[Ffmpeg-devel-irc] ffmpeg.log.20130413

[burek]

[10:27] <dv--> what I'm recording:
[10:28] <dv--> oops. what I'm recording: http://i.imgur.com/2w3C7RX.png, ffmpeg -q 0: http://i.imgur.com/5WJXXoQ.png
[10:28] <dv--> is there any way to improve that?
[10:32] <relaxed> dv--: ? png is lossless
[10:34] <dv--> http://pastebin.com/q8N8Qpt0
[10:35] <relaxed> you want lossless?
[10:36] <dv--> i'd like something closer to lossless than what i'm getting
[10:36] <relaxed> try -crf 20
[10:37] <dv--> the orange text in particular looks really bad
[10:37] <relaxed> lower the value for higher quality
[10:37] <dv--> isn't -q 0 already -crf 0?
[10:38] <relaxed> -qp 0
[10:40] <dv--> i tried it but with -q 0 -qp 0 it looks identical to just -q 0
[10:44] <relaxed> did you try -crf 0?
[10:45] <dv--> yeah, it's the same
[10:47] <relaxed> show me the pastebin
[10:49] <dv--> http://pastebin.com/bWbWgurP
[10:51] <dv--> if I use yuv420p it looks even worse
[10:52] <LithosLaptop> and if you use libx264rgb?
[10:54] <dv--> hm
[10:54] <dv--> i can't play it with vlc, looks terrible in mplayer (very desaturated), also when recording i'm getting alsa buffer xruns
[10:55] <LithosLaptop> hmm ok
[10:57] <dv--> maybe i'll just live with slightly suboptimal font rendering
[11:01] <LithosLaptop> tried huffyuv or ffv1?
[11:02] <dv--> huffyuv works but the files are huge
[11:02] <dv--> i'll try ffv1
[11:02] <relaxed> it's strange you getting bad quality with libx264 lossless
[11:02] <relaxed> it should look exactly the same
[11:03] <LithosLaptop> yeah
[11:08] <LithosLaptop> dirac has a lossless mode, but I am not sure how one specifies it in ffmpeg
[11:31] <cryptopsy> after i used ffmpeg to make an avi from an mp3, sound doesn't work, and /etc/init.d/alsa restart, doesn't fix it
[11:33] <cryptopsy> what for?
[11:34] <burek> for the balance among the stars..
[11:34] <cryptopsy> $FFMPEG -loop 1 -i $1 -i $2 -vcodec mpeg4 -threads 4 -acodec copy -y -t $TIME $3
[11:34] <burek> forget it
[11:34] <cryptopsy> that's it
[11:37] <cryptopsy> burek: alsa can i eat a dick, i can reboot after saving my instance instead of wasting hours debugging for the alsa team
[11:37] <cryptopsy> can eat*
[11:37] <burek> dv--, relaxed, does bgr0 -> yuv444p has got anything to do with that
[11:37] <cryptopsy> have no idea who you're talking to
[11:37] <burek> it's ok, i know who am i talking to and that's all that matters
[11:38] <cryptopsy> k then i'll disregard
[12:14] <dv--> burek: how would I check that...
[12:15] <burek> dv--, try something like: ffmpeg ... -vcodec libx264 -pixel_format yuv420p ...
[12:16] <dv--> yeah i've tried yuv420p. it looks worse
[12:20] <LithosLaptop> and libx264rgb doesn't work in vlc?
[12:23] <dv--> it looks solid green
[12:28] <LithosLaptop> ah ok
[12:28] <LithosLaptop> and yuvj444p?
[12:29] <LithosLaptop> the j was intentional
[12:54] <burek> if you used -crf 0 then only thing that could change the visual perception of colors is the colorspace conversion due to changing pixel formats, i guess..
[12:57] <LithosLaptop> yuvj444p is 0-255 and yuv444p is 16 to 235 I think
[16:50] <dregan> hi guys, who has a link to latest ffmpeg compiled or rpm for centos 6?
[18:23] <burek> dregan
[18:30] <JodaZ> 2.4 ?
[21:48] <elkng> http://sprunge.us/VceO those are 4 commands I use to convert same "mkv" video into "avi" but using different bitrate, and http://sprunge.us/LTDL are "avi" files, but they have bitrate not that I expected, those are "800.avi - 939 kb/s" "1000.avi 1139 kb/s" "1200.avi 1142 kb/s" "1500.avi 1143 kb/s", file that should be about 800 kb/s bitrate is quite close to that bitrate but others that should be close to 1000,1200,1500 arn't they are all about same bitrat
[21:48] <elkng>  codec decides to make it that way ?
[21:52] <elkng> any ideas of that behaviour ? I'm using ffmpeg version 1.2
[22:24] <relaxed> The encoder probably can't use that many bits for the given source.
[22:24] <relaxed> Just because you use -b:v 1000000000M doesn't mean the encoder can comply :)
[22:37] <elkng> now that I think about it initial mkv video has 1333 kb/s bitrate
[22:38] <elkng> so it can't be converted to 1500 kb/s ?
[23:07] <cbreak> sure it can
[23:07] <cbreak> just add noise
[23:07] <cbreak> or something else that's hard to compress
[23:07] <cbreak> then reencode
[23:07] <cbreak> of course the quality will suffer, but you will get a bigger file
[23:24] <elkng> you eat clowns on breakfast ?
[00:00] --- Sun Apr 14 2013