On Thu, 2010-07-01 at 02:28 -0700, Mike Gratsas wrote:
> I have several questions regarding your FFmpeg library:

I'll answer the ones I have answers to :)

> 
> 2. If I undersand properly that swscale currently can't accept pal8 as 
> destination pixel format? I created destination picture using 
> avcodec_alloc_frame and avpicture_alloc functions, but got an exception 
> trying to convert using sws_scale function.

Correct

> 
> 3. Could you clear how to extract a frame at the specified timestamp 
> position? I'm seeking to the key frame using function av_seek_frame with 
> AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD flags, then avcodec_flush_buffers 
> function is called to flush buffers. However, after reading packet using 
> av_read_frame function I found avcodec_decode_video returns argument 
> got_picture = 0 and I need to read several following packets to obtain video 
> frame finally.

Take a look at how ffplay.c handles this. Specifically around line 1521
(reordered_opaque).

> 
> 4. Could you add some exportable function to detect bits per sample for a 
> given pixel format? As I understand it is impossible currently since field 
> bits_per_coded_sample in AVCodecContext structure is not filled by some 
> decoders.

av_get_bits_per_pixel()

/Tomas

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