2013/8/8 J. Liles <malnourite@xxxxxxxxx> > > > 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@xxxxxxxxxxxxxxxxxxxx > 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@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 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@ruidosa:~$ diego@ruidosa:~$ diego@ruidosa:~$ _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
