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View Full Version : Why .vp8 instead of .x264 for Web Access encodes



smitbret
05-12-2016, 10:52 AM
The default encoder for the Web Access profile tends to be .vp8 rather than .x264. Is there a reason for that? I think by now it is fairly accepted that .vp8 gives inferior results and is more CPU intensive than .x264 and my personal experience from Beta testing through Final Release seems to support that.

Otherwise, Mezzmo 5 is a clear winner. You should be proud.

Paul
05-12-2016, 11:56 AM
The h.264 video codec is only officially supported in the MPEG-4 container for HTML5. MPEG-4 requires a MOOV atom, which contains the index of the audio and video channels within the MPEG-4 file. This atom is only written into the MPEG-4 file at the completion of encoding, so this means that transcoding on-the-fly is not possible in this scenario (i.e. a video player needs to read the MOOV atom first up when trying to decode and play the MPEG-4 file).

Whereas, the VP8 video codec is officially supported by the WEBM container for HTML5, and it does not have this MPEG-4 index/atom requirement - meaning transcoding on-the-fly is possible. Regarding the quality & CPU usage of the resulting videos, we can look into this further by tweaking our VP8 encoding settings.

Glad you like Mezzmo v5.0 so far :).