[FFmpeg-devel] Why does vp56_init() sets avctx->width and avctx->height to 0?

Baptiste Coudurier baptiste.coudurier
Sat Aug 30 23:58:21 CEST 2008

Hi Aurelien,

Aurelien Jacobs wrote:
> Stefano Sabatini wrote:
>> Hi,
>> this causes a bug both in ffprobe (prints widht=size=0) and causes a
>> division by 0 exception in libavfilter/vf_scale when it tryies to the
>> parameters for the filter.
>> What's the point into setting those values to 0?
> The point is that the actual frame width and height are not known
> at this point. They only get known after parsing the header of the
> first key frame.
> And also don't forget that those value may change at every key frame.
> The width/height is not an intrinsic property of a video stream, it's
> a property of each individual frames.

Any reason to _set_ them to 0 instead of leaving them "as is" and set
them during decoding like every other decoder do ? I'd prefer the
latter. I know this has already been discussed before.

Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
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