[FFmpeg-devel] [PATCH 1/3] lavf/riffenc: Improve spec compliance

[Mats Peterson]

Mats Peterson <matsp888-at-yahoo.com at ffmpeg.org> skrev: (12 mars 2016 12:14:03 CET)
>On 03/12/2016 12:08 PM, Mats Peterson wrote:
>> On 03/12/2016 11:53 AM, Mats Peterson wrote:
>>> On 03/12/2016 11:48 AM, Mats Peterson wrote:
>>>> On 03/12/2016 11:43 AM, Mats Peterson wrote:
>>>>>>>>> why do you think they are written by libavformat ?
>>>>>>>>>
>>>>>>>>> i see:
>>>>>>>>> "C:\PROGRAM FILES\ASUS\ASUS LIVE\ASUSLIVE.EXE -AVICAP32- ASUS
>Video
>>>>>>>>> Capture Driver, Version:  3.8.2.2"
>>>>>>>>>
>>>>>>>>> in asv2_320x240_3.avi
>>>>>>>>>
>>>>>>>>>
>>>>>
>>>>> Regarding asv1/asv2, they do use 48 in biSize, but since there is
>no
>>>>> official documentation for these codecs that explicitly mentions
>that
>>>>> biSize should be 48 (which breaks the specs), it's plain wrong to
>use
>>>>> anything else than 40.
>>>>>
>>>>
>>>> Furthermore, any "global headers" in *any* codec have nothing to do
>with
>>>> the BITMAPINFOHEADER. They aren't connected in any way. The size of
>the
>>>> BITMAPINFOHEADER is 40, so biSize should always be 40, since it
>defines
>>>> the size of the BITMAPINFOHEADER, not the size of the
>BITMAPINFOHEADER +
>>>> extra data.
>>>>
>>>> Mats
>>>>
>>>
>>> If it wasn't for the braindead specification of HuffYUV with its own
>>> BITMAPINFOHEADER variant, this would be a piece of cake. Always use
>40
>>> in biSize.
>>>
>>> Mats
>>>
>>> _______________________________________________
>>
>> I vote for using huffyuv and ffvhuff (since it's a variant of
>huffyuv)
>> as the only exceptions to using 40 bytes in biSize, regardless of any
>> non-conformant existing or future stuff.
>>
>
>If the authors of future specs should happen to think that biSize
>should 
>be anything else than 40, we'd better tell them the facts.
>
>Mats
>
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Perhaps you can use my latest 2-part patch set that includes asv1 and asv2 in the "exception list", but thaf's it. No more entries should ever need to be added to this list.

Mats
-- 
Mats Peterson
http://matsp888.no-ip.org/~mats/