Hi,

On Mon, Jun 13, 2011 at 9:49 PM, Eric Glaser <[email protected]> wrote:
> On Sun, Jun 12, 2011 at 7:13 PM, Tristan Matthews
> <[email protected]> wrote:
>> 2011/6/12 Ronald S. Bultje <[email protected]>
>>>
>>> Hi,
>>>
>>> On Sun, Jun 12, 2011 at 1:56 PM, Eric Glaser <[email protected]> wrote:
>>> > Hi, I am having some trouble converting from YUYV to RGB format - it
>>> > crashes in sws_scale.
>>>
>>> Can you provide a backtrace?
>>>
>>> >            int numRGBBytes = ww * hh * 4;   //src width * src height * 4
>>> >            buffer = malloc (sizeof(uint8_t)*numRGBBytes);
>>>
>>> Use av_malloc(), malloc() return values are not aligned and crash
>>> randomly when using SIMD functions.
>>
>> libavcodec/api-example.c uses malloc in a similar context, instead of
>> av_malloc. Should this be updated?
>>
>> -T
>>
>>>
>>> >        int ret = sws_scale(pOGLContext->img_convert_ctx,
>>> > (uint8_t**)pFrame->data, pFrame->linesize, 0, hh, pFrameRGB->data,
>>> > pFrameRGB->linesize);
>>>
>>> So here it crashes? That's likely in the runtime-generated MMX code
>>> then. Again, can you provide a backtrace, and then the output (in gdb)
>>> "disass $pc-32,$pc+32" and "info all-registers".
>>>
>>> Ronald
>>> _______________________________________________
>>> libav-api mailing list
>>> [email protected]
>>> https://lists.libav.org/mailman/listinfo/libav-api
>>
>>
>>
>> --
>> Tristan Matthews
>> web: http://tristanswork.blogspot.com
>>
>
> Hi Thanks for replying.
>
> It crashes inside libswscale function - but I noticed sometimes it
> goes thru however nothing but some garbled pixels show up on the
> screen. It might be my v4l reader not providing valid data. Resolution
> is 720 x 576, format YUYV.
>
> (gdb) bt
> #0  0x00007ffff005d4f0 in ?? () from /usr/local/lib/libswscale.so.0
> #1  0x00007ffff0060f5a in ?? () from /usr/local/lib/libswscale.so.0
> #2  0x00007ffff0063987 in sws_scale () from /usr/local/lib/libswscale.so.0

Can you try to compile ffmpeg with debug symbols, and possibly with
CFLAGS="-fno-omit-frame-pointer -O0"? That makes debugging easier.

Thanks,
Ronald
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