[Ffmpeg-devel-irc] ffmpeg.log.20111224

burek burek021 at gmail.com
Sun Dec 25 02:05:01 CET 2011


[00:03] <u0m3> caytchen: the lib... I mentioned the ffmpeg command line tool because I tryed to check out how it handles resampling when passed the argument -ar <val> within it's code. But as I said, the argument handling is well hidden
[00:07] <caytchen> okay, then my hints still apply. the process of resampling (with ReSampleContext or swresample) is pretty straightforward and simple though. swresample is a bit more convoluted since its designed for multiple audio channels in multiple buffers, not the packed audio that I think every ffmpeg audio codec outputs.
[00:09] <caytchen> theres one function that allocates the context and initializes it with your specifications and then one convert function that you use to move data in and get freshly resampled out.
[00:10] <u0m3> caytchen: actually I need to check for multiple audio channels... I need to get sound data into a buffer at 48kHz / stereo / signed 16bit / pcm or wave ... so I guess I'll have to use swresample...
[00:16] <caytchen> well yes, you have multiple channels, but if you're using ffmpeg to get the raw audio data, chances are it will be in one big buffer despite having multiple channels
[00:16] <u0m3> caytchen: by big buffer you mean the whole file in a buffer at once?
[00:21] <caytchen> say I have a stereo MP3 file. I have ffmpeg decode a frame into an AVFrame. AVFrame actually has seperate data buffers for seperate channels, so you would expect the two stereo channels to be decoded into their own buffers.
[00:21] <caytchen> but what actually happens is that all the data ends up in the first buffer, samples for left and right are packed together.
[00:23] <u0m3> caytchen: better that way... I need to send the buffer to another lib and it expects all the channels in a single buffer.
[00:24] <caytchen> its kind of a moot point anyway, all I wanted to say is that swresample has facilities for audio data being split by channels, but you can still just give it the packed data, too.
[00:25] <u0m3> ah, got it.
[03:02] <shevy> [aac @ 0x893b7e0]Reserved SBR extensions are not implemented. Update your FFmpeg version to the newest one from Git. If the problem still occurs, it means that your file has a feature which has not been implemented.
[03:02] <shevy> [aac @ 0x893b7e0]If you want to help, upload a sample of this file to ftp://upload.ffmpeg.org/MPlayer/incoming/ and contact the ffmpeg-devel mailing list.
[03:02] <shevy> hmm
[03:03] <shevy> is this bad? the file in question seems to play just fine, audio is also fine ... other than those warning messages I'd say everything is perfect
[04:11] <aixenv> hey i just noticed that my faac doesn't work anymore, what is the new audio standard to use?
[04:11] <aixenv> my encoding log shows 'usr/share/ffmpeg/libx264-slow.ffpreset: Invalid option or argument: 'rc_lookahead=50', parsed as 'rc_lookahead' = '50'
[04:12] <aixenv> the params i was using were: ffmpeg -y -i "$file" -vcodec libx264 -r 30000/1001 -deinterlace -s 1024x576 -crf 21 -maxrate 2M -bufsize 6M -vpre slow -threads 0 -acodec libfaac -ar 48000 -ab 128k ${file%.*}-1.mp4 >> "${file%}"-encoding.out 2>&1
[04:15] <treund> aixenv: what does ffmpeg -codecs | grep faac   show
[04:17] <aixenv> that option doesnt work
[04:17] <aixenv> the "-codecs"
[04:17] <treund> ? i get as a last line after the configure info   128:  EA    libfaac         libfaac AAC (Advanced Audio Codec)
[04:18] <aixenv> ffmpeg: missing argument for option '-codec'
[04:18] <caytchen> -codec_s_
[04:20] <aixenv> well -formats works
[04:20] <aixenv>  D  aac             raw ADTS AAC
[04:20] <aixenv>  D A    aac             Advanced Audio Coding
[05:29] <aixenv> any ideas?
[05:39] <relaxed> aixenv: about what?
[05:43] <aixenv> my encoding log shows 'usr/share/ffmpeg/libx264-slow.ffpreset: Invalid option or argument: 'rc_lookahead=50', parsed as 'rc_lookahead' = '50'
[05:43] <aixenv> the params i was using were: ffmpeg -y -i "$file" -vcodec libx264 -r 30000/1001 -deinterlace -s 1024x576 -crf 21 -maxrate 2M -bufsize 6M -vpre slow -threads 0 -acodec libfaac -ar 48000 -ab 128k ${file%.*}-1.mp4 >> "${file%}"-encoding.out 2>&1
[05:54] <relaxed> aixenv: replace '-vpre slow' with '-preset slow'
[05:54] <aixenv> testing
[05:57] <relaxed> and if possible, replace '-deinterlace -s 1024x576' with '-vf "yadif,scale=1024:576"'
[05:57] <aixenv> ok i can do whatever you recommend, whats the reason on that one?
[05:58] <relaxed> yadif is better at deinterlacing
[05:59] <aixenv> ty - testing
[06:01] <aixenv> i get unrecognized -vf
[06:02] <aixenv> is my ffmpeg too old? i have an svn -r0.5.5-1 version
[06:02] <relaxed> yes
[06:02] <aixenv> ok let me update my svn
[06:02] <relaxed> uh, no
[06:02] <aixenv> is it ok to still use libfaac or should i be using something else now?
[06:02] <relaxed> ffmpeg now uses git
[06:02] <aixenv> ok
[06:03] <aixenv> git://source.ffmpeg.org/ffmpeg.git <== right?
[06:03] <relaxed> correct
[06:03] <aixenv> ok hang tight let me grab the source
[06:03] <aixenv> my config options are
[06:03] <relaxed> libfaac is fine but you'll need to pass --enable-nonfree to configure
[06:04] <aixenv> --prefix=/usr --enable-avfilter --enable-avfilter-lavf --enable-vdpau --enable-bzlib --enable-libdirac --enable-libgsm --enable-libopenjpeg --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-pthreads --enable-zlib --disable-stripping --disable-vhook --enable-runtime-cpudetect --enable-gpl --enable-postproc --enable-swscale --enable-x11grab --enable-libfaad --enable-libdc1394 --enable-shared --disa
[06:04] <aixenv> ble-static
[06:04] <aixenv> any issues with that nowadays?
[06:05] <relaxed> yes, one second
[06:05] <aixenv> ok thank you for the help, much appreciated
[06:08] <relaxed> --prefix=/usr --enable-vdpau --enable-libdirac --enable-libgsm --enable-libx264 --enable-libopenjpeg --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --disable-stripping --enable-x11grab --enable-libfaac --enable-nonfree --enable-libdc1394 --enable-shared --disable-static
[06:08] <relaxed> Do you need all of that?
[06:10] <aixenv> yes i believe so
[06:10] <aixenv> possibly now libspeez
[06:10] <aixenv> *speex
[06:10] <aixenv> sorry *not
[06:11] <relaxed> you may need it for decoding
[06:12] <aixenv> ok, so that line you gave me should suit my initial command right?
[06:12] <relaxed> yes, if you're buuilding a package for use on other machines add --enable-runtime-cpudetect
[06:12] <aixenv> ok
[06:13] <aixenv> needed -enable-gp too
[06:13] <aixenv> --enable-gpl
[06:15] <aixenv> ERROR: libdc1394-2 not found ; finding and making
[06:16] <relaxed> I doubt you need it.
[06:16] <relaxed> Do you use ffmpeg to read DV over firewire?
[06:17] <aixenv> no -ill omit
[06:19] <aixenv> probably dont need libdirac either, never use that
[06:26] <aixenv> what about openjpeg that needed for basic use?
[06:37] <relaxed> no
[06:55] <aixenv> i ended up using "--prefix=/usr --enable-vdpau --enable-libx264 --enable-libtheora --enable-libvorbis --disable-stripping --enable-x11grab --enable-libfaac --enable-nonfree --enable-shared --disable-static --enable-runtime-cpudetect --enable-gpl --enable-libmp3lame --enable-libspeex --enable-xvid --enable-pthreads --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-postproc --enable-libvpx --enable-version3"
[07:12] <aixenv> there we go - ffmpeg version N-36147-g64cafe3, Copyright (c) 2000-2011 the FFmpeg developers
[07:12] <aixenv> now to test
[07:35] <aixenv> WOOT fixed
[08:24] <ablegreen> hi
[08:24] <ablegreen> i have a question about live webcam streaming
[08:26] <ablegreen> i guess no one is here
[08:30] <ablegreen> styles, you there?
[08:30] <ablegreen> anyoneeeee here?
[17:45] <h_senior_paris> good evening , does anybody already succeeded on encoding a webcam to H264 format and flv container ?
[19:31] <praedo> hello
[19:31] <praedo> merry xmas first of all
[19:31] <praedo> i have a problem deinterlacing a video
[19:31] <praedo> the DV tape was corrupt at some point and the capture must be missing some bit
[19:32] <praedo> the image is good but deinterlacing presents a weird blinking when the camera is moved
[19:32] <praedo> still images are viewed fine
[19:32] <praedo> i always did it the same way and deinterlacing worked
[19:32] <praedo> now the difference is the corrupt tape
[19:33] <praedo> i export with adobe premiere as i always do, using PAL DV
[19:33] <praedo> the original DV file before being edited doens't present this blinking problem
[19:33] <praedo> only after edited and exported
[19:34] <praedo> i tried to encode into mp4 without using deinterlace and the image is interlaced but without the blinking problem
[19:34] <praedo> so the problem is at the deinterlace point
[19:34] <praedo> with this description of the problem, what kind of deinterlace technique do you suggest to fix it?
[19:35] <praedo> thanks in advance for any advice
[19:47] <praedo> maybe using yadif?
[19:56] <iive> praedo: afaik dv is key-frame only, so there shouldn't be long lasting effects. my guess is that field dominance is guessed wrong.
[19:56] <iive> aka whatever the upper or bottom field is displayed first. so in effect, it should appear like every 2 frames are swapped. 
[19:57] <iive> or in other words, the motion would be doing 2 steps forward and one backward.
[21:57] <praedo> iive, yes, that seems to be the problem
[21:57] <praedo> any solution for it?
[22:00] <iive> praedo: not sure. I see there is -top option, but not sure how it works. I think yadif should have field dominance parameter too.
[22:00] <praedo> what field dominance it should be?
[22:01] <iive> donno... depends on the source
[22:38] <praedo> i tried many deinterlacing options and none of them succees
[22:39] <praedo> succeeds
[22:39] <praedo> could you have a look with a 30sec. sample?
[22:42] <praedo> iive, can you try to encode it for me?
[22:42] <praedo> just the sample to check
[22:48] <iive> ok
[22:55] <praedo> thanks iive, where can i send it to you?
[22:55] <iive> praedo: donno, try dcc
[22:55] <praedo> i have just tried mpeg streamclip setting both upper field and then lower field for dominance and result is worse than seeing it interlaced
[22:56] <praedo> it must be something else
[22:56] <praedo> please have a look to it
[22:56] <praedo> i upload to megaupload, okay?
[22:57] <iive> ok.
[22:57] <praedo> thanks
[22:57] <iive> it does (still) allow download without buying premiums
[23:02] <praedo> uploading... 39mb for 10 seconds
[23:02] <praedo> recently exported into PAL DV from the edited piece
[23:03] <praedo> as i always do it
[23:12] <praedo> finished!
[23:12] <praedo> http://www.megaupload.com/?d=F7NPMCII
[23:12] <praedo> you can download it without need to have premium
[23:15] <praedo> iive, let me know if it downloads fine
[23:35] <praedo> any luck encoding, iive?
[23:45] <iive> oops, got carried away.
[23:46] <iive> downloaded. 
[23:48] <cbsrobot> praedo: my guess: broken ccd
[23:49] <cbsrobot> every 8 to 9th frame the interlacing is broken
[23:49] <iive> praedo: is that the original footage?
[23:49] <iive> it looks like it have been scaled like it is progressive, thus bleeding interlace into the opposite fields
[23:53] <praedo> as i explained before, the tape is corrupt at the beginning
[23:53] <iive> no
[23:54] <iive> this have nothing to do with corruption
[23:54] <praedo> when i play the tape on the camera itself, it shows scrambled frames for some seconds, then the recording starts playing fine
[23:54] <iive> as dv is keyframe only format, it should not be affected if portion of it is missing.
[23:54] <praedo> the captured file also plays fine without this problem (being interlaced)
[23:55] <praedo> the problem occurs after exporting to PAL DV as usual
[23:55] <praedo> i always deinterlace that PAL DV material and plays fine
[23:55] <praedo> but in this case it refused to be deinterlaced by all methods i tried
[23:55] <praedo> maybe i'm just missing some option that i don't know
[23:56] <iive> no
[23:57] <praedo> then maybe i should try to swap opposite fields?
[23:57] <iive> the sample you gave me is permanently damaged.
[23:57] <praedo> all the 1-hour conference looks like this
[23:57] <praedo> and i need to deliver it to the customer...
[23:58] <iive> repairing it is enormous  mathematical challenge
[23:58] <praedo> still images aren't affected
[23:58] <praedo> how come?
[23:58] <mystica555_> praedo: is that sample you posted to megaupload, the raw footage?
[23:58] <iive> i tried to play it with mplayer using -vf il=d:d , this separates both fields and makes them as 2 whole picture one above the other.
[23:59] <praedo> no, that sample is the exported PAL DV after being edited with premiere
[23:59] <mystica555_> whats the input source?
[23:59] <praedo> the raw is 10gb
[23:59] <iive> some of the fields are looking like sine waves.
[23:59] <mystica555_> is it also pal-dv?
[23:59] <mystica555_> premiere deals with interlacing......badly
[23:59] <praedo> the input source is dv tape from dvx100 camera
[00:00] --- Sun Dec 25 2011


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