[MPlayer-users] Produce 422 format pixels with mencoder for mpeg4-encoding

[Tom Evans]

On Tue, Dec 10, 2013 at 1:27 PM, James Board <jpboard2 at yahoo.com> wrote:
>>Which MPEG-4 spec? You get plenty to choose from....
>
>>
>>I don't think MPEG-4 Part 2 (divx, Nero digital, xvid etc) supports
>>it, at least not in any commonly used profile. MPEG-4 Part 12
>>(AVC/H264) definitely does.
> So does Carl and Reimar are implying that MPEG4 doesn't support YUV422
> pixels, while Tom says that MPEG4 does.  What is the answer?

You need to stop saying "MPEG-4" like it is one thing - it is one name
for a whole collection of related standards, codecs and encoders.

MPEG-4 Part 2 is a standard for encoding video. The standard has a
bunch of profiles which determine the resolutions, bitrate, features
and color-space for the profile. Several encoders produce content that
conforms to one of the MPEG-4 Part 2 profiles - examples are xvid,
divx, nero digital and ffmpeg's "mpeg4" encoder. Not all encoders
support all the profiles.

I don't want to speak for Carl and Reimar, perhaps they are saying the
"mpeg4" encoder that mencoder exposes does not support YUV422. This
does not mean that MPEG-4 (the spec) does not support YUV422, nor does
it mean that MPEG-4 Part 2 does not support YUV422, just that the
profiles this encoder supports do not.

MPEG-4 Part 10 is a different video codec standard, also known as
H264. Like Part 2, H264 supports many profiles. Again, only some of
the profiles will support 422 content, the vast majority do not.

>
> If I capture Video in YUV422 format, does it make sense to try to
> use YUV422 pixels for all of the steps (Inverse telecine, editing, and
> conversion to MPEG4)?
>
> Or if it's impossible to create MPEG4 with YUV422 pixels, does it make
> more sense to convert to YUV420 pixels right away?
>
> Does mplayer play MPEG4 files with YUV422 format?

Most likely.

Cheers

Tom