[Ffmpeg-devel-irc] ffmpeg.log.20130304

burek burek021 at gmail.com
Tue Mar 5 02:05:01 CET 2013


[03:57] <defaultro> hopefully, I'll finish the timelapse howto video tonight :)
[04:18] <defaultro> hey folks, I seeing visual image quality loss using this command ->       ffmpeg -f image2 -r 24000/1001 -i timelapse_%04d.JPG -vcodec huffyyuv timelapse.mkv
[04:20] <defaultro> any tips so that whatever I see in my png is the same as what it will be in video? source png is already at 1920x1080
[04:20] <defaultro> or what's better than huffyuv
[04:31] <defaultro> i tried different encoding but all the words that are color red gets a little washed out compared to my sharp png file
[04:31] <defaultro> tried this, it didn't help - ffmpeg -y -loop 1 -i reencode.png -r 24000/1001 -vcodec libx264 -crf 0 -t 5 -preset veryslow -pix_fmt yuv420p reencode.png.mp4
[04:54] <defaultro> I tried these params too but red letters are still bleeding :( ffmpeg -f image2 -r 24000/1001 -i reencode%4d.png -vcodec huffyuv reencode.mkv
[05:00] <klaxa> blame color-space conversion
[05:01] <defaultro> not familiar with that
[05:01] <klaxa> using yuv444 instead of yuv420 should help
[05:01] <klaxa> or try using libx264rgb
[05:01] <defaultro> for vcodec?
[05:01] <klaxa> yeah
[05:01] <defaultro> ok
[05:03] <defaultro> I think I know the culprit
[05:03] <defaultro> it's not ffmpeg. It's my monitor :(
[05:04] <defaultro> it's not 1920 wide
[05:04] <defaultro> when I use ffplay, it displayed the original size which was way beyond my monitors width. The letters are not bleeding anymore. It was sharp
[05:05] <defaultro> so if my monitor was native 1920, it would have been fine
[05:05] <defaultro> but it's weird that when i display the png image whole screen, fonts are sharp
[05:05] <klaxa> ah heh
[05:05] <defaultro> that's when I got so confused
[05:07] <defaultro> i'll resize my image to 1600 and i'll check
[05:09] <defaultro> Bam! Monitor is the culprit. I resized my png image to 1600x900 and made a video using huffyuv. The fonts are sharp now at fullscreen
[05:10] <defaultro> that means, mplayer when it displays at fullscreen is not good in resizing
[05:19] <relaxed_> defaultro: I doubt it's mplayer's fault
[05:19] <defaultro> k
[05:20] <relaxed_> which -vo are you using?
[05:20] <defaultro> none, i just use mplayer -fs filename.mp4
[05:21] <relaxed_> use -vo gl or -vo xv
[05:28] <defaultro> ok
[05:28] <defaultro> relaxed_, it didn't help
[05:28] <defaultro> looks like the encoding is what's causing the the issue
[05:32] <defaultro> something I discovered very interesting. When color of font  is yellow, it is sharp. When color is red, it's washed out
[05:43] <defaultro> where can I upload my png image guys so you can try?
[06:00] <retro|cz> hello
[06:00] <retro|cz> I have one mp4 video file and I need to convert another files into same format as that mp4 video file. Is there any easy way how to get encoding params from that first video and use it for another videos?
[06:01] <klaxa> see if ffprobe gives you enough information
[06:01] <defaultro> someone from #mplayer told me that it;s a subsampling issue
[06:01] <defaultro> what is that
[06:01] <retro|cz> klaxa, https://gist.github.com/simi/5080068
[06:01] <retro|cz> I'm getting this.
[06:02] <klaxa> try mpeg4 as video codec for encoding
[06:03] <klaxa> i.e. ffmpeg -i <infile> -c:v mpeg4 <outfile>
[06:05] <retro|cz> klaxa, that's the spirit!
[06:05] <retro|cz> klaxa, thank you
[06:05] <klaxa> you're welcome :)
[06:06] <klaxa> if you have trouble, just ask again, different input files might need some more specific encoding information
[06:21] <retro|cz> klaxa, ok, i have another
[06:21] <retro|cz> I need to encode another version for flash player (flv).
[06:22] <klaxa> use outfile.flv
[06:22] <klaxa> ffmpeg should select the correct container
[06:22] <klaxa> i.e. ffmpeg -i some_file.mp4 -c:v mpeg4 outfile.flv
[06:23] <klaxa> and hope that it works, i never did stuff with flashplayer
[06:23] <retro|cz> I'm not sure about suffix.
[06:23] <retro|cz> flv or swf
[06:26] <klaxa> swf would be a flash animation
[06:26] <klaxa> flv is the flashvideo container format
[06:26] <retro|cz> klaxa, i made this
[06:26] <klaxa> actually i'm not so sure myself
[06:26] <retro|cz> ffmpeg -i $file -an -c:v flv1 $FLV
[06:26] <retro|cz> and it works
[06:27] <retro|cz> $FLV = file.swf
[06:27] <retro|cz> i should rename it
[06:27] <klaxa> ah okay then
[06:27] <retro|cz> web flash player can play it now
[06:27] <retro|cz> klaxa, thanks a lot
[06:27] <klaxa> np
[06:28] <retro|cz> ffmpeg told me I can't use mpeg4 for swf, only vp6,  flv1 or mjpeg
[10:52] <Wihl-w> Hello, I'm putting together some images with audio and it's working quite well
[10:53] <Wihl-w> "ffmpeg.exe" -loop 1 -y -i spt1.png -i Bild1.wav -shortest -acodec copy -vcodec mjpeg result.avi
[10:54] <Wihl-w> But there's a ton of png and wav files that I'd like to put together. All of them are named spt1.png spt2.png / Bild1.wav Bild2.wav etc
[10:54] <Wihl-w> Could I make a batch file to do it automatically? I'm pretty new to this
[12:26] <Net147> is there a video filter I can use in ffmpeg to output an image where each pixel in the output image is the pixel with the max intensity across all input video frames?
[13:25] <Wihl-w> Question, how can I join (concat?) an entire directory of videos using ffmpeg on windows?
[13:30] <retro|cz> Wihl-w, try http://ffmpeg.org/trac/ffmpeg/wiki/How%20to%20concatenate%20(join,%20merge)%20media%20files
[13:47] <Wihl-w> retro|cz: hm, not sure if i'm doing it wrong
[13:47] <Wihl-w> "ffmpeg.exe" -i "concat:result1.avi|result6.avi" -c copy output.avi
[13:48] <Wihl-w> that just gives me an output.avi with the content of result1.avi, result6.avi is MIA
[14:24] <retro|cz> Wihl-w, you need to specify -f concat also
[14:24] <retro|cz> ohh, probably not
[14:24] <retro|cz> Are those files in same format?
[14:28] <Wihl-w> yes
[14:34] <Wihl-w> used mencoder to join them instead, worked nicely
[14:38] <retro|cz> Wihl-w, gj :)
[15:33] <Bor0> hi. I am using ffmpeg libs and working on a frame accurate player. so basically ffplay has the option to step 1 frame forward, but what about stepping 1 frame backwards?
[15:59] <Yulth> join #foobar2000
[15:59] <Yulth> sorry :)
[16:00] <spaam> fail
[16:06] <Kirito> Can I have ffmpeg generate screenshots with subtitles being displayed properly?
[16:07] <Kirito> Or possibly with mplayer?
[16:45] <bchapman> Hello, I'm having a problem with ffmpeg that I can't figure out, any help would be greatly appreciated! My issue is that the first frame of my encoded videos is doubled.  Here's my command: ffmpeg -y -loglevel debug -i "/Volumes/Files/tmp/ffmpegTests/test070.mp4" -c:v mjpeg "/Volumes/Files/tmp/ffmpegTests/test070_ffmpeg.mov"
[16:45] <bchapman> I can send whatever logs you need
[17:51] <smellynosery> Hi - how can I find out who wrote the majority of the mpegts encoder?
[17:53] <smellynosery> I want to hire them, not shout verbal abuse at them btw :)
[17:53] <Trashlord> probably with google
[17:54] <Trashlord> search for the project in google
[17:54] <Trashlord> see if there's an official website
[17:54] <Trashlord> if there is, try to contact them, there's usually an email or something left there
[17:57] <cbsrobot_> smellynosery: git blame ?
[17:58] <smellynosery> cbsrobot_: perfect, thanks
[17:59] <cbsrobot_> smellynosery: are you talking about the format or the mpeg codec ?
[17:59] <smellynosery> cbrrobot_: livavformat/mpegtsenc.c
[18:05] <cbsrobot_> smellynosery:
[18:05] <cbsrobot_> 427 author Fabrice Bellard
[18:05] <cbsrobot_>  156 author Jindrich Makovicka
[18:05] <cbsrobot_>  119 author Baptiste Coudurier
[18:05] <cbsrobot_>   83 author Mike Scheutzow
[18:05] <cbsrobot_>   58 author Michael Niedermayer
[18:06] <cbsrobot_> although I do not think Fabrice Bellard wants to work on it ...
[18:07] <retro|cz> cbsrobot_, better to find someone active recently - http://git.libav.org/?p=libav.git;a=shortlog;h=HEAD
[18:07] <retro|cz> sorry, here http://git.libav.org/?p=libav.git;a=history;f=libavformat/mpegtsenc.c;h=29d83c668ab1c665cd5370ffa6c6a163b1ef5641;hb=HEAD
[18:09] <cbsrobot_> retro|cz or even http://git.videolan.org/?p=ffmpeg.git;a=history;f=libavformat/mpegtsenc.c;h=56b9d8506ab82d708e22e08c1a6452d1ebf0d674;hb=HEAD
[18:09] <smellynosery> Brilliant - thankyou
[18:09] <retro|cz> libav is some kind of fork I think
[20:31] <msmithng> I asked a couple days ago but here's the question again...
[20:31] <msmithng> is there anyway for me to tell ffprobe to skip stream 0, in the event of input that has no audio?
[20:32] <msmithng> getting:
[20:32] <msmithng> [mpegts @ 0x10200e800] max_analyze_duration 5000000 reached at 5003333
[20:32] <msmithng> [mpegts @ 0x10200e800] Could not find codec parameters for stream 0 (Unknown: none ([21][0][0][0] / 0x0015)): unknown codec
[20:32] <msmithng> Consider increasing the value for the 'analyzeduration' and 'probesize' options
[20:32] <msmithng> I'll keep an eye out for a reply, otherwise I'll just shoot it to the list.
[22:50] <bchapman> I'm having some trouble decoding h264 files. I've tested with multiple files. I end up having to use -ss to seek 1 frame forward, or the first frame is duplicated. For audio I have to seek 2ms forward, or it doesn't line up. Ideas?
[00:00] --- Tue Mar  5 2013


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