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• configure Xuggler on Ubuntu 14-04

  22 juillet 2015, par Aida

  I was trying to install Xuggle on Ubuntu with this tutorial

  But when I used ant stage it doesn`t work. I see these commands on the terminal

  > root@test1:~# ant stage Unable to locate tools.jar. Expected to find
  
  > it in /usr/lib/jvm/java-7-openjdk-amd64/lib/tools.jar Buildfile:
  
  > build.xml does not exist! Build failed

  Do you have any idea how I can fix it ?

• Why is ffmpeg start time non-zero in .ts format ?

  22 janvier 2014, par geekydel

  I'm using ffmpeg to transcode video to .ts format, and I am getting unexpected start times in the output file.

  To simplify things, I've started with a nice simple AVI file (no audio) :

  ffmpeg -i in.avi 
  
  ...
  
  Input #0, avi, from 'in.avi':
  
    Metadata:
  
      encoder         : Lavf55.25.100
  
    Duration: 00:00:05.00, start: 0.000000, bitrate: 448 kb/s
  
      Stream #0:0: Video: mpeg4 (Simple Profile) (FMP4 / 0x34504D46), yuv420p, 480x270 [SAR 1:1 DAR 16:9], 24 tbr, 24 tbn, 24 tbc

  Duration=5s, startTime=0s, as expected.

  However, if I transcode to .ts file, with no customisation :

  ffmpeg -i in.avi -y out.ts
  
  ...
  
  Input #0, avi, from 'in.avi':
  
    Metadata:
  
      encoder         : Lavf55.25.100
  
    Duration: 00:00:05.00, start: 0.000000, bitrate: 448 kb/s
  
      Stream #0:0: Video: mpeg4 (Simple Profile) (FMP4 / 0x34504D46), yuv420p, 480x270 [SAR 1:1 DAR 16:9], 24 tbr, 24 tbn, 24 tbc
  
  Output #0, mpegts, to 'out.ts':
  
    Metadata:
  
      encoder         : Lavf55.25.100
  
      Stream #0:0: Video: mpeg2video, yuv420p, 480x270 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 90k tbn, 24 tbc
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (mpeg4 -> mpeg2video)
  
  Press [q] to stop, [?] for help
  
  frame=  120 fps=0.0 q=31.0 Lsize=     315kB time=00:00:04.95 bitrate= 519.9kbits/s dup=1 drop=0    
  
  video:277kB audio:0kB subtitle:0 global headers:0kB muxing overhead 13.491544%

  Then I get a very odd parameters (Duration=4:96s, startTime=1.441667) :

  ffmpeg -i out.ts
  
  ...
  
  Input #0, mpegts, from 'out.ts':
  
    Duration: 00:00:04.96, start: 1.441667, bitrate: 519 kb/s
  
    Program 1 
  
      Metadata:
  
        service_name    : Service01
  
        service_provider: FFmpeg
  
      Stream #0:0[0x100]: Video: mpeg2video (Main) ([2][0][0][0] / 0x0002), yuv420p(tv), 480x270 [SAR 1:1 DAR 16:9], max. 104857 kb/s, 24 fps, 24 tbr, 90k tbn, 48 tbc

  Now, I can just about understand why the transcode might lose a couple of frames, which explains the duration, but I can't see why the start time should be any different to the AVI file's start time.

  I have tried transcoding to .mp4, .webm and .mov, and in each case we get the 'correct' start time of 0.0s. Can anybody help explain why .ts files behave differently ?

  Thanks in advance !

  (ffmpeg version information :)

  ffmpeg version N-60031-ga459891 Copyright (c) 2000-2014 the FFmpeg developers
  
    built on Jan 21 2014 05:31:54 with gcc 4.6 (Debian 4.6.3-1)
  
    configuration: --prefix=/root/ffmpeg-static/64bit --extra-cflags='-I/root/ffmpeg-static/64bit/include -static' --extra-ldflags='-L/root/ffmpeg-static/64bit/lib -static' --extra-libs='-lxml2 -lexpat -lfreetype' --enable-static --disable-shared --disable-ffserver --disable-doc --enable-bzlib --enable-zlib --enable-postproc --enable-runtime-cpudetect --enable-libx264 --enable-gpl --enable-libtheora --enable-libvorbis --enable-libmp3lame --enable-gray --enable-libass --enable-libfreetype --enable-libopenjpeg --enable-libspeex --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-version3 --enable-libvpx
  
    libavutil      52. 63.100 / 52. 63.100
  
    libavcodec     55. 48.102 / 55. 48.102
  
    libavformat    55. 25.100 / 55. 25.100
  
    libavdevice    55.  5.102 / 55.  5.102
  
    libavfilter     4.  1.100 /  4.  1.100
  
    libswscale      2.  5.101 /  2.  5.101
  
    libswresample   0. 17.104 /  0. 17.104
  
    libpostproc    52.  3.100 / 52.  3.100

• Raspberry Pi : how to configure audio sampling rate in ALSA, ffmpeg, mp3 encoding pipeline

  30 janvier 2014, par user3252022

  I have a Pi with the camera module and a USB sound card. The intent is to use this combination to generate the MPEG2-TS segments for HTTP Live Streaming (Apple's HLS.)

  raspivid -ih -e -w 1280 -h 720 -fps 25 -vf -hf -t 0 -b 1800000 -o - | \
  
  ffmpeg -y \
  
    -i - \
  
    -ac 1 \
  
    -f alsa -ar 22050 -i hw:0,0 \
  
    -c:v copy \
  
    -c:a libshine -strict -2 \
  
    -map 0:0 -map 1:0 \
  
    -f ssegment \
  
    -segment_list_entry_prefix live/ \
  
    -segment_time 10 \
  
    -segment_format mpegts \
  
    -segment_list "$base/live.m3u8" \
  
    -segment_list_size 20 \
  
    -segment_list_flags +live \
  
    -segment_list_type m3u8 \
  
    -segment_wrap 200 \
  
    live/%08d.ts"

  The above basically works. The heavy lifting of H.264 video encoding is done in hardware. However, MP3 encoding in software brings the ARM core to its knees. The option :

  -f alsa -ar 22050 -i hw:0,0

  is intended to lighten the CPU loading by reducing the ALSA audio sampling rate - from the 48kHz default down to 22.05kHz. The sampling rate, however, won't budge to anything below 44.1kHz.

  Any idea what I'm doing wrong ? Why can't I tell ALSA to sample at 22.05kHz (or 8kHz for that matter ?)

  Here's an excerpt output from running the encoding pipeline :

  ffmpeg version N-60125-g4b8c599 Copyright (c) 2000-2014 the FFmpeg developers
  
    built on Jan 29 2014 10:16:02 with gcc 4.6 (Debian 4.6.3-14+rpi1)
  
    configuration: --enable-gpl --enable-nonfree --enable-libshine
  
    ...   
  
  Input #0, h264, from 'pipe:':
  
    Duration: N/A, bitrate: N/A
  
      Stream #0:0: Video: h264 (High), yuv420p, 1280x720, 25 fps, 25 tbr, 1200k tbn, 50 tbc
  
  Guessed Channel Layout for  Input Stream #1.0 : mono
  
  Input #1, alsa, from 'hw:0,0':
  
    Duration: N/A, start: 1391066215.835499, bitrate: 705 kb/s
  
      Stream #1:0: Audio: pcm_s16le, 44100 Hz, mono, s16, 705 kb/s
  
      ...