[FFmpeg-devel] [RFC] Private streams in MPEG PS

Baptiste Coudurier baptiste.coudurier
Wed May 27 22:04:40 CEST 2009


On 5/27/2009 12:52 PM, Jai Menon wrote:
> On Wed, May 27, 2009 at 6:22 PM, Baptiste Coudurier
> <baptiste.coudurier at gmail.com> wrote:
>> Hi,
>>
>> On 5/27/2009 11:00 AM, Jai Menon wrote:
>>> Hi,
>>>
>>> I'm becoming increasingly suspicious of this check in lavf/mpeg.c:370 -
>>>
>>>   4093        mru     if (startcode == PRIVATE_STREAM_1 &&
>>> !m->psm_es_type[startcode & 0xff]) {
>>>
>>>              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>>
>>> Looking at issue 1122 and 725 on roundup,  I'm inclined to believe
>>> that a lot of files out there don't have a program stream map (which I
>>> didn't back when issue 725 was reported). Removing this check actually
>>> would solve both 1122 and 725 without the need for the fix commited in
>>> r17150.
>> Humm, pes_es_type should be init to 0 anyway, if file have no program
>> stream map. Isn't the problem that psm_es_type is wrongly set ?
> 
> PSM ES type is set to 0x81 which is correct for both ac3 tracks. The
> problem is that es_id (which should be unique by current demuxer
> design) is 0x1bd. The substream ids are 0x80 and 0x81 and imho we
> should consider those as part of the stream id.
> 

Humm, es_id is a byte so it cannot be 0x1bd ?

-- 
Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
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