[FFmpeg-devel] lavfi state of affairs

[Vitor Sessak]

Michael Niedermayer wrote:
> On Sun, Feb 08, 2009 at 07:10:22PM +0100, Vitor Sessak wrote:
>> Michael Niedermayer wrote:
>>> On Sun, Feb 08, 2009 at 01:39:02PM +0100, Vitor Sessak wrote:
> [...]
> 
>>> could you please use unambigous command lines that do not depend on
>>> automatcally inserted scale filters!
>> ffmpeg -i in.avi -vfilters "format=rgb32, scale=256:256,format=rgb32, 
>> fifo,slicify=32, format=yuv410p, fifo" out.avi
> [...]
>> [format @ 0x88b9170]auto-inserting filter 'scale'
>> [format @ 0x88be990]auto-inserting filter 'scale'
>> [fifo @ 0x88ef990]auto-inserting filter 'scale'

It do not _depends_ on auto-inserted filters, but I understand what you 
mean:

http://samples.mplayerhq.hu/V-codecs/IV32/levis.avi

(any other YUV410P sample should do it)

vitor at vitor-laptop:~/ffmpeg/ffmpeg.lavfi$ ./ffmpeg_g -an -i 
/tmp/levis.avi -vfilters slicify=32,scale -pix_fmt yuv420p -vcodec 
rawvideo -y /tmp/out.avi
FFmpeg version SVN-r18763, Copyright (c) 2000-2009 Fabrice Bellard, et al.
   configuration: --cc='ccache gcc' --enable-avfilter
   libavutil     50. 3. 0 / 50. 3. 0
   libavcodec    52.28. 0 / 52.28. 0
   libavformat   52.32. 0 / 52.32. 0
   libavdevice   52. 2. 0 / 52. 2. 0
   libavfilter    0. 5. 0 /  0. 5. 0
   libswscale     0. 7. 1 /  0. 7. 1
   built on May  6 2009 20:31:12, gcc: 4.2.4 (Ubuntu 4.2.4-1ubuntu3)
Input #0, avi, from '/tmp/levis.avi':
   Duration: 00:00:44.83, start: 0.000000, bitrate: 352 kb/s
     Stream #0.0: Video: indeo3, yuv410p, 152x116, 6 tbr, 6 tbn, 6 tbc
     Stream #0.1: Audio: 0x0031, 44100 Hz, mono, s16, 71 kb/s
Output #0, avi, to '/tmp/out.avi':
     Stream #0.0: Video: rawvideo, yuv420p, 152x116, q=2-31, 200 kb/s, 6 
tbn, 6 tbc
Stream mapping:
   Stream #0.0 -> #0.0
Press [q] to stop encoding
frame=  269 fps=  0 q=0.0 Lsize=    6960kB time=44.83 
bitrate=1271.7kbits/s
video:6948kB audio:0kB global headers:0kB muxing overhead 0.170581%

The video is obviously distorted. Note that if you remove "slicify=32" 
from the command line, there is no distortion.

-Vitor