-dvd --> this will rescale the video to 720x576 and set a DAR of 16:9.


Youtube 360 videos are in EAC, equi-angular cubemap format. FFmpeg have filter named v360 that can convert such videos to equirectangular or stereographic (also known as tiny planet) format (among many others) by using CPU.


Script to create video in standard format?

I'm not aware of any software that does what you are looking for.  The workflow doesn't really fit within a typical post-production workflow, so there isn't really a reason for it.  You can find software that will do things like adding the beginning and ending leads to a video based on meta data, so doing the titles automatically should be possible.  However, actually making automated edits based on timestamps is fairly non-typical.

Generally, the clips are cut in as they are reviewed if you are reviewing that way.  You can watch a clip, set an in and out point and then send it to the timeline.  This way you document the edits and build the sequence at the same time.

Your best bet would probably be to use software for making EDLs (editing decision lists).  If you can produce an EDL with the cuts you have defined in your "script" then software that can process EDLs (such as Premiere) should be able to make use of them.  Normally EDLs are used for transitioning between different editing systems, so it should be possible to modify or create your own EDL fairly easily.


How to render png's as h.265 12 bit video?

Use

ffmpeg -framerate 500/21 -i %d.png -i audio.wav -c:v libx265 -x265-params lossless=1 -pix_fmt yuv422p12le -c:a copy output.mkv

You'll need a ffmpg with a libx265 that supports a bit depth of 12. At this time, I can't find such a precompiled binary so you'll have to compile ffmpeg using the auto-build script at https://github.com/jb-alvarado/media-autobuild_suite


How do I prevent Wirecast from crashing?

If you have an external monitor, try unplugging it and loading up Wirecast.  Some people have reported too much video resources being in use cause problems.


How to burn HD videos with menu system onto DVD media?

Sorry to say this, but DVD does and will not support HD videos - at least not with menu and other DVD features. HD-DVD didn't survive on the market - Blu-Ray did. The problem is that the amount of data necessary to create a HD image is higher that the bit-rate of DVD-Format.

You can save various file formats on a DVD-ROM and some DVD players can play those formats. But "native" HD on a DVD is not supported. Some DVD Player can upscale certain compressed formats, but that will not show real HD.

See: http://www.dvddemystified.com/dvdfaq.html#2.3.2


miniDV - Same resolution but lost vertical space in 16:9 widescreen?

Okay, after some reasoning and research I think I understand what happens.

Basically, the sensor is fixed in size, but the lens is too. Which means the only way to get a wider sample to fit the image to 16:9 is to crop down the image on the sensor to about 720x405 pixels, each pixel catching a sample of ratio 64:45 (SAR).

The image is then stretched vertically to fit the whole 576 lines of the PAL standard. This means the original 5:4 footage captures has the same horizontal FOV as the footage captured in 4:3 mode, but a lower one vertically, stretched up to fit the whole 576 lines. This allows for the recorded media to then be stretched back into 16:9 by the media player.

This last step (the vertical stretching done by the camcorder) is still something that sounds really puzzling to me, but after analyzing some more footage, it is rather obvious that it is a digital upscaling and not an analog capture of the samples, since a lot of the digital noise is stretched vertically too.

It is an interesting way to get around the hardware limitations of the camcorder, but in the end not really worth it, considering the loss in quality.


Is there a way to link the animation of two layers?


Upper half shows one video track, lower half shows another

The easiest way is to use nested timelines.  Make each source timeline the appropriate size for the half it is on.  Apply the motion within the nested timelines.  Then place the nested timelines on the top and bottom of your final timeline.

I use this technique regularly in both Premiere and After Effects when I need to combine multiple elements into a layer than I then want to manipulate as a whole.  In After Effects, adjustment layers are also an option, but I often need to treat the same sub-asset in different ways in different finished videos (working on lower thirds generally), so the nesting approach makes more sense for me.


The way this is usually done is either by recording the screen at full resolution and zooming out the footage until you want a close-up, or by using a screen recorder which allows you to zoom in as you're recording.

But if you already have footage, any decent editor should allow you to zoom in. Just know that zoomed-in footage will be at a lower quality than recording at the full resolution and cropping.

If you're on Windows, you can try Adobe Premiere or Sony Vegas. There are probably others, but those 2 are fairly popular.


Expressions can only ever return one result. In your expression the two last lines both return a result, so the last one is what the value will be.

Wiggle is a little bit confusing, in that it is not a function like Math.sin or random, that takes the value to be wiggled as a parameter. It is actually a method of the property, so when you call wiggle() in say, the position property, what you're actually calling is someLayer.transform.position.wiggle(). This returns a 'wiggly' value based on the value of the property, it doesn't actually change the value of the property itself.

So to use the result of the wiggle expression in combination with other values you have to get the result of the wiggle expression, and use that in your final result. There is no need to add value to the wiggle result, because it is already added. Also, there is no point multiplying it by 1, that does nothing.

ctrl = thisComp.layer("diamond_control"); //just for neatness
x = ctrl.effect("Horizontal")("Slider");
y = ctrl.effect("Vertical")("Slider");

wiggle_x = ctrl.effect("wiggle_x_pos")("Slider");
wiggle_y = ctrleffect("wiggle_y_pos")("Slider");

w = [wiggle(wiggle_x/100, wiggle_x/10)[0], wiggle(wiggle_y/100, wiggle_y/10)[1]];

w + [x,y];

I'm not sure why you use the wiggle_x_pos and wiggle_y_pos slider for both the amplitude and frequency parameter of the wiggle. The first two values you give to wiggle are the amount of wiggliness and the frequency of the wiggle. Your expression would increase both frequency and amplitude together, that might be what you want. In the expression above this would then be added to the value given by the horizontal and vertical slider, which would be an offset, so that if x and y are equal to 0 the layer would wiggle around its base position. This seems a bit back-to-front.

If you want a set of controls for the rest position, the amount and the frequency of the wiggle I'd set up the 'diamond_control' layer with two point expression control effects on it and one slider control. The adfvantage of using a point control is that you can control both parameters with a single control, right from the comp window. So given that setup you'd use this:

ctrl = thisComp.layer("diamond_control"); //just for neatness
amplitude = ctrl.effect("Amplitude")("Point");
basePos = ctrl.effect("Base Position")("Point");
freq = ctrl.effect("Freqquency")("Slider");
w = [wiggle(amplitude[0], freq)[0], wiggle(amplitude[1], freq)[1]) - value;

w + basePos;

You can see that on the second line I subtract value from the wiggle result, this means that it just returns the wiggle offset, not the original base position. So that means the base position will be only set by the Base Position effect control.


ffplay won't play internal(embedded) subtitle?

You can use subtitles filter like your example in your question but point to the same input file:

ffplay -vf subtitles=input.mkv input.mkv

If you want to choose a different subtitle stream then use the stream_index option. This example will choose the third subtitle stream:

ffplay -vf subtitles=input.mkv:stream_index=2 input.mkv

Or use mpv player and press j or use --sub=1 option.


Animating vectors to audio in After Effects

I would build one of the "stacks" as a comp.  On the first frame of the comp, I'd have the first layer in the stack, and on each progressive frame I'd add the next layer.
Then in my main comp, I would put the music track, and use something like Sound Keys from Trapcode or generate keyframes from the audio using a technique like this:
https://www.surfacedstudio.com/blog/vfx-vlog/after-effects-audio-to-keyframes/2

Once you have the audio keyframes, then you could use an expression to display a specific frame of your comp based on how loud the sound is on that frame.

once you've got that working, then I would think about applying this to more than one stack, and thinking about how to apply different behaviours to different stacks, either based on different EQ settings or maybe on a time delay, so the audio appears to ripple across the stack.


Adobe encore - Highlight button with image

Sounds like it may be some kind of a processing glitch.  Menus don't actually do an overlay when you mouse over them, they display a different image.  If you export one button with highlight and one without, you can specifically set the hover image of the button to be the one with the highlight.  You specifically have options for selected, unselected and hover.

If you need more detail about how to do this specifically, I can put together some screenshots when I get to my editing workstation, but I seem to recall it being relatively easy to find in the properties of the button.


iMovie Help: Transition still keeps the previous clips' audio

Generally speaking, a transition will start before the end of a clip.  You need enough video to have something to play while the transition is occurring.  The video will normally keep running until the end of the transition and that also means that the audio will keep running until the transition finishes.  You would need to play with the volume adjustments to bring down the level of the track that you don't want to have keep playing.


What to do when camcorder angle does not cover entire area to record?

You're correct that you either need to place the camera farther away until the entire field is in view, or use a wide-angle lens adapter (not necessarily "fisheye" but wider). For indoor soccer, clearly you're limited by the walls.

Presumably, you want to hit "record" and enjoy watching the game, rather than having to actively pan the camera back & forth. Also, I'm presuming you only have 1 camera & 1 operator, and you don't really intend to edit the footage together later... If that's the case, look for a wide-angle adapter & put the camera as far away & as high up as possible (a GoPro or similar as suggested previously might be easier to stick high up on the wall :))

For most basic consumer camcorders, you can get a wide-angle adapter to screw onto the front for about ~$40 (make sure the lens & screw threads are the same size or find one specifically compatible for your camera). That should give you ~20-30% wider field of view. It won't be perfect & might be slightly distorted, but it will capture more of the field than you would otherwise.

That still probably won't be enough to capture the entire game from mid-field, but it will get more of it. To fit the whole thing you'd likely need to be up on the ceiling or on a ladder at the top of the bleachers. Not safe, or easy to maneuver.

If you watch professional soccer matches on TV, you'll notice that they don't capture the entire field either, but instead follow the action of the ball. This is because 1) that's the focal point of the game and 2) In order to really see the whole field the camera would have to be so far away you wouldn't really be able to tell what's going on anymore.

There's little/no zooming (instead they cut between cameras). They tend to keep the player w/the ball just off-center, so there's room for them to run & not go out of frame. Mid-range or close-up shots are usually done w/separate cameras, often at field level along the sidelines. As you'd suggested, you could put a camera near the goal line & see the whole field, but then you're down low & will only capture what happens nearby in that half of the field.


Actively Used and Developed Motion Capture Systems

We used the NaturalPoint OptiTrack S250e at my company for a big project that is still in active use today. We used it for a sort of game like exhibition on fairs. So it had to be quite robust and offer stable tracking in changing environments.

It is primarily used for movies and video games though. They offer quite a few different systems in price ranges far below your 40.000$ and far above that, depending on how many cameras you need and what precision you need. The prices are per camera.
They have a nice system configurator here, which makes choosing camera count and camera system a bit easier.

Some of their bigger customers can be found here. Seems like they have been proven in many bigger productions.

I have not affiliation with NaturalPoint and it's the only MotionTracking system I had contact with. There might be better solutions that I don't know of but we used their products and the result were satisfying for our special requirements.


Can't get audio and video speeds to play at original speeds

Sometimes this will happen from a verity of reasons. Sometimes the clocks are different. A lot of time it comes down to manual re-syncing.
Pick 2 sync points for the Video and the same 2 points for the audio. Make sure they are as far away as possible. Now divide the duration in frames between the 2

V dur / A dur = ratio

Now you have the ratio you should speed up or slow down the sound (sound is more pliable). Good Luck!


Can video cameras perceive lights in a way that they will totally change the color of molten metals?

For starters,

You need to research Infrared light pollution caused by the high temperatures of the materials you're trying to image.  Most cameras have an IR filter on the sensor, which blocks incoming wavelengths which are imperceptible to the human eye.  These filters often have different characteristics depending on the camera make/model/manufacturer, which is why I say you need to do some research in that area.

It's possible to remove these filters, and photographers who are interested in IR photography often do; but because the glass of the lens bends visible light differently than IR light, there's effectively different focal planes for the two, and you can't focus them both at the same time.  So, IR photographers will typically remove the sensor filter, and then attach an IR-pass filter to the front of the lens, which blocks the visible spectrum, and only allows IR light through, allowing the IR image to be properly focused.  These IR pass filters are available in different wavelengths.  IR pass filters won't be particularly relevant to your situation.  However, IR cut filters may be.

When IR photographers remove the IR filter from their sensors, they effectively destroy the camera's ability to take "normal" pictures.  This is one reason IR cut filters exist.  They screw on to the front of a lens, and cut the incoming IR light, allowing a modified camera to behave normally again.  But also (and here is where you might be interested) they supplement the IR-blocking capabilities of normal cameras, which may be suffering from IR pollution for various other reasons.  Pointing a camera at hot metal isn't the typical scenario; more commonly, cheap Neutral Density filters and long exposures introduce IR light that the sensor filter wasn't designed to handle.  However, ensuring that only the spectrum you want to capture is striking your sensor should help in your situation.

Other than that, make sure your white balance is set, because that can also tint the image, and get a good quality color chip chart for reference; most of them are made from plastic and wouldn't stand up to high temperatures, but there are some metal ones.  You'd still need to keep it from melting, and be sure the dyes on the color chips were stable at whatever temperature you needed them to be.

Since you're pointing a camera at something very bright, you should be aware of the phenomenon known as aperture diffraction, which will affect the image's sharpness, but not so much overall color (although the colors of edges might be affected slightly; see halation, fringing, and chromatic aberration).

You might also be interested in a more full-spectrum camera, designed to image light invisible to humans, depending on your budget.  I think Flir might make some, maybe?  They're more commonly used in manufacturing and agriculture.


How much recording time at 1080p30 on a 32GB card on a GoPro Hero (1)?

Have you try to go to the product web site and check?
http://gopro.com/support/articles/recording-time-in-each-video-setting

I know it is about Hero2, but i think the values will not change much. Be aware fully charged battery will power the camera for no more than 3 hours


What is the size of 1 minute video at 1920 x 1080 (60 fps)?

Try those calculators, they should do the trick.

http://www.digitalrebellion.com/webapps/videocalc


How do I remove excess video duration in ffmpeg when using lavfi?

You are feeding 21 seconds of audio from the video file and then applying adelay=3000|3000, hence 24 seconds. Add atrim=end=21 at the end to both your audio filterchains.

And

Add shortest=1 to both your overlays.


How to include proof of when a video was made, something that couldn't be be faked at a later date?

There isn't any way to do it within the video.  You can easily prove a video was made (or altered) after a particular time, but you can't prove that it happened before a particular time via the media itself, since you could edit things in from previous time to make it look that way.

The non-video answer would be to generate a signature of the video file and get it cryptographically signed by a reliable time stamping service.  This would prove that the video files had been unaltered since the time the stamp was applied.  Most Certificate Authorities can do this.  I personally use StartSSL because they are pretty cheap but reasonably well respected.

Alternately, you can have a document from a notary about when the video was made, though that won't prove it wasn't altered in some way.  The notary may have more legal baring than a particular CA's time server though depending on if anything causes a loss of faith in the Certificate Authority.