Exported the same video twice with the same settings yields files with different hashes

Yes, your observation is correct and everything works fine. Even if settings are identitcal, the file hashes will always be different.
The reason is quite simple: XMP metadata which is embedded in the files.
Such metadata entries which are often different are:

time stamps (not only the date but the time too)

creation date
modified date
metadata date

IDs

document ID
instance ID
original document ID

A bit of binary data in the header is different too. All the rest, meaning the actual video and audio data is the same. The encoding algorithms are working deterministic - that means, given the same input they produce the same output. At least those I've tried for my example. This doesn't have to be true in other cases.


Is there a way to improve h264_nvenc output quality?

h264_nvenc is able to encode in constant quality, at least from Pascal onwards. I had to do quite some digging around the internet to figure out how to properly use it, but finally found a working formula.
A command like below will record in constant quality, and the CQ value 26 will produce about the same but slightly better quality, measured with VMAF, as a libx264 encode with the following options: -vcodec libx264 -level 4.1 -profile:v high -tune film -preset medium -crf 23. The H264_Nvenc bitrate was about 19% higher than the libx264 encode, but it had a slightly better VMAF score. I made these tests on some 1080p60 game recording, but also on some 1080p movie trailers.
ffmpeg -i input.mkv -c:v h264_nvenc -preset hq -profile:v high -tune hq -2pass 0 -rc-lookahead 8 -bf 2 -rc vbr_hq -cq 26 -b:v 0 -maxrate 300M -bufsize 600M output.mkv

Important: Unless you set the Max rate and buffer size via -maxrate 300M -bufsize 600M, the CQ mode doesn't behave accordingly and lowering its value won't yield better results.
The Constant Quality mode is activated by specifying Variable Bitrate rate control together with a CQ parameter, a bitrate set to zero, and the above two parameters set to some large value which won't limit the output. Don't be afraid of those values, as bitrate will be quite good.


How to organize captured footage for documentaries before sending to editor?

If I was going to send this to an editor Or If I was going to be sent this I would like the following structure (this is all dependent on how they work but it helps)

 - Project name
   - Raw Video Files
     - Day 1
      - Cam A
      - Cam B
      - ...
     - Day 2
      - Cam A
      - Cam B
      - ...
   - Audio Files
     - Dialogue
      - "Audio recorder"
       - Day 1
        - Audio File 1
        - Audio File 2
        - ...
       - Day 2
        - Audio File 1
        - Audio File 2
        - ...

Im sure you can gather where im going with this, simple folder structure can make a whole difference to how easy and quick it can be to edit this my files at the top level look like

Project Name
 > Raw files
 > Audio files
 > project files
 > Exports
 > XML
 > DVD
 > ...

Hope this helps, there are many ways to organize this and many blogs, sites advising which is the best way but it comes down to how you want to work and what works for your filming and editing process within your company


Where can one find a current and definitive reference for video quality as it pertains to hosting HTML5 Videos?

What could do is show that Youtube transcodes to 4K at bitrates of ~20 mbps. You can use a tool like youtube-dl to check. Run youtube-dl -F URL So, your upload and download times will increase by a factor of 13-14, compared to the 1.5 mbps stream for 576p that you currently use.

Youtube is best placed in terms of expertise and motivation to minimize bandwidth use i.e. to determine the lowest bitrate that yields acceptable quality.


ffmpeg statement for Anaglyph of Red-Cyan Color

stereo3d is a video filter so it has to be specified via a filterchain or complex. Since you have two inputs, and stereo3d only converts a single input from one form of 3D arrangement to another, you'll have to combine the two image sequences first. For which, you can use the hstack filter, which will place the two sequences side-by-side.

So,

ffmpeg -i "left%06d.jpg" -i "right%06d.jpg" -filter_complex "hstack,stereo3d=sbsl:arcc" video_arcc.mp4

By default, image sequences are treated as 25 FPS and hence so will the output, in this case. If the framerate is different, say 24, then the beginning will be

ffmpeg -framerate 24 -i left%06d.jpg" -framerate 24 -i "right%06d.jpg


Here are a few resources I'm aware of.

The Video Quality Experts Group has a variety of test material available.
Big Buck Bunny, with a CC license, is often used as a test asset.
Tektronix at least used sell some test assets to complement their monitoring tools.
SRI has several test patterns and compliance checking assets for sale.


Are ffmpeg prores files reliable enough to be used in production/broadcast environment?

I've had no problems producing prores 422 HQ .mov files with ffmpeg on my Windows machine for Mac-encumbered clients, including delivery to TV Networks for broadcast. I have had some problems with prores 4444 but only when the files have alpha channels, however that bug seems to have been fixed recently.

I don't know if anyone has done any head to head tests with the results you get out of ffmpeg vs a native apple app or something like adobe media encoder. That would certainly be worth doing.


Pausing two keyframes at same position then moving to next one? After Effects

There are two types of interpolation for keyframes - temporal, and spatial. In plain English, temporal interpolation is how the speed of the motion is interpolated between keyframes - it's what you change when you ctrl or ⌘-click a keyframe, and spatial interpolation is how the motion path is interpolated between keys. Your problem is that AE is applying the wrong spatial interpolation.

Usually After Effects uses Bézier spatial interpolation between keyframes, meaning that they create smooth curves in space, which is usually what you want. However when you create a static pair of keyframes this causes problems - the layer overshoots the first keyframe and bounces back to the second.

To eliminate the problem bring up the keyframe interpolation dialog. You can either right-click the keyframe or use the keyboard shortcut alt⌘k (mac) or altctrlk (pc). Set the spatial interpolation to linear. This has the unfortunate side effect that any bezier handles you may have carefully created on the keyframe disappear. To make only one side of the keyframe have a handle you can select the keyframe in the timeline window, then alt-click it in the composition window (the cursor should turn into the V shaped arrow). In more recent versions of AE this will give you a bezier handle on the incoming and outgoing curves, not on the curve between the two identical keyframes. But because they're on top of each other you need to select them individually in the timeline first.

There's another way that I should mention, and this is by changing the temporal interpolation. If you right-click the first of the identical keyframes and choose toggle hold keyframe the motion will freeze until the next keyframe. If the keyframes weren't identical it would instantly jump to the second keyframe at that point.


There's several techniques you can use to emulate Google Glass' eyesight videos. The next best thing would probably be to buy a pair of camera (sun-)glasses. Judging by what you're trying to achieve, your best option is to buy any camera from pivothead, they all film full-HD 30fps video. Other options include the SunnyCam Glasses and the iVUE Camera Glasses. There's also the Zeal HD Goggles, but those are probably impractical in temperate environments.

Alternatives include the GoPro Hero 3 (Head-mounted camera, as you suggested), the ContourROAM2 (Waterproof) and the Braun SixZero (or any other head/helmet-mounted camera). If you're on a tight budget you might want to manufacture some sort of head-mounted camera yourself.


After Effects Audio Ahead of Video in Preview and Render

I think you’ve probably identified the cause. I’ve found when using mobile phone footage (And video conference captures) both premiere and after effects can incorrectly identify frame rates. If all the footage is around 59.93-60fps, I would try transcoding it all to 60fps first using a codec suitable for editing (like ProRes), making sure it’s all in sync after transcode, then re inserting it into your project (save a new copy of your project first though).


Very broadly speaking, you have a much easier experience obtaining permission if you are not making money from someone else's content.

Most copyright laws recognise 'fair use' -- a small quote or a clip that is proof of someone else having said something.  It is customary and advisable to put such clip in a box or window to show that the content is being referenced.  Fair use for a small portion of text or video is easily established than a picture, for a picture is the entire content.

For images, search engines usually have a license filter in the search. Usually, it errs on the side of caution. Unfortunately, you have to contact the original agency or person and obtain permission to use.
Youtube now has content signature comparison and will warn you that you are using someone else's content but will leave it up to the copyright owner to enforce it.

So, if it is does not fall under 'fair use' and is clearly someone else's copyright, you will have to track down the owner and obtain permission.


Software that I know of:

Virtualdub with Deshaker plugin:
http://www.guthspot.se/video/deshaker.htm
Sony Vegas Pro since version 10 has a built-in stabilization plugin
Depan for Avisynth - http://avisynth.org.ru/depan/depan.html - it can get quite complicated but there are sample scripts to help getting started.

Youtube can detect if the footage is shaky, though it's not always working so well and it applies to the whole video.
My personal favorite is the Virtualdub route. Just remember to save it to a lossless format if you plan on editing it further.


Convert high frame video to slow motion video

You can use ffmpeg, a free command-line tool, to do this:

ffmpeg -i input.mp4 -vf setpts=8*PTS -r 30 -crf 18 output.mp4

This slows down the video 8 times and output is 30 FPS.


Bad video camera + little money = decent video quality

The difference in brightness outdoors compared with indoors is much greater than you'd think due to the way your brain compresses the dynamic range. If you've ever been on a location shoot that's been properly lit for video you'd see the difference - it hurts your eyes!

I'm afraid the point here is that you're not going to recreate outdoor lighting for that price range. You are better off trying to rearrange your shooting to make the most of natural light.

If you really need to shoot indoors, getting some work lights and using hard, direct (undiffused) lighting will give you the biggest bang for buck. It's a distinctive look that can work well.


Print to file: Details of every NAL unit in raw H.264 file

You can use the trace_headers bitstream filter in ffmpeg

ffmpeg -i in.264 -c copy -bsf:v trace_headers -f null - 2> NALUS.txt

The text file will have data like this,

[AVBSFContext @ 00000000027d3580] Packet: 102 bytes, no pts, dts -31999, duration 40000.
[AVBSFContext @ 00000000027d3580] Slice Header
[AVBSFContext @ 00000000027d3580] 0           forbidden_zero_bit                                          0 = 0
[AVBSFContext @ 00000000027d3580] 1           nal_ref_idc                                                10 = 2
[AVBSFContext @ 00000000027d3580] 3           nal_unit_type                                           00001 = 1
[AVBSFContext @ 00000000027d3580] 8           first_mb_in_slice                                           1 = 0
[AVBSFContext @ 00000000027d3580] 9           slice_type                                              00110 = 5
[AVBSFContext @ 00000000027d3580] 14          pic_parameter_set_id                                        1 = 0
[AVBSFContext @ 00000000027d3580] 15          frame_num                                                0001 = 1
[AVBSFContext @ 00000000027d3580] 19          pic_order_cnt_lsb                                      000100 = 4
[AVBSFContext @ 00000000027d3580] 25          num_ref_idx_active_override_flag                            1 = 1
[AVBSFContext @ 00000000027d3580] 26          num_ref_idx_l0_active_minus1                                1 = 0
[AVBSFContext @ 00000000027d3580] 27          ref_pic_list_modification_flag_l0                           0 = 0
[AVBSFContext @ 00000000027d3580] 28          luma_log2_weight_denom                                      1 = 0
[AVBSFContext @ 00000000027d3580] 29          chroma_log2_weight_denom                                    1 = 0
[AVBSFContext @ 00000000027d3580] 30          luma_weight_l0_flag[i]                                      0 = 0
[AVBSFContext @ 00000000027d3580] 31          chroma_weight_l0_flag[i]                                    0 = 0
[AVBSFContext @ 00000000027d3580] 32          adaptive_ref_pic_marking_mode_flag                          0 = 0
[AVBSFContext @ 00000000027d3580] 33          cabac_init_idc                                              1 = 0
[AVBSFContext @ 00000000027d3580] 34          slice_qp_delta                                      000010011 = -9
[AVBSFContext @ 00000000027d3580] 43          disable_deblocking_filter_idc                               1 = 0
[AVBSFContext @ 00000000027d3580] 44          slice_alpha_c0_offset_div2                                  1 = 0
[AVBSFContext @ 00000000027d3580] 45          slice_beta_offset_div2                                      1 = 0
[AVBSFContext @ 00000000027d3580] 46          cabac_alignment_one_bit                                     1 = 1
[AVBSFContext @ 00000000027d3580] 47          cabac_alignment_one_bit                                     1 = 1

You'll have to parse the file to count frames.

Alternatively, H.264 Stream Analysis appears to be a frontend for h264_bitstream. Latest source available from https://sourceforge.net/projects/h264bitstream/files/h264bitstream/0.1.9/. It can be easily compiled on Windows under MinGW/MSYS2.


How to make a project for compilation videos?

Yes, in Premiere, you can create a master sequence consisting of nested sequences and apply motion and effects to those nested sequences within the master sequence.

And swap footage within those nested sequences as desired.


best software for multicam video production

Premiere is your best option unless you plan on spending a boatload (thousands and thousands) on an Avid system.  I'd suggest working on smaller sets of cameras at a time and then working off the combined feeds.  You can use multicamera editing mode with several cameras at a time, make the best choices out of those and then run each of those sequences in to another multicamera sequence to further resolve them.

The process is going to kind of suck no matter what system you do it on because it is a boatload of synchronous footage to go through.


I solved my own problem after some more trial and error. For awhile it looked like the fact that I was using Mental Ray shaders combined with general shaders was the problem, but that didn't really make sense so I kept tweaking. It turns out that an image plane I had tied to my camera was the problem. The image on the plane never rendered out, so I assumed the plane wasn't affecting the rendering, but it turns out it was showing up as a black plane when rendered. I deleted the plane for my render and it works fine now.


What software can we use to create this slideshow video

You should give a chance to Sony Vegas 8 or newer. In Sony Vegas you can place as many images as you wish and make it "fly in" or "fly out" over a background which can be a solid color, gradient (both self-generated) and/or a background image.

The process itself is quite easy. You set the background in the timeline for the duration that you need. Then simply add as many tracks as you need for each image that you wish to get animated over the background, place the item in the timeline, enter the "Pan and Crop" function of the timeline and create the movement that you wish.

See this video for a comprehensive explanation about the Pan and Crop function in Sony Vegas.

In Sony Vegas you can create per-track and/or per-event motion by using the proper tools.

If you are using Linux you may find KDEnlive as a good alternative for Sony Vegas.

Good luck!


Where can I find design specs for 6mm to 22mm display signage?

There's no standard resolution for such displays. They're generally made up of a collection of individual (usually square) panels or "tiles", of say 16 x 16 LED pixels. You can construct a display having hundreds of tiles horizontally but only a few tiles vertically, like the Fremont Street experience in Las Vegas, which has an aspect ratio of about 14:1 (2596 x 184).

Plus, displays can have any shape, not just simple rectangles. Fremont Street is curved, and I've worked with diamonds, cylinders, triangles, skewed pyramids and truncated circles.

There's no perfect way (that I've seen) of simulating the pixel grid. The best you can do is work in the pixel dimensions supplied by the display company, applying masks as needed for irregular shapes, and field test with any material that needs fine lines or small text. Assume for the most part that the intended viewing distance will allow the coarseness to 'average away'.


How much is a good framerate for slo-mo recording?

In tecnical terms of Slow Motion, you can record at any speed, the fact is that actually slow motion... is achieved when each film frame is captured at a rate much faster than it will be played back.The technical term for slow motion is overcranking which refers to the concept of cranking a handcranked camera at a faster rate than normal (i.e. faster than 24 frames per second).
A third technique that is becoming common using current computer software post-processing (with programs like Twixtor) is to fabricate digitally interpolated frames to smoothly transition between the frames that were actually shot. Ciberlink PowerDVD uses that interpolation for ex.

Answering your question, you can achieve slow motion with any video recorder, the more frames per second, the better or smoothly... and of course you can use software post-processing to smooth frames out.

Hope this answer your question.


Are there only a few standard video frame rates?

There are several "standard" frame rates, but there are getting to be so many that supporting arbitrary framerates is easier than specifically supporting many specific ones.  This is especially true for software players, like VLC.

More and more support exists for VARIABLE fps.  (VFR, variable frame rate).  This is where the interval between frames within the same video isn't a constant.  Many video container file formats (like Matroska (.mkv) or MPEG-4 (.mp4, closely related to Apple's .mov)) don't even store a FPS number, but rather a time base (e.g. 1/30th of a second), and then each frame has a timestamp as a multiple of that time base.  It just so happens that the interval between each frame is one or a small integer number of units of the time base in a CFR (constant frame rate) video.

Security-camera footage with near-duplicate frames dropped would be an obvious use-case for VFR.  Even moreso if it's being compressed with a simplistic video codec that doesn't take good advantage of temporal redundancy (with inter (p and b) frames).  (play around with ffmpeg -vf mpdecimate to drop near-dup frames.  Use -vsync 2 if outputting to mp4, because for some reason it isn't the default for that muxer, but it is for mkv.)

Another case is modern smartphones.  For example, my brother's Moto G (2nd gen) records VFR videos.  It lowers the frame rate when the sensor needs more light.  Some of the output from running mediainfo on an mp4 created by the phone's software, recorded indoors:

Bit rate                                 : 9 999 Kbps
Width                                    : 1 280 pixels
Height                                   : 720 pixels
Display aspect ratio                     : 16:9
Rotation                                 : 90°
Frame rate mode                          : Variable
Frame rate                               : 16.587 fps
Minimum frame rate                       : 14.985 fps
Maximum frame rate                       : 30.030 fps

Playback of a single VFR video stream is not hard.  The software just gets the next frame ready to display, sleeps until it should be displayed, then wakes up and displays it.

Things get a bit more complicated when you take into account the fact that humans can only see video frames when a monitor displays them.  VFR monitors exist, but are still rare.  (google for g-sync freesync).

Changing the displayed image while it's being scanned out to the monitor results in ugly tearing of the video (commonly seen when playing a game with vsync off).  This limits a player to changing the displayed image at 50 or 60Hz.  (CRTs support arbitrary vrefresh rates, within a range, but it's complicated to cook up modes with all the timings correct, so most people just used a few fixed refresh rates.  And now people have LCDs which only support a fixed refresh rate anyway.  Until freesync monitors are more widespread anyway.  I'm really looking forward to that. :)

So with video frame rates that aren't a multiple or a factor of the monitor refresh rate, some frames will be displayed for 3 monitor refreshes, and some for 2, for example, even if the video is meant to be at a constant 25FPS (on a 60Hz monitor).

Things get more complicated when you want to work with multiple clips and fade between them, or picture-in-picture, or various other effects.  It's a LOT easier to write video editting software if you can assume that all the clips have a new frame at the same time.  (They force clip alignment to snap to whole frames).

This is why NLEs (like kdenlive or pitivi, to pick random Free software examples), are more likely to force you to a fixed FPS, and drop/duplicate frames from your clips to make them match that frame rate.  The CFR you choose can be arbitrary, but it typically has to be constant for the whole "project".

(Do any NLEs fully work with VFR clips, and produce VFR output in that case?)

So in summary, once we have variable-sync monitors and OSes, the only thing holding us back will be video editting, I guess.  And broadcasting, since apparently CFR is a big deal for that, too?

In case you're wondering, the 29.970 (actually 30000/1001) and 23.976 (actually 24000/1001, from telecining) annoying non-integer frame rates are the fault of color NTSC.  search for 1.001.  If only they'd been willing to risk a few B&W sets not being able to handle an extra 0.1% frequency for the audio subcarrier, the world would have been spared this nonsense.  (I think I saw another article somewhere that made it sound more like many sets would have been fine, but they weren't sure about perfect compat.  Wikipedia makes it sound like no sets would have handle a 0.1% higher audio subcarrier.  IDK the facts.)

Annoying frame rates are one of the lesser sins of broadcasting, though.  It's really interlacing that's been the bane of video quality on modern (all pixels lit at once) screens, and that wouldn't have changed.  I still don't get why interlacing was kept around for HDTV.  Why was 1080i60 was ever defined, instead of using 720p60 to get the same temporal resolution for sports and stuff?  It's similar to 1920x540p60, but with a stupid vertical offset between odd and even fields that requires a lot of computation on the receiving end to make it not look horrible.

edit:

For your use-case, I'd absolutely suggest archiving at the native FPS.  Don't throw away any information by dropping frames.  Don't dup frames and make your files bigger (or make your h.264 encoder spend more time noticing the duplicates and outputting a frame full of skip macroblocks that only takes 20 bytes for the whole frame).

In the future when we hopefully all have freesync displays that can play any framerate, you'll want to undo your pullup to 24fps so your video plays more smoothly!  Or if freesync somehow doesn't catch on, or the display that comes after LCDs is CFR, then rate conversion is probably best done at playback time anyway.  It's not like 24fps even plays perfectly on a 60Hz monitor.  (I don't visually notice the fact that some frames are displayed for 3 * 1/60th while some are displayed for 2 * 1/60th, but it's true).

If you're having problems with Quicktime, then IDK.  Maybe make sure Handbrake is making files with the right framerate set in the h.264 bitstream, as well as the container.  (Yes, h.264 headers can apparently store a frame rate, separate from what the container says.  See the docs for mkvmerge --fix-bitstream-timing-information.  And try using it with --default-duration 16fps to make an mkv file.  Then mux that back to mp4 and see if that fixes quicktime?)  Or maybe there's a way to do it with mp4 tools in the first place.  See for example: https://askubuntu.com/questions/370692/how-to-change-the-framerate-of-a-video-without-reencoding

I can guarantee that arbitrary frame rate mp4 is valid, and even variable framerate mp4 is valid.  If Quicktime plays it wrong, it could well be Quicktime's fault.  Or maybe Handbrake's fault for making the file wrong.  I usually just use ffmpeg directly, because I'm a command line ninja.


avconv grab DVD with chapter seperations - dvd_nav_packet

The chapter marks are part of the DVD metadata that's on the disc (or its ripped contents). It's not contained in the nav packets.

If you want to get the chapters, you're going to have to use a separate application to get them out. There's two applications that I know of that can do it -- dvd_info (which I wrote, see github) and ogmtools.

mkvmerge supports two chapter formats -- the spec one of the XML with lots of detailed information in it, or the simplified OGM format designed for that container, which is a simple chapter name + start time format on each line. I recommend using that one.

Using those two apps, here's how, assuming you're using track 1.

$ dvd_info --ogm -t 1 /media/cdrom/video_ts > chapters.txt
$ dvdxchap --title 1 /media/cdrom/video_ts > chapters.txt

Here's a sample output:

CHAPTER01=00:00:00.000
CHAPTER01NAME=Chapter 01
CHAPTER02=00:00:13.500
CHAPTER02NAME=Chapter 02
CHAPTER03=00:06:04.867
CHAPTER03NAME=Chapter 03
CHAPTER04=00:13:42.667
CHAPTER04NAME=Chapter 04
CHAPTER05=00:22:37.867
CHAPTER05NAME=Chapter 05
CHAPTER06=00:28:29.933
CHAPTER06NAME=Chapter 06
CHAPTER07=00:28:42.433
CHAPTER07NAME=Chapter 07

I don't know how to get the chapter metadata in a matroska file using libav directly, or if it even supports doing that, but mkvmerge certainly can.

$ mkvmerge -o track1.mkv --chapters chapters.txt track1.vob

On a side note, if you don't want to cat the VOBs into one giant file, you can use dvd_copy to extract it and dump it directly into a MKV. You'd still have to mux in the chapters, but it would skip the step of having to use cat. Note that I've only tested this with libav:

$ dvd_copy -t 1 /media/cdrom/video_ts -o - | avconv -i - -codec copy dvd.mkv


You have two options, one, install software on the presenter's system that can encode and send a video feed to another system.  This is in-effect going to be a screen casting application, even if the feed is only forwarded to another system to be packaged.

The other option is to actually capture the raw output from the presenter's system through a frame grabber or video interface of some type.  This is the least invasive way, but then have no idea about cursor position or the like.

There is no solution that can connect to another computer and grab whatever is on their screen without putting software on that computer.  You can however do something minimally invasive like putting a VNC server that can run from a USB stick without installing and then connect to that VNC server and run the screen capture off the VNC client on a system you control.


libx264 is a very efficient encoder, so that bitrate isn't unusual. In fact, it's on the higher side, but since you're capturing a game, I expect there is constant motion involved, and your preset is ultrafast which disables some of the aggressive compression.

When you say 80MB/s, I believe you're thinking of uncompressed full raster i.e. 1280 x 720 x 12 bits/pixel x 60 fps. Lossless does not mean uncompressed, just like there can be a compressed ZIP of a binary program.

BTW, the -framerate 60 goes before -i video="Game Capture 4K60 Pro Video 01" as it's an input option.


how to do the video commentary with you in the corner of the screen?

Since you didn't answer @Ryan's question, I'll assume your talking about video editing, not live streams.

What you're talking about is a very basic editing technique called a video overlay. Obviously, you're going to need two video recordings for that, one of which is the screen capture. There are several pieces of software out there that will record your computer screen while you play your game (or whatever you're doing), e.g. fraps. The second video is the one that shows you. To record that, you will need either a camera or a webcam (careful with the latter, those usually provide poor quality). You record yourself, copy the video files to your computer (or connect the camera to your computer and have it save the recording directly to your hard drive) and import them to iMovie. Then you just have to put one video on top of the other and you're done – even though iMovie is a consumer-centered software with not that many features, it's sufficient to do video overlays. Here's a simple tutorial:

If you want to do that as a live effect while streaming, the required software and setup is a bit more complicated – there are several good tutorials out there.


The timecode_rate value is rounded and then applied, so 0.2857 gets rounded down to 0, which is considered invalid. That error message should be refined.

Since you seem to want timecode value to increase by 0.2857 after each 32 frames, you can supply a custom text value

text='%{e\:0.2857*n/32}'

Remove the timecode and timecode_rate options.


Can I shoot in 16:9 then change it to 4:3?

Of course you can set your project up so that it will output a 4:3 video. However, keep in mind that there are only two ways to achieve this:

Nr. 1 You crop the video, which means you will lose stripes of the video at both the left and the right side.

Here's an example:

Nr. 2: You resize the 16:9 input video so that it fits in the 4:3 output video. I wouldn't recommend this though, since the video and everything in it will be deformed, which looks completely aweful.

So if this is your input:

It will result in this output:

Both options result in a quality / information loss. How about shooting in 4:3 at a higher framerate? You could easily lower the framerate in editing to achieve your desired effect ...


Where to place a camera to record Swimming

For the swim you really only have one option - to wear a light helmet of some kind to get the camera on the top of your head.

Anywhere else and it will not show anything useful (too much splash) or will cause drag (eg chest mounted) - look how much of the body is underwater:

If you think you are really good, point it backwards. You will get a better view, with less splash, and if you are in front, the shots you will get of the rest of the pack could be really good.


Can I swap out compositions, or control a composition's layer visibility via the timeline?

You can replace a comp in the timeline with a comp from your project tab:

Select a comp in the project tab
Select the layer in your timeline that you want to replace
Hold down alt
Drag and drop the new comp from the project window

It will replace the layer in the timeline, maintaining all the settings on that layer.
You can show or hide a layer using the Opacity control on each layer. Select the layer and press T to reveal them (remember it as "opaci-T").
Then you can make a keyframe on that layer to animate it on or off (hold keyframes are useful for this).
You could also pre-comp all your layers onto a single layer, then use Time remap to select which frames appear when (and use the Loop expression on the time remapping to loop sections if necessary).


Is it possible to embed VTT subtitles & chapters in webm video?

Edit: It seems that WebM now supports VTT subtitles. See the link below for detailed information.
If you want to add subtitles to a video on a web page, have a look at the HTML5 'track' element. It allows adding subtitles without muxing them into the video container. More details here: https://developer.mozilla.org/en-US/docs/Web/Apps/Fundamentals/Audio_and_video_delivery/Adding_captions_and_subtitles_to_HTML5_video

WebM doesn't support subtitles nor chapters right now so you won't be able to embed them without creating a WebM file that is out of specs.
You will probably want to remux your video into mkv and then convert your VTT subtitles to SRT and mux these into your mkv aswell.

From http://www.webmproject.org/docs/container/

  Initial WebM release does not support subtitles.

  WHATWG / W3C RFC will release guidance on subtitles and other overlays in HTML5  in the near future. WebM intends to follow
  that guidance. Ref: WebVTT.


Digital video cameras optical zoom vs lenses

Your facts mislead you. Lens magnification and size have nothing to do with video or stills. They have to do with sensor-size.

Your DSLR has a large sensor and requires a large lens. The digital video camera you refer to has a small sensor and requires a small lens. You can very easily pick some random examples to show the opposite! Take a Canon Powershot SX50 HS, for example, which has a 50X optical zoom and a Sony NEX FS100U which has a sensor larger than your Nikon and will require an even larger lens to achieve the same magnification. This makes it impossible to get the kinds of zoom seen on small cameras without the lens requiring its own transport mechanism!


I am getting "Stream specifier ' ' in filtergraph description" in ffmpeg

Your command is missing the -i token for the image input, so it should be

ffmpeg -loop 1 -framerate 24 -t 10 -i image.jpg -f lavfi ...

However, for the actual task at hand, the concat filter is not required.

ffmpeg -loop 1 -framerate 24 -t 10 -i image.jpg -f lavfi -t 10 -i anullsrc out.mp4


What is the name of the device used in live action filming that includes information like scene, take and roll and has a part that can snap together?

It is clapperboard: http://en.wikipedia.org/wiki/Clapperboard

used in filmmaking and video production to assist in the synchronizing of picture and sound, and to designate and mark particular scenes and takes recorded during a production


Light wavelengths and color reproduction / grading

You are facing a low CRI index.

https://duckduckgo.com/?q=Color+Rendering+Index

CRI is the Color Rendering Index, and this means, effectively that you do not have enough light across the spectrum.

Some lights emit only portions of it, and our brains adjust the color to what they think the color should be, but as a mechanical/electronic device, a camera is more limited to what actually is receiving.

Look for higher CRI lights. The scale limit is 100, meaning that the light emission spectrum would be the same as the daylight. So the closer to this number the better color you will get. For practical purposes, a CRI above 85-90 could be decent enough. One above 95 can be considered a "Pro-level"

If you search a store, a lot of led lights mention the CRI value, use those terms on a search, for example on the Amazonian river store "LED LIGHT CRI".

  lights is not uniform across the spectrum?

The spectrum does not need to be uniform, it just needs to be "uniform" enough compared to daylight spectrum (which is not uniform at all)

  It looks almost colorless when I reduce the red component

You need to differentiate the CRI to the color temperature. You need additionally to check two factors.

The color temperature of the Light (Warm, cold)
And if you are setting your white balance correctly on camera.

It also could be corrected to some degree using a custom color profile or using some "pro-grading" program. Give Davinci Resolve a Try.


Audio and Frames Not in Sync in RAM Preview

Try to convert your video into ProRes422. I guess the video codec of your source material is using some sort of compression, that After Effects is having problems with and is loosing sync.

On OSX ProRes422 comes with Quicktime or can be downloaded as a free Update for Quicktime. But if you only have a Win7 computer to work with, you can use FFMPEG: it supports ProRes422.


does h.264 have separate audio and video

You don't need to specify "separate tracks", just the audio and video specs you accept. All common containers will handle multiple disparate tracks including video, audio, text (captions etc). h.264 is a video codec; you could choose (or allow) any of several audio codecs.


Does canon EOS 1000D support video recording?

It cannot officially record video, but there is an open source project to allow recording direct to a computer.

Source

Given that it doesn't support video natively then there won't be a built in microphone to record sound. If you went with the open source software you'd have to record the sound separately and sync it afterwards - which is not a straightforward process.


What exactly does "Ethernet-capable HDMI cable" mean?

No it does not mean you can do anything wirelessly - it is a cable - and it isn't likely to help you stream anything to it either, unless you have a requirement for HDMI devices to share a network connection.

Version 1.4 of the HDMI standard allows for 100Mb ethernet to be transmitted along the cable between to HDMI 1.4 capable devices.

Check out the HDMI wikipedia page for some basic info


Masking out the video background in Sony Vegas

chroma key choose a colour*drag) then take eye dropper and select background in the preview window


using -force_key_frames in ffmpeg with libx265

ffmpeg's libx265 wrapper is very minimal, and doesn't pass on very many settings.  e.g. -pass 1 requires manually setting -x265-params pass=1.

Also, if x265 is anything like x264, don't use ultrafast except for lossless or for testing things.

sorry for not taking the time to dig this up myself, but have a look and see if you can get your desired I frame locations into x265-params.  Probably not, though.

If you want to hack some C code, have a look at libx264.c and libx265.c, and maybe you can see how to ffmpeg sends frame-type requests to x264.  And maybe you can port that to the libx265 wrapper.


Why are these flickering lines appearing during a fade to black in my Premiere render?

I believe what you reference is called "artifacts".

Those phenomenons are a result of compression. Vimeo does not use the raw file you upload as playback. Instead, the file is converted and compressed for storage-purposes mainly. This might be one reason as of why this is appearing.

The second possibility is that your footage was not recorded at a deep-enough bitrate, and so it seems from the information you gave. h.264 is always a lossy codec, which means that you're gonna throw away a chunk of data when writing a file in h.264. I know that the gh5 is able to record in avchd, which would be a far better choice in terms of image quality compared to mov h264 or mp4 h264. Try recording in that format.

Lastly, using a flat profile could safe you some extra-information in those parts that get compressed could help you. The gh5 has a vlog-L profile as well as a Cinelike D one. These are so called "flat profiles" which will lower the contrast and saturation at first, but give you the ability to adjust contrast and brightness afterwards. Recording in a flat profile captures more information in very bright or very dark areas, which would otherwise get lost. Trying this might also improve your results.

However, Vimeo, youtube, Clipfish, hell what ever Streaming-Service you use - compression will take place, which means that your video will look worse there than in the original file. Depending on what you're planning on the long run (for example sending a video to a client) it might be a better idea to straight up upload the prores4444 or DNxHR or similar near-lossless codec and send the link to the client (for example via ftp-server) so he/she/it can download it directly without the use of 3rd-party streaming-services.

Hope my answer was helpful, happy filming!


How to change every black pixel to a special color?

You can use the LUT or GEQ filters for this.

e.g. with LUT

ffmpeg -i myVideo.avi
       -vf
       "yadif,format=rgb24,
        lutrgb=r='if(eq(val,0),3,val)':g='if(eq(val,0),3,val)':b='if(eq(val,0),3,val)'"
image%d.png


Use the frame guides built into whichever camera you use, and set the guides to 4:3.  Both cameras you mention have them.  When you're shooting, compose your image inside the frame guide.  The camera will record outside of that area, but when you edit, you'll crop the image back down to 4:3.  The extra pixels around the edges allow you to do things like; recompose if necessary, correct your horizon, add or remove lens distortion, add or remove camera shake, etc.

I haven't used the A7 enough to remember where the frame guides are in the menu structure (Sony menus are famously awful.  I still have nightmares about switching to/from HFR RAW on the FS700.), but on the BMPCC4K it's dead simple, just tap the reticle icon on the top left corner of the screen, and select 4:3 from the menu that appears, and flip the toggle on the bottom left to "ON".


'"How to change the song in one time?" Audio Spectrum Visualizer (After Effect)

Using the Audio Spectrum plugin in After Effects, you can reference a layer (using the "Audio Layer" parameter) on your timeline as an audio source. To update all referenced audio sources in your project at once, you can precomp the audio track and use the new nested precomp as your audio source instead.

  1) On your timeline, highlight your audio track. Hit CTRL + Shift + C (CMD + Shift + C on OSX) to Pre-compose the audio.

  2) In the Pre-compose menu, name it "Audio Reference" or something similar, then select "Move all attributes into the new composition" and hit "OK"

  3) This new composition will be added in your Project panel. Use this composition instead of your audio file when working in After Effects.

To update the audio file project-wide with a couple of clicks, just open the reference composition you created and swap out the audio file inside. This will change every instance of that composition in your project.

Hope this helps! Let me know if you need clarification.


Increment a number, based on number of keyframes in After Effects?

Yep, just do

var p = <pick whip the property with the keyframes here>;
var k = p.nearestKey(time);
if (k.time <= time){
    k.index; //key is in the past
} else {
    k.index-1; //nearest key is in the future, return the previous key
}

On the first line you have to reference the property with the keyframes. The easiest way is with the pick whip (the curly thing in the expressions buttons). Drag it to the property you want to reference.

So the first line should look something like this:

var p = thisComp.layer("Pale Gray-Magenta Solid 2").effect("Slider Control")("Slider");

or

var p = transform.position;

Don't forget the semi-colon at the end.


YouTube message suggesting wrong compression settings (Wondershare Filmora)

What that message likely indicates is that the MP4 produced by Filmora does not have its MOOV box at the beginning of the file. The MOOV box has metadata about the audio and video streams contained in the MP4.

Why this matters is that Youtube speeds up processing by breaking the uploaded video into segments, processing those segments in parallel, and then joining the processed parts into a whole video again. If the MOOV box is at the front of the file, Youtube is able to start creating the segments and dispatch them for encoding as the file is being uploaded. If the MOOV box is at the end of the file, it has to wait for the whole file to be uploaded before it can start processing.

A cursory search did not reveal how to get Filmora to place the MOOV at the beginning of the MP4.


Why Premiere Elements exported project is "jumpy"?

Make sure you turn each clip's setting to deinterlace on. If Elements has flicker removal, turn that on as well. Make sure you scale your clips to the right size. But if your source is 10 FPS, converting it to 29.97 is not going to create extra frames, unless you use a plugin or effect like frame blending or twistler. You will simply be playing back 10 FPS at 29.97, meaning each original frame will appear for (approximately) 3 frames at 29.97. 10 FPS is jumpy. 24 was set as the standard a century ago, after 18 FPS had been used for some time and was ruled too hard to watch (flicker). Thus why all the old sports movies look like they run fast... because they play them back at 24. Hope that helps.


How do I achieve a "throbbing light" effect in After Effects?

The pulsating light is just the intensity of the light varying over time. There are various ways of doing that, you could keyframe it (if you had nothing better to do), you could use an expression like wiggle, or the "the wiggler" tool (if you're old school), or you could control it with the audio level of a layer that has audio.

If you're trying to drive the intensity of the light from the audio, then you need to first convert the audio levels to keyframes. Right-click the footage with the audio, and choose Animation>Keyframe Assistant>Convert Audio to Keyframes, or with the audio layer selected go to the Animation menu in the menu bar and choose *Keyframe Assistant>Convert Audio to Keyframes**. Then you can use those keyframes by either copying and pasting to your light's intensity property (and tweaking the values in the graph editor), or using an expression. This answer details how you do that.


The reason is because HLS as a source is really just a static file (a bunch of .TS packets).  This requires you feed the new ffmpeg process (in your case RTMP) at x1 speed, or real time.  You can do this with the -re flag before the input.


Text control is very limited in after effects. There is no functionality in the Character Panel to achieve a strikethrough at the moment.

Using Illustrator

For better text control I'd suggest create your text in illustrator instead:

and import the illustrator file into after effects afterwards:

Note: Editing the text in illustrator is still possible.

Using a shape layer

In order to create a simple stroke above your Text Layer:

Enable the Pen Tool (G)
With no layer selected, click into the Viewer (this will create the 'first point' of the stroke)
Hold down Shift to make sure that the line, which you are going to create is 'straight'
Click into the viewer again to set the 'end point'

This will create a new Shape Layer. If the layer is selected you can adjust the 'stoke color' and the 'thickness' in the Tool Bar:

Another way is to roll out the Properties of the layer by clicking on the tiny triangle > left beside the layers name, go to Contents > Shape(Number) > Stroke(Number) to adjust the 'color' and the 'width'.

However a shape layer provides much more control in terms of animation:

Add a Trim Paths property
Create a first keyframe by clicking on the stopwatch of the End value and set it to 0
Move a few frames forward
Create a second keyframe and set End value to 100

Related: https://graphicdesign.stackexchange.com/questions/49643/how-to-use-after-effects-trim-path-with-an-illustrator-path/49975#49975

Result


Does using component cable help improve video quality?

It won't make a difference because your box is SD. No amount of signal inserted in it would make it look HD. To show HD, you need HD ready equipment.


ffmpeg copy highest quality audio track of a specific language

A map option will select all streams matched by the specification. The 'best' stream is only selected in the absence of any map options.

So, you'll need a two-stage process to do this:

ffmpeg -i in.mkv -map 0:a:m:language:eng -vn -acodec copy -f nut - | ffmpeg -f nut -i - -c copy output.flac

The first ffmpeg process sends all English language audio streams to the 2nd ffmpeg process, which will select only the 'best' among the received streams for output.

If you want to keep metadata, and not worry about the codec of the input file, you can change your output to .mkv


Apple is dropping support for the player, so no new releases, but the format remains and can be decoded by recent versions of CC without needing Quicktime to be installed. See

http://blogs.adobe.com/creativecloud/quicktime-on-windows/

  Adobe has worked extensively on removing dependencies on QuickTime in
  its professional video, audio and digital imaging applications and
  native decoding of many .mov formats is available today (including
  uncompressed, DV, IMX, MPEG2, XDCAM, h264, JPEG, DNxHD, DNxHR, AVCI
  and Cineform). Native export support is also possible for DV and
  Cineform in .mov wrappers.

http://blogs.adobe.com/creativecloud/apple-quicktime-on-windows-update/

  Today we’re pleased to announce that Adobe has been able to accelerate
  work that was already in progress to support native reading of ProRes.
  This new capability is fully licensed and certified by Apple, and
  barring any unforeseen issues during pre-release, these fixes will be
  included into an update to the relevant products in Creative Cloud
  shortly.


What is the most effective way of slowing down footage?

Depending on how much you are looking to slow down.  Interpret as 50fps, and then once in your timeline, say it is a 25fps timeline.  Then you can stretch the footage using time remapping, then you can turn on frame blending to the solid line...this will be good in most instances up to about 25% speed of original...

Less than that the same, 25fps timeline, interpret footage at 50fps, then use twixter to get that super slomo feel.  Not that twixter does not always work and is going to give varying results based on the footage.


You need to use state e.g.

ffmpeg -i src.png
 -vf zoompan=d=300:z='if(gte(zoom,2)+eq(ld(1),1)*gt(zoom,1),zoom-0.04*st(1,1),zoom+0.04+0*st(1,0))'
o.mp4

This expression zooms from zoom=1 to zoom=2 in steps of 0.04. Remember, zoom is initialized to 1. The above will create 6 loops.

In st(store) and ld(load) functions, the first argument is variable id (0 to 9), and the second is the value.


Using the Rotobrush Tool with a Graphics Tablet in After Effects

The roto-brush tool is a painting process - you paint green in the areas you want to rotobrush, red in the areas you don't, then tidy up edges with the feathering tool. See example here:


Open source video editing software compatible with Linux

Light Works is supposed to be pretty good. It's been used on some pretty big budget projects so it's definitely worth a look. I have tried it myself though.

https://www.lwks.com/

EDIT
This is not open source software but it is freely available.


Final Cut Pro X multiple audio channels auto muting

To my knowledge, there is no feature or even a plugin what can monitor one audio channel and adjust another. I would see that as it is the job of the editor or sound engineer. That's the reason you get paid the big bucks I guess.

Better microphones definitely can help. If you get microphones which have a very distinct range you can limit the echo effect. You might consider asking in sound engineer group what microphone would be best for your situation.


how can I flip from camera to screen recording

You have two main options I can see, first one is to take a look at Open Broadcaster Software Project.  This project is free and open source and is targeted at individuals trying to stream primarily, but it does have good support for both a video capture device and a screen capture.  I believe it is possible to configure a shortcut key for swapping sources and it does support local recording.

For this option, you will also need a way to capture the video from the camera.  You can either use a webcam hack to pull the preview video from EOS Utility using some third party drivers (Covered in more detail here) or you can purchase an HDMI input device, such as a Matrox MXO2 or BlackMagic Intensity (not free or even particularly cheap, but necessary if you want to make use of the HDMI out of your camera.

Alternately, you can just use standard screen recording software and record the video independently.  You can then edit them together after the fact.  To avoid sync problems, you can start by showing the camera the screen and opening and closing a window to sync to later.  This is the cheapest option as it can be done without any additional investment using entirely free tools.  It is also the highest quality option as non-real time encoding and hardware assisted encoding (such as on the camera) does a far higher quality job than software based real time encoding.  It also allows you to be the most selective about when you switch sources and preserves feeds of both sources in case you want to make changes later on.


Best transcoding path using Sorenson Squeeze for AVCHD video?

With NTSC DV format (854x480), you are throwing away resolution. I'd suggest I-frames only MPEG2 with a good bitrate (about 5MB/s). I don't know Squeeze, so I don't know what parameters are available. If you post a screenshot of the export/convert dialog, I may be of help.


Have to reduce the video size with losing the quality

By nature, reducing the size of the video (either by bitrate, by resolution or both) will reduce the quality of the video.  You can minimize the loss by using good compression algorithms from high quality sources with proper settings, but there will always be quality loss with additional compression, even if minimal.

Without knowing more about the type, length and resolution of your video, it isn't possible to give the best advice, but using 2 pass VBR H.264 video is a fairly standard compression algorithm to use.  2 pass VBR will adjust the rate of data use to help account for differences in complexity of the video and make better use of the data you allocate to it, but it is still necessary to allocate sufficient data rate or the quality will deteriorate.

If the video is HD, then it would have to be pretty short (under one minute) to stay under 74mb without pretty significant quality loss.  Dropping the resolution will similarly greatly reduce the quality, though depending on the level of compression, it may be less blocky.


ffmpeg: how to convert to DNxHR in Windows 10?

There's a single decoder/encoder which reads/converts to both DNxHD and DNxHR.

You have to set the correct profile switch. Available options are

 dnxhd                        E..V....
 dnxhr_444                    E..V....
 dnxhr_hqx                    E..V....
 dnxhr_hq                     E..V....
 dnxhr_sq                     E..V....
 dnxhr_lb                     E..V....

Basic minimal syntax would be

ffmpeg -i in.mp4 -c:v dnxhd -profile:v dnxhr_hq out.mov

The Avid codecs package has no interaction with ffmpeg.

[19-1-2017] At this time, the encoder does not support 444 or HQX profiles.

[4-2-2017] Now, it does.


Is it possible to automatically generate highlights from video?

Theoretically, sure, it is probably possible to devise a computer program that could recognize the ball entering the goal and cut video around it, however this would have to be custom computer vision code and not something that would be generally available to the public.

It probably isn't as simple as just a motion trigger either since it needs to be something just the right size moving.  It would also be exceptionally hard to tell a goal attempt apart from a goal, though perhaps you could have it watch the net for movement using security camera software or something related assuming that the net is otherwise pretty static (and depending on your angle).

Overall, I wouldn't expect the greatest of results from such a system though.  It sounds problematic at best, even if you can get it working in the first place.

If you can synchronize a clock with the start of the recording, your better bet may be to hit a button during the game to take note of the time each time a goal is made and then try feeding the list of times in to a scripting based video editor that can cut 15 seconds before the goal and a few seconds after from the video and put them all together.  It's probably less work to get configured and more reliable, but it still would be a fair bit of work to do.


When overwriting happens, usually old file is removed. So, new file size is around 0 bytes. Here nothing to rescue.

If you realized your mistake ASAP, in a few seconds, you can press RESET button. You will lost everything unsaved. Perhaps, even file system commit with new data, so old data will be here.

Otherwise, your file lost. You can try to recover file as any other deleted file (possible buy new disk, create sector copy, use any software like R-Studio), but since file here, with new content, this may not help. Try chance in specialized datarecovery company.

Yes, here exists ultimate solution. In theory, you can scan every sector of you hdd for AVI signatures (with AVI it easy possible) and read "RAW" frames from your disk directly. But here two problems:

I don't know good tools for this. I know only one tool, which "in house", written for "in house" usage: http://an-private.narod.ru/video/dvchanger/dvchanger.htm - it dedicated for DV video only. I found some other public available tools like https://www.remosoftware.com/dv-file-recovery, but it not tested by me and I can't suggets it.
Even if you file was in AVI, and you restored frames from your disk, frames may be mixed together due disk fragmentation. So you may get mixed your footages with other files. If you have very costly file, you can try to spend many hours in Premiere to recover it.

Sometimes it's easier to write a program for a specific case and equipment than to use ready-made utilities designed for general purposes. I wrote such a program for a dental camera and successfully restored the video


Is there an equivalent to Premiere's tilde key in DaVinci Resolve?

You can't expand any panel to full screen in Resolve 16 like you can in Premiere Pro.  You can expand the viewer to full screen with cmd/ctrl-F, and on the color page you can also get different viewer expansions with alt/opt-F and shift-F.
Beyond that, if a panel can be hidden, it's listed under the Workspace menu->Panels in Workspace, or by simply dimming its tab across the top of the screen. Not all panels can be hidden in Resolve.  In general, Resolve's UI is less customizable than Premiere.
BlackMagic's approach to UI design is very structured, and while it takes a period of adjustment for new users to become comfortable, it mitigates the need to hunt for shifting UI elements. "Where did I put that panel" doesn't happen.  Neither does "Where did I get Dave's Fave Layout" when your name is not Dave, but Dave shared a project with you.

You can save layout presets, under the Workspace->Layout Presets menu, and you can re-map keybindings to most commands in Resolve.  This, coupled with the fact that the positions of UI elements are consistently and predictably located make it possible to automate repetitive tasks easily with third-party macro software (e.g. autohotkey for Windows; Keyboard Maestro for Mac) which use mouse clicks in addition to keystrokes.
But DaVinci Resolve's secret killer feature is actually not one you'll find in its (oversized) manual.  It's BlackMagic's stellar support staff and developers.  If you have a reasonable feature suggestion or bug report, post it to their user forums.  They will evaluate it, and if it's a good idea, they will implement it, quickly.  The last issue I brought up wasn't even really something I considered a big deal, and there was already a workaround, but they fixed it in less than a month.  And they've implemented my suggestions on multiple occasions.
Something like the tilde key for full-screen windows has probably been brought up before, but if they see more demand than pushback for it, and as long as the feature doesn't infringe on another company's intellectual property, they'll do it.


525/60 digitized SD video according to Rec. 601 is indeed 720 pixels wide, 480 pixels high, including some blanking on the sides. Digital equivalent of 625/50 is 720x576. In both cases, frame aspect ratio is 4:3, this simply means that the pixels are not square. See https://en.wikipedia.org/wiki/D-1_(Sony)

To make matters more complex, only a subset of the frame has 4:3 proportions. I believe, only the 704x480 (for 525/60) and 704x576 (for 625/50) has 4:3 proportions. See discussion here: https://lurkertech.com/lg/video-systems/

So, 480 pixels are 10/11 in proportion, 576 pixels are 59/54 in proportion. Also see here: https://en.wikipedia.org/wiki/Pixel_aspect_ratio And do not forget, that both 480-line and 576-line formats can also be widescreen (16:9) yet having the same number of pixels per line! Plus, numbers like 59/54 are not easy to work with. All of this caused that for 576-line format pixel aspect ratio has been chosen as 12/11 for 4:3 screen aspect ratio, and as 16/11 for 16:9.

Square pixels became the norm starting from VGA video adapter I believe, and then from HD specs for 720-line and 1080-line video. By the way, there are some HD formats that record 1440x1080 or 960x720, yet having 16:9 frame aspect ratio, they also have non-square pixels. Square pixels are relatively recent development and should not be automatically expected.


How to quickly remove unnecessary sounds in FCPX?

There are 2 methods that might help with this.

Press the I and O keys to mark a range around the audio you want to fix. Then press CTRL+OPT+L and type a number value for the amount you want to the audio to drop (eg:-60db)
Make your keyframes, select them, then OPT+SHIFt+C to copy them, then OPT+SHIFT+V to paste them where you need them.

Method 1 is probably more flexible as you can customise the range if need be.


Windows software for recording multiple video/audio sources?

If it were me, I would try using a video recording interface with RCA connectors, as most TVs have an RCA audio/video output. Most of these connect via USB and come with some sort of software. For the video of the players, use a second software program and webcam/etc. to capture this. If you had a Mac, this could probably be sync'd in Final Cut Pro. I'm not familiar with all the software for Windows.

The main part I don't think you'll be able to accomplish (without expensive software) is capturing all of this in-sync with each device. This would require some sort of video-switcher software, similar to what TV stations use for live broadcasts. The method above is probably your cheapest route, if you can handle syncing it after the fact.


For the rolling shutter issue, you can check AE CS6 built in tool, Effect > Distort > Rolling Shutter Repair, if you haven't already. This basic tool is useful in some of the shuts but in more action packed footage (this is the case i think), you can try The Foundry's ROLLINGSHUTTER plug-in, which is more powerful. And there is a Virtualdub plugin, Deshaker, claimed to fix the rolling shutter artifacts, but i couldn't test it on my own, worth trying.

For the lens correction, there are built in stuff in AE CS6 (and probably in Premier Pro, i'm not sure though), Effect > Distort > Optics Compensation. Play around with the Field of View parameter along with the others. You'll have some loss in quality yet you may find the correct balance after some experimentation.

You can try first adding the rolling shutter fix, precomp the footage, then add the lens correction or vice versa.


What are some tips for shooting green/blue screen footage?

Jonas Hummelstrand has a great guide over on his blog - General Specialist that details out a bunch of tips for it (including descriptions and pictures), I'd recommend checking that out.

Ultimately the #1 key is lighting - you have to maintain a smooth and consistent lighting job on the backdrop so that the camera "sees" a consistent blue/green free from dark and light spots.  Not only does this make it easier to remove the background, but it means you can use a smaller "slice" of the color spectrum and thereby makes it less likely that you'll accidentally remove part of your foreground subject.

The #2 key is separating your foreground subject from the background (once again, to make the edge definition clear and easy to define).  You want to put at least a few feet between them and the screen (to reduce the amount of green/blue light reflected off the wall and onto them).  If you're using a greenscreen, it often helps to use an amber backlight for your subject (being the opposite of green means that amber cancels any bounced off green light).


How should I light two people teaching a dance video tutorial?

I've been in similar situations/venues in the past. It reads to me like you have little to no budget and no crew to speak of, since you are asking the question yourself which suggests that you are going to do the lighting yourself.

So, unless you have the budget to rent a proper yet smallish dance venue with already set up ceiling lights, with enough money left over to hire the services of a professional lighting technician to make those ceiling lights work for you on the day or of the shoot, I would suggest you don't really bother with getting lots of unwieldy lights, as (1) you're going to need a lot of them (or powerful ones) to do it properly/evenly, (2) you're going to be working in dance studios with probably low ceilings (not good for good lighting), and (3) you'll have little man-power to adjust the lights as you shoot, set up the gear, etc. (try not to over-extend yourself).

Still, here's what you should consider:

Make sure you get a space that's already well lit by nice-looking natural light. The light in your screen grabs looks fine to me, although I would draw the curtains seen in the background of the middle venue (too distracting because bright/overblown).
Start your shoot early to get as much natural light as possible over a long period.
Restrict the space that your dancers can cover: you're not going to bring huge lights but smallish ones, like three or four 650s. Whatever you bring (no kinos 'cause they're no good for large spaces), your lights won't probably be quite powerful enough to give your the output you need to light the dance space evenly (with bounce/diffusion, etc). So, again, restrict the space your dancers can cover to help you light a smaller area of the stage/space as evenly as you can ("evenly" doesn't mean flat).
Since you're not going to be able to bring a lot of lights nor be able to raise them high-enough to get a proper look, concentrate mainly on increasing the overall brightness levels of the room by bouncing light of off the ceiling/upper corners. Venue One, as seen in your screen grabs, looks good to me, thanks to its white ceiling. Avoid the space with yellow walls as your subjects will look like they have a jaundis!
If you still have time and energy to spare, give your subject some back rim light by blasting them from 3/4 back, either from one side of the stage or two sides. Use light or heavy diffusion, etc. to control it as you wish.
Make sure to keep your subjects far enough from these light sources (which blast them directly) to avoid their getting super hot as they get closer to the lights as they dance around.
Keep an eye on your lighting scheme color temp if you're mixing light sources (natural and artificial, etc): play with CTOs or CTBs until you get a proper look.
More importantly, AUDIO! I would actually make sure that your subjects are properly miked and recorded: bad audio will make your video(s) really feel amateurish. You can get away with quite a bit when it comes to lighting, not so much with bad audio.
So, hire the services of a good production audio person, or do it yourself by putting lavs on your two subjects and getting good levels throughout.
Note: dance studios with lots of heavy curtains covering the walls sound better: less audio reverb/bounce! Box-like rooms will sound like shit.
Also, I suggest putting tape over the soles of your dancers' shoes (or whatever you can do) to muffle their tap-tap sounds as much as possible.
Clothing: your subjects' outfits work well generally. Avoid white ('cause it's white!), and avoid black tops (if the background in black, of course).

Good luck.


Get effect to overcome image size [After Effects]

If you are applying the light wipe to an image which is smaller than your full comp size, then the light wipe effect will only fill the size of the image, not the full screen.

To overcome this, you could add a full screen solid behind your image, and pre comp the image and the solid.  Then add the light-wipe to the comp, not the individual images.

Alternatively, you could try putting an adjustment layer between your two images, and applying the light wipe to that.


Does My Business Model Break Youtube API TOS?

It is probably okay, see section 2 (bolding is mine):

The following commercial uses are permitted provided that You comply with all other terms and conditions of this Agreement:

the sale of an API Client

To get a definitive answer you should consult a professional legal counsel, so that the counseling that you get is backed by professional liability.


Null object to toggle volume in After Effects?

Add a Slider to your Null Object.
Alt-click on the stopwatch next to the one of the volume controls that you want to control.

This will open the Expressions box for the volume control, and a pick-whip icon will appear.

Drag from the pick-whip to the Slider in your Null.

Some code will appear in the Expressions box, something like:

temp = thisComp.layer("Null 1").effect("Slider Control")("Slider");
[temp, temp]

The numbers on the volume control will turn pink to indicate that they are being controlled by an expression.

Now move the slider on the null, and the volume should change on the audio track.

To do this to multiple audio tracks, just follow the same process.

Here is a screen shot to illustrate this:


How to add a "presenter's name" graphic to Camtasia that appears in from the right

The term you're looking for is 'lower third'. Here's a tutorial from the software publisher on how to do that.


How to work with R3D and RMD files? FFMPEG?

R3D files are essentially just a custom container that holds video encoded in JPEG2000 and PCM audio. Though ffmpeg only supports the RED container until version 3, not the newer version 4 (see this).

You can convert RED version 3 files the same way you would convert any other video with ffmpeg.
F.e. to h264 use the command below. Doesn't make much sense though to use h264 for further editing, you will have to use an intermediate codec and or container that your software supports:

ffmpeg -i input.r3d -vcodec libx264 -preset slow output.mp4

The usual way though is to use the free REDCINE-X tool provided by RED:
https://www.red.com/downloads?category=Software&release=final

It allows you to transcode your r3d files into pretty much any desirable format as long as its supported by V4W (Video for Windows, e.g. all codecs installed on your system). Or QuickTime on Mac.

Redcine is also the only useful way to do something with the RMD files.


From my experience this can typically occur when Premiere is having either a hard time loading a buffer for the audio, or you're putting too much strain on your computer memory.

I'd clear out the Premiere cache, which you can do by going to “Preferences > Memory.”

If it's an issue that occurs through different clips, something tells me it's to do with either the amount of memory Premiere needs to process the realtime feedback for audio, or the bitrate of the clips. If your bitrate is too high, it'll DEFINITELY cause some playback issues.


Merge multiple video files using ffmpeg by adding multiple compress options

All filtering should be performed in the same filtergraph. Each -filter_complex or -vf defines a different filtergraph. You can use

-filter_complex "[0:v] [1:v] [2:v] [3:v] [4:v] [5:v] [6:v] [7:v] [8:v]  [9:v]  [10:v] concat=n=11:v=1,scale=1280:720,setpts=0.20*PTS [v]"


Converting videos taken by D5100 for a Youtube upload

Amazingly, the best place to start with a question like this is Youtube. Believe it or not they have help file that explain the process with quite a bit of detail:
https://support.google.com/youtube/bin/answer.py?hl=en&answer=1722171&topic=2888648&ctx=topic

On Youtube itself many others have offered up video tutorials on how to do it:
Youtube.com search

I would take the recommendations that YouTube has on the help pages, and simply apply those settings to your favorite video software, it could be something like Adobe Premiere Elements which is a very common video editor, but many others exist.


Adding annotation to existing video file

Take a look at Blender or Lightworks (both free).
You can import footage and add text or shapes (simple one with Lightworks) to it.


Making background element out of a part of a video

You need to rotoscope every object in front of your "background". There is not simple solution, because AE cant tell the difference between you foreground and background. Even I can't tell, because people drop shadows on your "background", etc.

You can try to use rotobrush for that, but if you have there a lot of people, it will require a lot of work.


Formula / Calculate how much to slow video down to match audio?

(115bpm / 120 bpm) * 100 = 95.83% (approx, to 2 decimal places)

Speed change percentages are always confusing.

Final cut expresses speed changes as:

  If you change the speed to 50 percent, your clip becomes twice as long
  [...]
  If you change the speed to 200 percent, the clip becomes half as
  long

So if you go from 120 bpm to 115 (a slower tempo), you are looking for a longer clip, so your percentage should be lower than 100%.


How to match output parameters with input ones in Adobe Premiere?

The option you are talking about matches the export settings to the sequence settings, not to the source material. So my guess is that your sequence does not match your material. You can create a sequence that conforms your source clip by right-clicking on the clip in the project panel and selecting "New Sequence From Clip". Then the export should work as intended.

However, keep in mind that this will reencode your entire video, which will always result in quality loss. If you want to cut out a piece of your video while leaving the rest untouched, you could probably do that with ffmpeg.


How to prepare AVCHD on a PC for Mac use later?

Don't do anything to the files, Premiere Pro should be able to handle them. Just copy them to a USB drive and hand them off to your editor.

NEVER convert your video files prior to editing. You'll lose quality for no reason.

If the Mac won't open them, try another media player such as VLC media player. For a PC, I'd say you may need to install Quicktime as it comes with a codec that may be required, but on a Mac that should be preinstalled anyway. If that doesn't work, update your operating system. Or just try to import them to Premiere, if it doesn't work, update Premiere.


How can I preview with audio in After Effects and be able to pause / resume the preview?

To enable the audio playback, only way is to use the RAM-Preview. Press Numpad 0 or the associated |||> in the Preview Panel to start the preview rendering process:

Press Numpad 0 again to stop it
Press Numpad 0 twice to stop and playback the previously rendered (green) frames

In terms of correct audio playback:

Set the Frame Rate to the composition settings
Enable From Current Time option
Enable Sound Preview (6th button in the first row)

In order to facilitate the work:

Set the rendering resolution of the view to a lower value for e.g. to half or quarter
Limit the work area in your timeline, press B to set the start render point (Begin), press N to set the end point (End)
Enable Loop preview (7th button) to repeat the preview of the current work area

Note: As @Emir Dupovac mentioned, also check your waveform:

See this related answer: AE - Composition video file/layer missing audio


Premiere Pro - How to paste effects? (namely opacity)

If you need to copy opacity effect with keyframes, you should select keyframes and press CTRL+C, then select clip on timeline and move playhead to time where you want to put first keyframe, then select effect controls window and click CTRL+V to paste. That's all.

In such way you can copy keyframes from one clip to another.

If you want to copy keyframes from one clip to a lot of other clips, you can create preset in such way:


I am not able to take video with my SD card

There are two possible problems, first is that your camera does not appear to have SDXC support.  32GB is the limit of the SD and SDHC file system used on lower capacity memory cards.  To move to 64GB, you have to move to exFat which your camera may not support, so the card may simply be too big.

It is also possible the card is simply too slow to support your chosen resolution and quality level.  Have you tried stepping down the quality (to IBP or less than 1080p)?  The Ultra line of SanDisk cards is one of their slowest lines and $60 for a 64GB card is not expensive, it is dirt cheap.  To give you an idea, the SanDisk Pro Extreme SD card that I use (which is still slower than my compact flash card I use) was $150 for a 64GB card that handles 1080p video at All I frame storage.

Update: After some more reading of the manual, it appears the problem is the card size.  I see your camera doesn't even support 1080p video at all and 720p should be fine on an Ultra card.  It simply doesn't support exFat, so you will need to limit yourself to a SDHC card of no more than 32GB.  It might be worth doing some more digging on that too as there are SDHC cards listed for your camera, but none in the 32GB range (but that may simply be that there weren't any available when it was made.)  I would verify 32GB compatibility before buying a 32gb card since 16GB is the biggest listed in the manual.


How to move clips without loosing transitions?

The "Slide Tool" tool makes it possible to move a single clip without loosing the transition connected to another clip.


Batch conversion into a new folder with ffmpeg

The accepted answer in the question you're referring to uses additional unnecessary processes, legacy code, and doesn't prevent globbing or word splitting.

See the second answer which is shorter, simpler, and more efficient:

for f in *.mp4; do ffmpeg -i "$f" <additional options> "encoded/${f%.*}.mp4"; done

Secondly, don't use fancy quotes which will cause errors, so instead of “$varible” use "$variable".


libx265 NUMA pool configuration misleading

As the excerpt below says,

  A thread pool dedicated to a given NUMA node is enabled only when the
  number of threads to be created on that NUMA node is explicitly
  mentioned in that corresponding position

"+,-,+"  --> no numerals stated, hence a single pool.

"8,+,+,+" --> numeral for node 0, hence that's one pool. The other nodes have no numerals, hence any threads spawned there are managed within a consolidated (2nd) pool.

No experience with NUMA, just parsing the quoted doc.


False copyright claims by "Orchard Music"

Ok, this is quite a complicated problem actually, and depending on the specific situation, the answer might vary. So I'll break this down in a couple of subsections.
CC licences and unauthorized distribution
Creative Commons are a set of licences that allow creators to distribute their original content (e.g. music) using liberal licences under easy to understand terms. However, in order to do so, the uploader needs to hold the rights to the music (usually this means they are the creator). If they don't, they have no right to grant any permissions regarding the use of that music. It's your responsibility to check if they do have those rights.
Excerpt from my answer here:

Remember that just because someone uploads music to a website and claims it's free-to-use, it doesn't mean he actually has the right to do so or the authority to grant you any rights to it. And if you use a copyrighted piece of music in your project without knowing any better, you can stil be held responsible even if you downloaded it from a website that claimed it was free. Always check if the website you are downloading from is legit and if the uploaders actually have to rights to the music (in most cases, that means they made it themselves).

In short, just because someone uploads a Hannah Montana album to some website and puts a CC icon next to it, you still can't use Best of Both Worlds in your video. And if you do, you can't rely on your claim that you got it from that site, because the uploader didn't hold the rights to that music in the first place and it would've been your responsibility to check if they do.
If it's music from a rather unknown author and there were no signs that the original source isn't legit, you might not be held responsible for the 'damage' (claimed by the copyright holder, whether that damage actually exists is a rather philosophical question) caused by your usage of the music. However, even in that case, you'd have to take your video down. So there's no winning in a situation like that.
tl;dr: Always make sure that uploader of whatever music you want to use actually made that music.
In your case, the Soundcloud account looks to be legit, so let's proceed.
CC licenses and retractability
This is only tangetially related to your specific problem, but it's actually something that I think is quite relevant to false copyright claims regarding CC licenced work. All CC licences contain this condition:

The licensor cannot revoke these freedoms as long as you follow the license terms.

What this means is as long as you uphold the terms of the licence, the uploader can't retract the permissions granted by the CC licence. Of course that doesn't mean he has to continue distribution his works indefinetely. But if a music creator at some point decides to stop distributing his work under a CC licence, this doesn't affect any work using his music (e.g. your YouTube video) that was created before that time.
So, assuming you made sure the uploader of the music holds the right to it and follow the licence terms (e.g. proper attribution), your video doesn't infringe any copyright and you are right to dispute such a claim.
(Note: If an artist at some point stops distributing his music under a CC licence, from that point onwards you can't rightfully publish any new work using his music, even if you downloaded it while it was still CC licenced. The non-retractibility only affects works published while the music was being distributed under a CC licence.)
However, being right isn't all there is to it. There's a saying in German:

Recht haben und Recht bekommen sind zwei Paar Schuhe.

Roughly translated: Being right and being proven right are two different things. That's where YouTube's ID system and false copyright claims come into play.
YouTube's ID system

"In the beginning the YouTube ID system was created. This has made a lot of people very angry and been widely regarded as a bad move"

YouTube has a system in place that automatically checks for copyrighted music in uploaded videos and places copyright claims accordingly. The copyright holder of that music (according to YouTube's database) then gets notified and can decide what to do with it; for example, they can have the video taken down, or they can decide to leave it up but receive a portion of this video's ad proceeds. They can also decide on a default action, and that's a big part of the problem that made many people very angry.
In 2013 especially there was much trouble regarding this system. The problem was, the automated ID system was terrible to begin with and would often attribute music wrongly. There were also many scammers that would claim copyright for music that wasn't theirs. The problem is that in cases like this, YouTube favors the copyright holder. So instead of having the person who claims a copyright infringement provide them with proof, the video creator's have to dispute a claim and provide prove that they didn't infringe any copyrights. This usually took a couple of weeks and in the meantime, the person to claim the copyright infringement got all the proceeds from that video.
This system has since been refined and the uproar died down, but you still hear stories like yours occassionaly. When in doubt, YouTube still favors the copyright claimer over the video creator.
The Orchard Group
I hadn't heard of the Orchard Group before, but I've looked through the links you included in your question and did some additional research. As you already said, you are not the first creator to have problems with false copyright claims. On the forums, many people are quick to call them scam artists. But I'm not sure about that. There are also some stories about people that contacted them and got their false copyright claim resolved quickly. I believe the root of the problem might be this:

The Orchard's YouTube multi-channel network has more than 1,000 channels across the globe and uses technology, built in-house, called B.A.C.O.N. (Bulk Automated Claiming on The Orchard Network) to crawl, claim and track YouTube videos to monetize for their clients. It was ranked 7th in the U.S. in July 2014.

Source: Wikipedia
However, according to this source, the Orchard Music isn't unwilling to forfeit wrongly submitted copyright claims:

YouTube users have expressed concerns about The Orchard claiming copyright ownership of music used in user-generated content that may or may not belong to them. According to an article by The Orchard on their Daily Rind blog, if audio is matched to a particular copyright owner via YouTube's content identification system, then one or more links will be placed under the video in order to help promote the copyright owner's music, with the video remaining available. The article states that erroneous claims are removed by The Orchard Team after review upon email communication with their dispute department.
In this context, The Orchard has been criticized by YouTube users for claiming content that is not theirs or in some cases, content that did not exist within the video at all. In a blog post on The Daily Rind, The Orchard explains that this is due to YouTube's automated Content ID matching and outlines steps for resolving this scenario.

So, you got two automated systems that can both screw up and have been shown to do so often. Not an ideal situation for content creators. If you get caught in such an automated system, the solution is almost always to contact the people responsible for it. Contact the Orchard Group and possibly also contact the original artist of the music. If they are indeed not trying to scam anyone, they will be willing to help you. If the Orchard Group doesn't reply, public shaming on Twitter oftentimes helps you get in touch with an actual person, not just with an email autoresponder.
If they actually are scammers or plainly refuse to forfeit their copyright claim, you will have to contact YouTube to get it resolved. So ...
Your questions

How is it possible that Orchard Music can claim ownership of a Creative Commons music production?

As mentioned, this is mostly done by automated systems that are prone to misfires, especially if larger distribution/collection companies are involved. Also, you can claim anything, that doesn't mean you actually have any lawful grounds on which your claim is based. I can claim that I be crowned High King of the Universe, but nobody will have to call me Your Majesty. And if I sue them, I'm unlikely to win that case.

Why do I need a publishing license to a Creative Commons music production?

You don't. The CC licence gives you the right to publish your video if you follow the terms laid out in the licence, you don't need to pay any additional licence fees or royalties. However, a human error is also possible.
For example, maybe the artist is represented by the Orchard Group and never intended to publish their work under a CC licence. Maybe they just forgot to change that setting while uploading their music to Soundcloud. I'm not sure about Soundcloud, but if you for example upload something to Vimeo, a CC-BY licence is applied by default, and you have to go into a submenu of the settings to change that. I think that is a terrible implementation, but that's how it is.
Even if that case, you would probably be within your rights to invoke the licence terms the author published his music under, but it might not be feasible or realistic to do so and see your claim through.

Should I dispute the claim for the second time?

That is your decision. Before you do anything, check if you followed all the licence terms, the legitimacy of your music source and everything else mentioned in this post. It might also be better to contact the Orchard Group or the artist directly to see if you can't get the issue resolved without involving YouTube as a third party. Though a lawyer would probably tell you that contacting them is the worst thing to do if you plan to follow this up with a lawsuit.
Just remember, being right doesn't mean YouTube will take your side. And if they don't, there's little you can do besides suing, which might not be feasible for you.

Disclaimer: I'm not actually sure I answered your question after all that text. I'm sure I forgot something, but there's so many important factors involved, it's hard to put everything into one answer. Feel free to ask if I forgot anything, I'll be happy to edit my answer if I can. Also note that none of this constitutes legal advice. It's rather a description of the current situation regarding YouTube's copyright claims systes and some pointers as to what you can reasonably do to get this problem resolved. Your theoretical (lawful and moral) rights and responsibilites might actually differ from what you can reasonably enforce.


My Canon Powershot SX40 stops recording regularly and predictably.

The squares in a row on the right represent the buffer memory of your camera.
When you are recording video the data goes roughly as follows:

Sensor -> Buffer memory -> Memory card

When the last square turns red it means the buffer is full. This is caused by the fact that the buffer memory could not move it's contents to the memory card fast enough. A faster memory card would allow the buffer to load it's contents in time and you shouldn't see the red square anymore.

Baseline is: get a faster memory card.


Searching for video converter that maintains folder structure

Most decent encoders with watch folder support have an option to automatically encode to the same folder structure that the source came from.  I'd check the listing of any software you are looking at to see if it supports it or try a demonstration copy.  I know that Adobe Media Encoder does.

Beyond that level of detail, this is a product recommendation question which is off topic since software may or may not be available tomorrow and the options for video conversion software change frequently.


I don't have lot of experience in working with video in Linux, however, there is Blender, which is capable with video editing, and it also can morph still images and meshes. And of course more complex 3D objects.

Maybe you can achieve your goal, by combining those techniques.


How to do a better and easier roll transition in Kdenlive

I think you should try the other transitions again
Please do not be absolutist
I also enjoy the transition roll
But
Do a quick Google search for smooth transitions. Maybe it's right for you
Good luck


ffmpeg concatenation introduces video stutter but does not affect audio

For some reason I think this is avoided when using ffmpeg's concat PROTOCOL (ffmpeg -i "concat:...") rather than its concat DEMUXER (ffmpeg -f concat -i mylist.txt).  Oddly, it's also slightly more convenient since using the demuxer requires me to create the text file with the file names in it while with the protocol I can just specify them on the command line, eg: ffmpeg -i "concat:00001.MTS|00002.MTS|00003.MTS" -c copy output.mts

I'll need to confirm this later, I'm at the wrong computer but something brought the question to my attention so I decided to update it with new information.


Most screen capture applications are pulling video from the video card down to main memory to compress it and write it to disk. Most video games are uploading textures and geometry to the video card to display it to you. It's possible to get into a situation where more memory is needed on the card to run the game and record the video than you have available. That's usually when you see frames dropping. Depending on the game, it might happen when more characters or scenery is visible (such as when viewing a scene from high up, and it's all in frame). The memory on the card is limited, and the ability to move data around in the computer is also limited. It sounds like you're hitting those limits.


Container format requires global headers

This issue was fixed with commit 955b818:

commit 955b818cf947473ec94a3fe8aa7f408b119fbbc9
Author: Clément Bœsch <clement@stupeflix.com>
Date:   Thu Sep 1 16:48:45 2016 +0200

    ffmpeg: switch to codecpar

You can suppress the warning on older version like so:

ffmpeg -i Miaow-02-Hidden.m4a -c copy -flags global_header outfile.m4a

Example


ffmpeg: Create a black background video from audio, for Youtube upload

Alternatively you can have ffmpeg generate the black video with the color source filter instead of making an image:

ffmpeg -f lavfi -i color=c=black:s=1280x720:r=5 -i audio.mp3 -crf 0 -c:a copy -shortest output.mp4

Since it is just black video this is one case with lossless mode (-crf 0) will have a smaller file size than the default lossy mode.
The resulting file may not play in your player or device, but it will on YouTube.


Is low-framerate video recording possible on the D7100 without miniature effect?

No.

The miniature effect is the only creative mode that also allows movie creation. It suffers from performance "issues" giving it's unique time lapse like feel.


Using super resolution to improve video quality

Yes, there is a method using AI to upscale images:

if you convert your footage into an image sequence using ffmpeg, you could run every frame through such upscaling.


What is Frame Doubling in Action Cameras?

The term "frame doubling" is occasionally used to describe the result of animators who "shoot on twos".  Namely, when an animator draws only every other image for a given frame rate, the image is displayed twice before the next image is displayed.  That "frame doubling" is an observable property of the animation, but it is not the key idea.

The key idea is that frame rates can be subdivided (shot on ones, twos, threes, or even fours) and the look and effect of each can be appropriate for a given instant.  Generally, lead animators generate key frames and junior animators (or computers) generate the in-between frames.  Shooting on ones requires generating twice as many in-between images as shooting on twos.  But it also creates a smoothness that may or may not better serve the aesthetic of the animation.  Nick Park's classic Wallace and Grommit animations look "right" because of frame doubling.  Pixar's Toy Story films look "right" because they shoot on the ones (and integrate motion blur on every frame to look as if shot on a cinema camera).

I would argue that a camera that shoots at 1/15th of a second and then doubles those frames for a 30fps playback will create a highly stylized look that combines (in a "wrong" way) the motion blur one would expect from shooting on the ones with the pacing of shooting on the twos.  As Blues music teaches, the wrong note at the right time could be the right note.  But generally, animation shot on twos rarely integrates motion blur as such would be "too obvious".  So if going for a frame doubling effect, one should use a small shutter angle, like 30 or 45 degrees, not 180 or 360, when shooting 15 fps.


Do people fundraise to help someone buy a camera?

I remember when I was in high school I used to borrow their Canon 600D to use over the weekends. I loved it, but it was upsetting to have to return it every Monday. Like you, I couldn't afford to buy one at the time.

It wasn't until I got a casual retail job that was able to buy my first camera.

Now I'm a little older and have a steady(ish) income, I'm able to lease more expensive cameras and pay them off over time.

I'd argue that if you're after an individual/organisation to offer you a grant, you'd need a solid portfolio to convince them to do so. If no-one seems interested, then I'm afraid you'll need to wait and buy one yourself.

It doesn't need to be a $1600 camera right now, it can be an older second-hand one, because ultimately, if you have a good story, it doesn't matter what camera you use to tell it.