VP8 - Comparison With H.264

Comparison With H.264

While H.264/MPEG-4 AVC contains patented technology and requires licenses from patent holders and limited royalties for hardware, Google has irrevocably released all of the VP8 patents it owns under a royalty-free public license.

According to a comparison of VP8 (encoded with the initial release of libvpx) and H.264 conducted by StreamingMedia, it was concluded that "H.264 may have a slight quality advantage, but it's not commercially relevant" and that "Even watching side-by-side (which no viewer ever does), very few viewers could tell the difference". They also stated that "H.264 has an implementation advantage, not a technology advantage."

Google's claims that VP8 offers the "highest quality real-time video delivery" and Libvpx includes a mode where the maximum CPU resources possible will be used while still keeping the encoding speed almost exactly equivalent to the playback speed (realtime), keeping the quality as high as possible without lag. On the other hand a review conducted by streamingmedia.com in May 2010 concluded that H.264 offers slightly better quality than VP8.

In September 2010 Jason Garrett-Glaser, a developer of the x264 encoder, gave several points of criticism for VP8, claiming that its specification was incomplete, and the performance of the encoder's deblocking filter was inferior to x264 in some areas. As a specification, VP8 should be a bit better than H.264 Baseline Profile and Microsoft's VC-1. Encoding is somewhere between Xvid and VC-1. Decoding is slower than FFmpeg’s H.264. Not much can be done about it because of similarities with H.264. The room for improvement is small because VP8 as a whole is similar in complexity to H.264. Compression-wise VP8 is definitely better than Theora and Dirac. The VP8 interface lack features and is buggy. The specification is not fully defined and could be considered incomplete. Because much of it is copy-pasted C code. And because the source is the specification any bugs will also be defined as something that has to be implemented to be in compliance. In the end Google has choosen Matroska and Vorbis for its proposal to HTML5. In regard to patent issues, VP8 has copied too much from H.264 for comfort and courts, not Google is the judge. If it can stand up it’s a big upgrade for patent-free video formats.