[FFmpeg-user] Video quality

Reindl Harald h.reindl at thelounge.net
Mon Dec 12 18:56:03 CET 2011



Am 12.12.2011 18:51, schrieb Hans Guth:
> I have an flv video that is about 38M and the quality is excellent.  When I try and convert it to SWF which is
> format I need I can't seem to get a quality output file.  The original file is 1920x1088.  I want the output to be
> 640x480 but whatever I am doing it's creating a very choppy output file.
> 
> I have tried all sorts of different settings but if size is set to 640x480 then I seem to get same/similar
> results.  Note: If I set -sameq then the swf output seems to get screwed up - i.e. it won't start playing but gets
> hung on frame 1?
> 
> /usr/local/bin/ffmpeg -i MOV072.flv -y -s 640x480 -r 30000/1001 -b 200k -bt 240k MOV072.swf
> 
> Seems stream 0 codec frame rate differs from container frame rate: 59.94 (2997/50) -> 29.92 (359/12)
> Input #0, flv, from 'MOV072.flv':
>   Duration: 00:00:42.71, start: 0.000000, bitrate: 264 kb/s
>     Stream #0.0: Video: h264, yuv420p, 1920x1088, 200 kb/s, 29.92 tbr, 1k tbn, 59.94 tbc
>     Stream #0.1: Audio: mp3, 22050 Hz, stereo, s16, 64 kb/s
> Output #0, swf, to 'MOV072.swf':
>     Stream #0.0: Video: flv, yuv420p, 640x480, q=2-31, 200 kb/s, 90k tbn, 29.97 tbc
>     Stream #0.1: Audio: libmp3lame, 22050 Hz, stereo, s16, 64 kb/s

having a high compressed input with 200 kbit and convert it
again with a non-losless format with such a low bitrate
leaves no option as a degraded quality

200kbit may be ok if you have really HQ input

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 262 bytes
Desc: OpenPGP digital signature
URL: <http://ffmpeg.org/pipermail/ffmpeg-user/attachments/20111212/6ca78b5d/attachment.asc>


More information about the ffmpeg-user mailing list