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View Full Version : How to convert color to RGB18 or RGB16 for mobile phones using AviSynth


Kay19
2nd June 2008, 15:32
Hello!

Does somebody know how I can convert a Video with 16 millions of colors to 262.000 colors?

I have got to convert a video for a mobile phone using XviD
or DivX and the mobiles' LCD has only 262.000 colors and
in another forum I have heard, that this color mode is
called RGB18... Now my question:

How can I convert a video to RGB16 or RGB18 or generally
to 262.000 colors...

Maybe using a script???
I know that VirtualDub offers 16bit,
but is there any alternative, because
When I encode the video in an old version of Quicktime 6.0,
the mobile video runs perfectly and shows no pixels
or artifacts/errors in dark areas, probably because
the encoder encodes to 16/18bit colors, but the
sound and picture looks bad, compared to XviD...
That's the problem...
I have encoded a video using XviD with 500kbps 176x144 (was stuttering alot but the picture was perfect, except in dark areas where
errors appear... And I have read that these LCDs of SonyEricsson are not able to display that colors and that this would be the
reason of why the errors appear only in dark areas)...
Probably generally a problem of older LCDs.

Or is there any way to make ffmpeg encode that video to 262.000 colors by using some specific commandline???
Can somebody help please???

Thank You!!!

Wilbert
2nd June 2008, 16:18
Hello!

Does somebody know how I can convert a Video with 16 millions of colors to 262.000 colors?

I have got to convert a video for a mobile phone using XviD
or DivX and the mobiles' LCD has only 262.000 colors and
in another forum I have heard, that this color mode is
called RGB18... Now my question:

How can I convert a video to RGB16 or RGB18 or generally
to 262.000 colors...

Maybe using a script???
AviSynth doesn't support RGB18. Sorry, i have no idea how this can be done. DivX/Xvid doesn't even support RGB18 (or any other RGB format).

GodofaGap
2nd June 2008, 16:41
No conversion should be required as MPEG4 ASP uses 8 bit 4:2:0 internally anyway, regardless of what format you feed it. What you need is a decoder that supports RGB18 output on your mobile.

Kay19
3rd June 2008, 23:48
@GodofaGap: Some specs say that it should already even only support RGB18??? Don't know whether that's true!?

@Wilbert & GodofaGap: Thanks for your help!!!