[FFmpeg-devel] [PATCH 1/3] lavu/frame: add av_frame_check_align().

[Hendrik Leppkes]

On Thu, May 18, 2017 at 10:44 AM, Nicolas George <george at nsup.org> wrote:
> Le nonidi 29 floréal, an CCXXV, Hendrik Leppkes a écrit :
>> I wonder if there should be an exception in here somewhere for
>> hardware pixelformats, there is no reason to assume the hardware
>> pointers passed in AVFrame would be aligned, and aligning them would
>> cause all sorts of crashes.
>> Best case from an API standpoint would be if av_frame_check_align can
>> just claim hardware frames are aligned, so users don't have to
>> replicate that check.
>
> Possible, but I think setting the correct value for alignment is the
> best way of dealing with this kind of issue.
>

I think its a saner choice to design the API to try to avoid instant
heap corruption, instead of hoping every case sets the alignment
properly in all cases.
A single if condition shouldn't be too much trouble, we already flag
hardware pixel formats as such in the pixdesc to identify them.

- Hendrik