[FFmpeg-devel] [PATCH] snow: remove strange av_assert2

Andreas Cadhalpun andreas.cadhalpun at googlemail.com
Sun Jul 5 21:11:44 CEST 2015

On 03.07.2015 01:04, Michael Niedermayer wrote:
> On Fri, Jul 03, 2015 at 12:31:31AM +0200, Andreas Cadhalpun wrote:
>> It asserts that the frame linesize is larger than 37, but it can be
>> smaller and decoding such frames works. Thus it is unclear what this
>> assert is good for.
> i think it was due to the layout of some temporary /scratch buffer
> maybe in the emulated_edge_mc() call in ff_snow_pred_block() but
> iam not sure

I couldn't find a problem with the layout of the tmp/scratchbuf buffer
for small strides.

> as stride becomes too small its no longer possible to store some elements
> that is when they are larger

Can you explain how elements can be too larger to fit?

> The assert should possibly be made conditional on such too large
> blocks occuring when stride is too small

I'd be happy to add a condition to the assert, so that it becomes
useful, I just don't know what condition that could be.
But in its current form the assert is wrong, as it can be triggered
even though decoding works just fine.

Best regards,

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