[FFmpeg-devel] [PATCH] lavfi: Port fspp to FFmpeg

[Stefano Sabatini]

On date Monday 2014-12-22 17:57:34 +0100, Reimar Döffinger encoded:
> On 22.12.2014, at 17:23, Stefano Sabatini <stefasab at gmail.com> wrote:
[...]
> > I'm testing with:
> > ffmpeg -i matrixbench_mpeg2.mpg -b:v 200k matrixbench_mpeg2-lq.mpg
> > 
> > ffplay -f lavfi -i "nullsrc=s=720x576 [bg]; movie=matrixbench_mpeg2-lq.mpg:s=dv+da [v][out1]; [v]split[v1][v2]; [v1]crop=in_w/2:in_h:0:0 [v1pp]; [v2]crop=in_w/2:in_h:in_w/2:0,fspp [v2pp]; [bg][v1pp] overlay[bg+v1pp]; [bg+v1pp][v2pp] overlay=W/2 [out0]"
> > 
> > I'm unable to see significant differences in terms of quality between
> > left and right part of the output (same with mp=fspp, so it doesn't
> > depend on the port).
> > 
> > Is this expected?
> > 
> > What's the use case of fspp?
> 
> What codec did your lq version end up using? I suspect fspp is most
> tested and works best with MPEG-4 ASP.  It should significantly
> reduce blocking - obviously only if your video has significant
> blocking.  It used to work fairly well on early flv streaming
> videos.

Output #0, mpeg, to 'matrixbench_mpeg2-lq.mpg':
  Metadata:
    encoder         : Lavf56.16.101
    Stream #0:0: Video: mpeg1video, yuv420p, 720x576 [SAR 16:15 DAR 4:3], q=2-31, 200 kb/s, 25 fps, 90k tbn, 25 tbc
    Metadata:
      encoder         : Lavc56.16.100 mpeg1video
    Stream #0:1: Audio: mp2, 48000 Hz, stereo, s16, 384 kb/s
    Metadata:
      encoder         : Lavc56.16.100 mp2
Stream mapping:
  Stream #0:1 -> #0:0 (mpeg2video (native) -> mpeg1video (native))
  Stream #0:2 -> #0:1 (mp2 (native) -> mp2 (native))
-- 
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