  Video shared over the internet is commonly referred to as user generated
content (UGC). UGC video may have low quality due to various factors including
previous compression. UGC video is uploaded by users, and then it is re-encoded
to be made available at various levels of quality. In a traditional video
coding pipeline the encoder parameters are optimized to minimize a
rate-distortion criterion, but when the input signal has low quality, this
results in sub-optimal coding parameters optimized to preserve undesirable
artifacts. In this paper we formulate the UGC compression problem as that of
compression of a noisy/corrupted source. The noisy source coding theorem
reveals that an optimal UGC compression system is comprised of optimal
denoising of the UGC signal, followed by compression of the denoised signal.
Since optimal denoising is unattainable and users may be against modification
of their content, we propose encoding the UGC signal, and using denoised
references only to compute distortion, so the encoding process can be guided
towards perceptually better solutions. We demonstrate the effectiveness of the
proposed strategy for JPEG compression of UGC images and videos.
