[MPlayer-dev-eng] vo_mpegpes_t->data format

[Nikolaj Fogh]

It's a slice layer decoder, so I need to extract some information from 
the picture header myself and pass it to the driver.

Right now I'm trying to print the data I get as binary patterns, but it 
doesn't match anything in the mpeg1/2 standard specification.


When I try to dump the first 7 bytes of data i get when playing a DVD I get:

00000000 00000001 00000000 00000000 00000000 00000000 10000000

or

10110011 00000001 00000000 00000000 00010110 00010110 00010010

the first 4 bytes looks a bit like some start codes, just "reversed"
picture start code 00000000 00000000 00000001 00000000
sequence header code 00000000 00000000 00000001 10110011

Arpi wrote:
> Hi,
> 
> 
>>I'm trying to implement a new vo_??.c "driver" for mplayer, so it can 
>>use VIA's cle266 h/w mpeg2 decoder. But i need some information about 
>>the data format given to me in the draw_frame() function. I use 
>>vo_dxr3.c as a template.
>>
>>Just as with dxr3 i get mpegpes, but after some time searching the web 
>>and printing bit patterns, i've given up. I even tried the mplayer IRC 
>>channel, but in vain. So if anyone knows about the data format i'd be 
>>very pleased to get some info.
>>
>>static uint32_t draw_frame(uint8_t * src[])
>>{
>>         vo_mpegpes_t *p = (vo_mpegpes_t *) src[0];
>>
>>src[] is a vo_mpegpes_t type alright, but the problem is 
>>vo_mpegpes_t.data in the struct.
> 
> 
> it contains a single video frame in mpeg ES (elementary stream) format.
> see mpeg 1/2 standard documents for the actual bitstream syntax.
> it is supposed to be sent as-is to the hardware decoder.
> 
> if your hardware is not capable to receive mpeg-es stream (nor mpeg-ps or
> -ts) then it's not an hardware mpeg2 decoder just some kind of mpeg
> acceleration (like XvMC for hardware accelerated idct/mc).
> 
> afaik the via boards doesnt have real decoder, just xvmc-capable s3 vga chip.
> 
> 
> A'rpi / Astral & ESP-team
> 
> --
> Developer of MPlayer G2, the Movie Framework for all - http://www.MPlayerHQ.hu
> 
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