[LAD] Screencasting with JACK [SOLVED!]

F. Medeiros excalibas at gmail.com
Fri Sep 27 08:36:11 UTC 2013


On 09/26/2013 05:44 PM, J. Liles wrote:
>
> On Thu, Sep 26, 2013 at 8:16 AM, F. Medeiros <excalibas at gmail.com 
> <mailto:excalibas at gmail.com>> wrote:
>
>     Hello,
>
>     I have the same problem, audio and video are not in sync and  the
>     data is not aligned Warning.
>     This also happens when using Xephyr.
>
>
>     This is what I get from ffmpeg:
>
>     x at space:~/Documents/ffmpeg$ ./ffmpeg -fflags +genpts+igndts -f
>     x11grab -vsync 0 -r 30 -s 1920x1080 -i :1.0+0,0 -vcodec h264 -f
>     jack -ac 2 -r:a 48000  -i screencast -acodec pcm_s16le -r:v 30
>     -vsync 2 -async 1 -map 0:0,1,0 -map 1:0 -preset ultrafast -qp 0
>     test.mkv
>     ffmpeg version N-56669-g1906e00 Copyright (c) 2000-2013 the FFmpeg
>     developers
>       built on Sep 26 2013 11:48:30 with gcc 4.6 (Ubuntu/Linaro
>     4.6.3-1ubuntu5)
>       configuration: --enable-libvorbis --enable-gpl --enable-libx264
>     --enable-x11grab
>       libavutil      52. 46.100 / 52. 46.100
>       libavcodec     55. 33.100 / 55. 33.100
>       libavformat    55. 18.102 / 55. 18.102
>
>       libavdevice    55.  3.100 / 55.  3.100
>       libavfilter     3. 87.100 /  3. 87.100
>       libswscale      2.  5.100 /  2.  5.100
>
>       libswresample   0. 17.103 /  0. 17.103
>     <tel:17.103%20%2F%C2%A0%200.%2017.103>
>       libpostproc    52.  3.100 / 52.  3.100
>     [x11grab @ 0x917dfc0] device: :1.0+0,0 -> display: :1.0 x: 0 y: 0
>     width: 1920 height: 1080
>     [x11grab @ 0x917dfc0] shared memory extension found
>     Input #0, x11grab, from ':1.0+0,0':
>       Duration: N/A, start: 1380208288.085940, bitrate: 1990656 kb/s
>         Stream #0:0: Video: rawvideo (BGR[0] / 0x524742), bgr0,
>     1920x1080, 1990656 kb/s, 30 tbr, 1000k tbn, 30 tbc
>
>     jack_port_get_latency_range called with an incorrect port 0
>     [jack @ 0x918e260] JACK client registered and activated
>     (rate=48000Hz, buffer_size=256 frames)
>
>     Guessed Channel Layout for  Input Stream #1.0 : stereo
>     Input #1, jack, from 'screencast':
>       Duration: N/A, start: 1380144319.409428, bitrate: 3072 kb/s
>
>         Stream #1:0: Audio: pcm_f32le, 48000 Hz, stereo, flt, 3072 kb/s
>     [swscaler @ 0x9171fc0] deprecated pixel format used, make sure you
>     did set range correctly
>
>     No pixel format specified, yuv444p for H.264 encoding chosen.
>     Use -pix_fmt yuv420p for compatibility with outdated media players.
>     -async is forwarded to lavfi similarly to -af
>     aresample=async=1:min_hard_comp=0.100000:first_pts=0.
>     [libx264 @ 0x95e97c0] using cpu capabilities: MMX2 SSE2Fast SSSE3
>     FastShuffle SSE4.2
>     [libx264 @ 0x95e97c0] profile High 4:4:4 Predictive, level 4.0,
>     4:4:4 8-bit
>     [libx264 @ 0x95e97c0] 64 - core 120 r2151 a3f4407 - H.264/MPEG-4
>     AVC codec - Copyleft 2003-2011 - http://www.videolan.org/x264.html
>     - options: cabac=0 ref=1 deblock=0:0:0 analyse=0:0 me=dia subme=0
>     psy=0 mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0
>     deadzone=21,11 fast_pskip=0 chroma_qp_offset=0 threads=6
>     sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0
>     constrained_intra=0 bframes=0 weightp=0 keyint=250 keyint_min=25
>     scenecut=0 intra_refresh=0 rc=cqp mbtree=0 qp=0
>     Output #0, matroska, to 'test.mkv':
>       Metadata:
>         encoder         : Lavf55.18.102
>         Stream #0:0: Video: h264 (libx264) (H264 / 0x34363248),
>     yuv444p, 1920x1080, q=-1--1, 1k tbn, 30 tbc
>
>         Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 48000
>     Hz, stereo, s16, 1536 kb/s
>     Stream mapping:
>       Stream #0:0 -> #0:0 (rawvideo -> libx264)
>       Stream #1:0 -> #0:1 (pcm_f32le -> pcm_s16le)
>     Press [q] to stop, [?] for help
>     [swscaler @ 0x9171fc0] Warning: data is not aligned! This can lead
>     to a speedloss
>     frame=   76 fps= 30 q=-1.0 Lsize=    1218kB time=00:00:02.53
>     bitrate=3939.6kbits/s
>     video:745kB audio:469kB subtitle:0 global headers:0kB muxing
>     overhead 0.358030%
>     [libx264 @ 0x95e97c0] frame I:1     Avg QP: 0.00 size:  7840
>     [libx264 @ 0x95e97c0] frame P:75    Avg QP: 0.00 size: 10057
>     [libx264 @ 0x95e97c0] mb I  I16..4: 100.0%  0.0%  0.0%
>     [libx264 @ 0x95e97c0] mb P  I16..4: 98.5%  0.0%  0.0% P16..4: 
>     0.0%  0.0%  0.0%  0.0%  0.0%    skip: 1.5%
>     [libx264 @ 0x95e97c0] coded y,u,v intra: 0.0% 0.0% 0.0% inter:
>     0.0% 0.0% 0.0%
>     [libx264 @ 0x95e97c0] i16 v,h,dc,p: 100%  0%  0%  0%
>     [libx264 @ 0x95e97c0] kb/s:2406.68
>     x at space:~/Documents/ffmpeg$
>
>
>     On 08/12/2013 03:18 AM, J. Liles wrote:
>>
>>
>>
>>     On Sun, Aug 11, 2013 at 6:18 AM, Diego Simak
>>     <diego.simak at gmail.com <mailto:diego.simak at gmail.com>> wrote:
>>
>>         2013/8/8 J. Liles <malnourite at gmail.com
>>         <mailto:malnourite at gmail.com>>
>>         >
>>         >
>>         > As some of you may recall, every time I've posted a demo
>>         video to LAD, I've had to include a disclaimer excusing the
>>         poor quality due to a lack of functional screencasting tools.
>>         >
>>         > Well, it took a couple of weeks of hair pulling and many,
>>         many hours of testing, but I finally arrived at a solution.
>>         >
>>         > Anyone who wants to create a screencast and record audio
>>         via JACK *in perfect sync* must do the following:
>>         >
>>         > Get ffmpeg. Apply this patch to it:
>>         >
>>         >
>>         https://github.com/original-male/FFmpeg/commit/d02509d04d396a98646ca81e9ba327a501486130.patch
>>         >
>>         > Build it with vorbis and h264 support.
>>         >
>>         > Then, start your favorite desktop environment. I use Xephyr
>>         for this.
>>         >
>>         > Have jack running (at -r 48000)
>>         >
>>         > Then run the following command:
>>         >
>>         > ffmpeg -fflags +genpts+igndts -f x11grab -vsync 0 -r 30 -s
>>         1920x1080 -i :${DISPLAY}.+0,0 -vcodec h264 -f jack -ac 2 -r:a
>>         48000  -i screencast -acodec pcm_s16le -r:v 30 -vsync 2
>>         -async 1 -map 0:0,1,0 -map 1:0 -preset ultrafast -qp 0 "$FILE"
>>         >
>>         > Where DISPLAY is the number of your X11 display and FILE is
>>         the filename for the screencast. I use a .mkv extension for
>>         the matroska container.
>>         >
>>         > Remember to connect the streams you want recorded to the
>>         'screencast' JACK inputs!
>>         >
>>         > With this setup I'm able to record a full 30 FPS @ 1080P
>>         with audio in perfect sync. Please share your results too.
>>         With some more evidence I might have a good case to get
>>         ffmpeg to accept my patch.
>>         >
>>         > Enjoy!
>>         >
>>         >
>>         >
>>         >
>>         >
>>         >
>>         >
>>         > _______________________________________________
>>         > Linux-audio-dev mailing list
>>         > Linux-audio-dev at lists.linuxaudio.org
>>         <mailto:Linux-audio-dev at lists.linuxaudio.org>
>>         > http://lists.linuxaudio.org/listinfo/linux-audio-dev
>>         >
>>
>>         My result:
>>
>>         - I had to change screen size to 1366x768 according to my
>>         laptop display
>>         - Audio and video are not in sync, I can see the following
>>         message
>>         after executing the ffmpeg command:
>>
>>         [swscaler @ 0x1ac5080] Warning: data is not aligned! This can
>>         lead to
>>         a speedloss
>>
>>
>>         This is the full log.
>>         Thank you very much!
>>
>>         diego at ruidosa:~$ ffmpeg -fflags +genpts+igndts -f x11grab
>>         -vsync 0 -r
>>         30 -s 1366x768 -i :0.0+0,0 -vcodec h264 -f jack -ac 2 -r:a
>>         48000  -i
>>         screencast -acodec pcm_s16le -r:v 30 -vsync 2 -async 1 -map
>>         0:0,1,0
>>         -map 1:0 -preset ultrafast -qp 0 aaa.mkv
>>         ffmpeg version N-55422-gb37ff48 Copyright (c) 2000-2013 the
>>         FFmpeg developers
>>           built on Aug 10 2013 10:54:00 with gcc 4.6 (Ubuntu/Linaro
>>         4.6.3-1ubuntu5)
>>           configuration: --enable-libx264 --enable-x11grab --enable-gpl
>>         --enable-libvorbis --disable-yasm
>>           libavutil      52. 41.100 / 52. 41.100
>>           libavcodec     55. 24.100 / 55. 24.100
>>           libavformat    55. 13.102 / 55. 13.102
>>           libavdevice    55.  3.100 / 55.  3.100
>>           libavfilter     3. 82.100 /  3. 82.100
>>           libswscale      2.  4.100 /  2.  4.100
>>           libswresample   0. 17.103 /  0. 17.103
>>         <tel:17.103%20%2F%20%C2%A00.%2017.103>
>>           libpostproc    52.  3.100 / 52.  3.100
>>         [x11grab @ 0x1ae3700] device: :0.0+0,0 -> display: :0.0 x: 0 y: 0
>>         width: 1366 height: 768
>>         [x11grab @ 0x1ae3700] shared memory extension found
>>         Input #0, x11grab, from ':0.0+0,0':
>>           Duration: N/A, start: 1376226919.464630, bitrate: 1007124 kb/s
>>             Stream #0:0: Video: rawvideo (BGR[0] / 0x524742), bgr0,
>>         1366x768,
>>         1007124 kb/s, 30 tbr, 1000k tbn, 30 tbc
>>         jack_port_get_latency_range called with an incorrect port 0
>>         [jack @ 0x1afbce0] JACK client registered and activated
>>         (rate=48000Hz,
>>         buffer_size=1024 frames)
>>         Guessed Channel Layout for  Input Stream #1.0 : stereo
>>         Input #1, jack, from 'screencast':
>>           Duration: N/A, start: 1376226919.619355, bitrate: 3072 kb/s
>>             Stream #1:0: Audio: pcm_f32le, 48000 Hz, stereo, flt,
>>         3072 kb/s
>>         [swscaler @ 0x1ac5080] deprecated pixel format used, make
>>         sure you did
>>         set range correctly
>>         No pixel format specified, yuv444p for H.264 encoding chosen.
>>         Use -pix_fmt yuv420p for compatibility with outdated media
>>         players.
>>         -async is forwarded to lavfi similarly to -af
>>         aresample=async=1:min_hard_comp=0.100000:first_pts=0.
>>         [libx264 @ 0x2b6e520] using cpu capabilities: MMX2 SSE2Fast SSSE3
>>         FastShuffle SSE4.1 Cache64
>>         [libx264 @ 0x2b6e520] profile High 4:4:4 Predictive, level
>>         3.2, 4:4:4 8-bit
>>         [libx264 @ 0x2b6e520] 64 - core 120 r2151 a3f4407 -
>>         H.264/MPEG-4 AVC
>>         codec - Copyleft 2003-2011 - http://www.videolan.org/x264.html -
>>         options: cabac=0 ref=1 deblock=0:0:0 analyse=0:0 me=dia
>>         subme=0 psy=0
>>         mixed_ref=0 me_range=16 chroma_me=1 trellis=0 8x8dct=0 cqm=0
>>         deadzone=21,11 fast_pskip=0 chroma_qp_offset=0 threads=3
>>         sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0
>>         constrained_intra=0 bframes=0 weightp=0 keyint=250 keyint_min=25
>>         scenecut=0 intra_refresh=0 rc=cqp mbtree=0 qp=0
>>         Output #0, matroska, to 'aaa.mkv':
>>           Metadata:
>>             encoder         : Lavf55.13.102
>>             Stream #0:0: Video: h264 (libx264) (H264 / 0x34363248),
>>         yuv444p,
>>         1366x768, q=-1--1, 1k tbn, 30 tbc
>>             Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001),
>>         48000 Hz,
>>         stereo, s16, 1536 kb/s
>>         Stream mapping:
>>           Stream #0:0 -> #0:0 (rawvideo -> libx264)
>>           Stream #1:0 -> #0:1 (pcm_f32le -> pcm_s16le)
>>         Press [q] to stop, [?] for help
>>         [swscaler @ 0x1ac5080] Warning: data is not aligned! This can
>>         lead to
>>         a speedloss
>>         frame=  122 fps= 23 q=-1.0 Lsize=  2774kB time=00:00:04.06
>>         bitrate=5588.3kbits/s
>>         video:2040kB audio:732kB subtitle:0 global headers:0kB muxing
>>         overhead 0.097703%
>>         [libx264 @ 0x2b6e520] frame I:1     Avg QP: 0.00  size:596863
>>         [libx264 @ 0x2b6e520] frame P:121   Avg QP: 0.00  size: 12324
>>         [libx264 @ 0x2b6e520] mb I  I16..4: 100.0%  0.0%  0.0%
>>         [libx264 @ 0x2b6e520] mb P  I16..4:  7.6%  0.0%  0.0%
>>          P16..4:  0.3%
>>         0.0%  0.0%  0.0%  0.0%    skip:92.1%
>>         [libx264 @ 0x2b6e520] coded y,u,v intra: 11.9% 37.1% 37.5%
>>         inter: 0.2% 0.2% 0.2%
>>         [libx264 @ 0x2b6e520] i16 v,h,dc,p: 91%  8%  0%  0%
>>         [libx264 @ 0x2b6e520] kb/s:4107.72
>>         Received signal 2: terminating.
>>         diego at ruidosa:~$
>>         diego at ruidosa:~$
>>         diego at ruidosa:~$
>>
>>
>>
>>     Interesting. If you use Xephyr you can record a virtual desktop
>>     larger than your actual display (and therefore 1920x1080), does
>>     that avoid the error (and give you better results)?
>>
>>
>>
>>     _______________________________________________
>>     Linux-audio-dev mailing list
>>     Linux-audio-dev at lists.linuxaudio.org  <mailto:Linux-audio-dev at lists.linuxaudio.org>
>>     http://lists.linuxaudio.org/listinfo/linux-audio-dev
>
>
>
>  What is the output of jack_lsp -l?
>

x at space:~$ jack_lsp -l
system:capture_1
     port latency = 256 frames
     port playback latency = [ 0 0 ] frames
     port capture latency = [ 256 256 ] frames
system:capture_2
     port latency = 256 frames
     port playback latency = [ 0 0 ] frames
     port capture latency = [ 256 256 ] frames
system:playback_1
     port latency = 768 frames
     port playback latency = [ 768 768 ] frames
     port capture latency = [ 0 0 ] frames
system:playback_2
     port latency = 768 frames
     port playback latency = [ 768 768 ] frames
     port capture latency = [ 0 0 ] frames
screencast:input_1
     port latency = 0 frames
     port playback latency = [ 0 0 ] frames
     port capture latency = [ 256 256 ] frames
screencast:input_2
     port latency = 0 frames
     port playback latency = [ 0 0 ] frames
     port capture latency = [ 256 256 ] frames
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