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• FFMPEG add audio to a video but clip it to the video length

  5 novembre 2011, par Daniel Lloyd-Wood

  I'm trying to create a video from an image sequence and add audio with FFMPEG

  The frame sequence is only 25 frames long but the audio is several minutes. I want FFMPEG to clip the audio to the length of the frame sequence.

  This is the command I have tried:

  ffmpeg -i input_images%04d.jpg -pix_fmt yuv420p -vcodec mjpeg -qmin 1 -qmax 1 -r 25 -i audio_file.mp3 -ar 22050 -ab 192k -aframes 25 output.mov
  

  This results in a video with the first image sequence but the full length audio. -aframes is ignored. Any ideas?

• Add audio (with an offset) to video with FFMPEG

  5 novembre 2011, par slotishtype

  I have a 10 minute video and a 50 minute audio mp3. The video starts at 500 seconds into the audio. Using FFMPEG, how can I add the the audio to the video but specify a 500 seconds audio offset (So that they sync up)?

  EDIT:::::

  Down the bottom of this page it suggests how to specify an offset.

  $ ffmpeg -i video_source -itsoffet delay -i audio_source -map 0:x -map 1:y ......

  However, when I apply this, it still starts the audio from the start.

  Thanks

• Encoding graphics into an mpeg stream

  5 novembre 2011, par eshalev

  looking for an example of how to programatically encode a frame-buffer into an mpeg stream. I need this to experiment with some mpeg encoders, to see how different patterns compress.

  I have a slight inclination towards Windows, although if linux gives some advantage it is not a problem.

• Elimination compression from videos generated from images using ffmpeg ?

  5 novembre 2011, par Magz

  So I'm using ffmpeg to generate videos from a series of images. Unfortunately every video I've generated so far becomes compressed about halfway through (these are about 10-30 second videos). I've tried a lot of different options, but here's an example and the resulting output.

  Any suggestions?

  ffmpeg -minrate 5000k -maxrate 5000k -bufsize 1835k -b 5000k -s 480x480 \
  -f image2 -r 10 -i 'dms-%05d.jpeg' output.flv
  
  
  ffmpeg version 0.8.1, Copyright (c) 2000-2011 the FFmpeg developers
    built on Jul 29 2011 14:13:56 with gcc 4.2.1 (Apple Inc. build 5664)
    configuration: --enable-libmp3lame --enable-shared --disable-mmx --arch=x86_64
    libavutil    51.  9. 1 / 51.  9. 1
    libavcodec   53.  7. 0 / 53.  7. 0
    libavformat  53.  4. 0 / 53.  4. 0
    libavdevice  53.  1. 1 / 53.  1. 1
    libavfilter   2. 23. 0 /  2. 23. 0
    libswscale    2.  0. 0 /  2.  0. 0
  [image2 @ 0x101007c00] max_analyze_duration 5000000 reached at 5000000
  Input #0, image2, from 'dms-%05d.jpeg':
    Duration: 00:00:10.00, start: 0.000000, bitrate: N/A
      Stream #0.0: Video: mjpeg, yuvj444p, 559x480 [PAR 1:1 DAR 559:480], 10 fps, 10 tbr, 10 tbn, 10 tbc
  Incompatible pixel format 'yuvj444p' for codec 'flv', auto-selecting format 'yuv420p'
  [buffer @ 0x100d00230] w:559 h:480 pixfmt:yuvj444p tb:1/1000000 sar:1/1 sws_param:
  [buffersink @ 0x100d02160] auto-inserting filter 'auto-inserted scaler 0' between the filter 'src' and the filter 'out'
  [scale @ 0x100d023a0] w:559 h:480 fmt:yuvj444p -> w:559 h:480 fmt:yuv420p flags:0x4
  Output #0, flv, to 'output.flv':
    Metadata:
      encoder         : Lavf53.4.0
      Stream #0.0: Video: flv, yuv420p, 559x480 [PAR 1:1 DAR 559:480], q=2-31, 200 kb/s, 1k tbn, 10 tbc
  Stream mapping:
    Stream #0.0 -> #0.0
  Press [q] to stop, [?] for help
  [buffer @ 0x100d00230] Buffer video input changed from size:559x480 fmt:yuvj444p to size:480x480 fmt:yuvj420p
  [scale @ 0x100d023a0] w:480 h:480 fmt:yuvj420p -> w:559 h:480 fmt:yuv420p flags:0x2
  [buffer @ 0x100d00230] Buffer video input changed from size:480x480 fmt:yuvj420p to size:559x480 fmt:yuvj444p
  [scale @ 0x100d023a0] w:559 h:480 fmt:yuvj444p -> w:559 h:480 fmt:yuv420p flags:0x2
  [buffer @ 0x100d00230] Buffer video input changed from size:559x480 fmt:yuvj444p to size:480x480 fmt:yuvj420p
  [scale @ 0x100d023a0] w:480 h:480 fmt:yuvj420p -> w:559 h:480 fmt:yuv420p flags:0x2
  [buffer @ 0x100d00230] Buffer video input changed from size:480x480 fmt:yuvj420p to size:559x480 fmt:yuvj444p
  [scale @ 0x100d023a0] w:559 h:480 fmt:yuvj444p -> w:559 h:480 fmt:yuv420p flags:0x2
  [buffer @ 0x100d00230] Buffer video input changed from size:559x480 fmt:yuvj444p to size:480x480 fmt:yuvj420p
  [scale @ 0x100d023a0] w:480 h:480 fmt:yuvj420p -> w:559 h:480 fmt:yuv420p flags:0x2
  [buffer @ 0x100d00230] Buffer video input changed from size:480x480 fmt:yuvj420p to size:559x480 fmt:yuvj444p
  [scale @ 0x100d023a0] w:559 h:480 fmt:yuvj444p -> w:559 h:480 fmt:yuv420p flags:0x2
  frame=  100 fps= 35 q=24.8 Lsize=    1062kB time=00:00:10.00 bitrate= 870.2kbits/s    
  video:1060kB audio:0kB global headers:0kB muxing overhead 0.166586%
  

• Getting either incorrect output resolution or FPS from ffmpeg

  5 novembre 2011, par Adam

  I am capturing an RTSP stream from a security camera, and transcoding it for (live streaming) to iphone, using OSX as the encoding platform. I have it working correctly, and Im tuning it. However, it seems that it is not outputting the requested resolution. This is my script

  /Applications/SecurityCamera/openRTSP -v -c -t rtsp://10.0.1.118/ch1-s1 | \
      /Applications/SecurityCamera/ffmpeg \
      -r 10 -i - \
      -y -an -ab 64000 -f mpegts -vcodec copy -s 960x640 \
      -flags +loop -cmp +chroma -partitions +parti4x4+partp8x8+partb8x8 \
      -subq 5 -trellis 1 -refs 1 -coder 0 -me_range 16  -keyint_min 25 \
      -sc_threshold 40 -i_qfactor 0.71 -bt 400k -maxrate 524288 -bufsize 524288 \
      -qcomp 0.6 -qmin 10 -qmax 51 -qdiff 4 -level 30 \
      -aspect 960:640 -r 10 -g 10 -async 2 -\
      |/Applications/SecurityCamera/mediastreamsegmenter -b http://localhost:8080/\
        -f /Library/WebServer/Documents/ -i stream.m3u8 -t 10 -s 4 -D
  

  This is the status report:

  Input #0, h264, from 'pipe:':
  
    Duration: N/A, bitrate: N/A
    Stream #0.0: Video: h264, yuv420p, 1600x1200, 10 fps, 10 tbr, 1200k tbn, 20 tbc
    [mpegts @ 0x10100c200] muxrate VBR, pcr every 1 pkts, sdt every 200, pat/pmt every 40 pkts
    Output #0, mpegts, to 'pipe:':
    Metadata:
      encoder         : Lavf52.93.0
      Stream #0.0: Video: libx264, yuv420p, 1600x1200 [PAR 1:1 DAR 4:3], q=2-31, 90k tbn, 10 tbc
  Stream mapping:
    Stream #0.0 -> #0.0
  

  You can see that its working, but it is outputting 1600x1200 for some reason. (possibly -vcodec copy copies all codec parameters, not just the codec type?)

  If I change the -vcodec copy to -vcodec libx264 then I get the correct status report (stating 960x640, correct), but the streaming switches to 2 FPS (why? Im forcing both input and output!) and it halts after 54 frames (see output below)

  Seems stream 0 codec frame rate differs from container frame rate: 20.00 (20/1) -> 10.00 (20/2)
  Input #0, h264, from 'pipe:':
    Duration: N/A, bitrate: N/A
      Stream #0.0: Video: h264, yuv420p, 1600x1200, 10 fps, 10 tbr, 1200k tbn, 20 tbc
  [buffer @ 0x100d02420] w:1600 h:1200 pixfmt:yuv420p
  [scale @ 0x100d026f0] w:1600 h:1200 fmt:yuv420p -> w:960 h:640 fmt:yuv420p flags:0x4
  [libx264 @ 0x10100d400] using SAR=1/1
  [libx264 @ 0x10100d400] frame MB size (60x40) > level limit (1620)
  [libx264 @ 0x10100d400] using cpu capabilities: MMX2 SSE2Fast SSSE3 Cache64 SlowCTZ SlowAtom
  [libx264 @ 0x10100d400] profile Constrained Baseline, level 3.0
  [mpegts @ 0x10100c200] muxrate VBR, pcr every 1 pkts, sdt every 200, pat/pmt every 40 pkts
  Output #0, mpegts, to 'pipe:':
    Metadata:
      encoder         : Lavf52.93.0
      Stream #0.0: Video: libx264, yuv420p, 960x640 [PAR 1:1 DAR 3:2], q=10-51, 200 kb/s, 90k tbn, 10 tbc
  Stream mapping:
    Stream #0.0 -> #0.0
  read pmap fffps=  3 q=37.0 size=      37kB time=0.10 bitrate=3008.0kbits/s    bits/s    
  video pid set at 100
  found sequence start
    next segment value 1026000
  written bytes 376 skipped 0
  frame=   54 fps=  2 q=-1.0 Lsize=     160kB time=5.40 bitrate= 242.0kbits/s    
  video:141kB audio:0kB global headers:0kB muxing overhead 12.872737%
  frame I:6     Avg QP:34.68  size: 23524
  [libx264 @ 0x10100d400] frame P:48    Avg QP:41.53  size:    75
  [libx264 @ 0x10100d400] mb I  I16..4: 63.9%  0.0% 36.1%
  [libx264 @ 0x10100d400] mb P  I16..4:  0.1%  0.0%  0.0%  P16..4:  0.8%  0.1%  0.0%  0.0%  0.0%    skip:99.0%
  [libx264 @ 0x10100d400] final ratefactor: 38.54
  [libx264 @ 0x10100d400] coded y,uvDC,uvAC intra: 57.7% 22.3% 2.0% inter: 0.0% 0.1% 0.0%
  [libx264 @ 0x10100d400] i16 v,h,dc,p: 23% 35% 27% 15%
  [libx264 @ 0x10100d400] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 23% 32% 16%  4%  3%  3%  7%  4%  8%
  [libx264 @ 0x10100d400] i8c dc,h,v,p: 83% 11%  5%  0%
  [libx264 @ 0x10100d400] kb/s:214.43