Post subject: x264, YUV444, and RGB
sgrunt
He/Him
Emulator Coder
Joined: 10/28/2007
Posts: 1360
Location: The dark horror in the back of your mind
One of x264's developers is busily working on implementing the YUV444 colour space into x264, and relatively recently a third party has put together a patch to get it to work with RGB colour spaces as well. The most recent releases of ffmpeg support decoding YUV444 h.264, so programs that employ it (VLC, ffdshow, etc.) will probably, in the near future, be built to support it as well, which would allow us to consider deploying encodes in that colour space on a wider scale. I don't believe this is presently the case for RGB colour spaces, and I'm not aware of any efforts to get those implemented into ffmpeg, so looking at RGB would be a while off. In the meantime, I'm encouraging encoders to experiment with using YUV444 and see if they get better results (in terms of visual quality vs. disk space used) when making use of it. --- EDIT: YUV444 and RGB support has landed in x264's trunk. Presumably builds of this will be available soon, for all you Windows types. :)
Lex
Joined: 6/25/2007
Posts: 732
Location: Vancouver, British Columbia, Canada
This is awesome. Also, I'm posting this mainly to bump this thread because Grunt's edit doesn't do so (for those who weren't in #tasvideos at the time TVA announced it). Dark_Shikari has worked hard on this. Thanks, Dark_Shikari! He can be found in #x264dev on freenode for questions and compression test result reports. He's an advocate of questions. Several other codec developers/experts idle there also. Compression tests are always welcome. The x264 command line argument for 4:4:4 is "--output-csp i444". The x264 command line argument for RGB is "--output-csp rgb". My 4:4:4 test command line is
x264 --preset placebo --qp 0 --qpmax 0 --threads 4 --fullrange on --output-csp i444 --output "B:\media\video\capture\lexencode.264" "B:\media\video\capture\lexencode.avs"
"--fullrange on" is not necessary for RGB, as fullrange defaults to "on" with RGB. Edit: As of this edit, Dark_Shikari is also in #tasvideos.
Joined: 11/4/2007
Posts: 1772
Location: Australia, Victoria
If I wasn't currently stuck in South Australia, I'd be experimenting with this already.
Banned User
Joined: 3/10/2004
Posts: 7698
Location: Finland
Flygon wrote:
If I wasn't currently stuck in South Australia, I'd be experimenting with this already.
Damn those Australians!