René J.V. Bertin <rjvbertin@...> writes: > On Dec 08, 2012, at 00:06, Carl Eugen Hoyos wrote: > > My guess now is that you argue that for two given codecs (no > > matter if mjpeg, mpeg-4 asp, mpeg2video, flv1 or snow), the > > following command line always produces files of nearly identical > > size: > > $ ffmpeg -i input -vcodec xxx out.avi > > No, not always, but for the files I'm working with. When I compare > > > ffmpeg -i 4000kbaud.m4v -vcodec copy out1.mov > > ffmpeg -i 4000kbaud.m4v -vcodec mpeg4 -b:v 4000k out2.mov > > ffmpeg -i 4000kbaud.m4v -vcodec mjpeg -b:v 1150k out3.mov
(I don't think -vcodec mjpeg supports setting a bitrate, sorry I did not really consider this.) > I get 3 output movies that are all at (approximately) > 4000kbits/s, and all approximately the same size as > the input. > You may not agree, but it my experience that material > that has already been compressed with a lossy codec is > often hard to compress further This is true for material that has been compressed with maximum quantiser but this does not seem like a typical use-case to me. Carl Eugen _______________________________________________ Libav-user mailing list [email protected] http://ffmpeg.org/mailman/listinfo/libav-user
