[FFmpeg-devel] [PATCH] flag CODEC_FLAG2_RETURN_INCOMPLETE_FRAMES

[Reimar Döffinger]

On Sat, Dec 11, 2010 at 03:05:09PM -0800, Jason Garrett-Glaser wrote:
> > does your solution have an advantage over what i suggested? ?That is
> > implementing what is written in
> > "7.4.1.2.4 Detection of the first VCL NAL unit of a primary coded picture"
> > that way a picture would be returned once the first slice of the next is
> > feeded in or something like a access unit delimiter is inserted
> > ?
> 
> I don't know, but take the following example.
> 
> Suppose frame 10 has 5 slices.  The last goes missing.  Frame 11 has 1 slice.
> 
> We tell libavcodec to decode frame 10, slice by slice.  The last is
> missing, so it doesn't give us a frame back.
> 
> Then we tell libavcodec to decode frame 11, slice by slice.  It now
> has to give us both frame 10 and 11 -- at the same time.  I don't
> think the libavcodec API supports that.

Well, I am a bit confused about the API, but there would be two
possibilities
1) returning AVERROR(EAGAIN). Problem: I think this is already misused
   in AAC decoder to mean "please provide next data chunk".
2) returning 0 to indicate none of the data was processed. The
   problem is that the documentation specifies this to mean
   "zero if no frame could be decompressed" which is rather
   silly since the got_picture_ptr parameter already indicates that...