Sur d’autres sites (5628)

• Record UDP stream with ffmpeg video+klv-data

  26 septembre 2017, par mfreiholz

  I’d like to record an MPEGTS UDP stream with ffmpeg binary to disk.

  This works in a stable network :

  ffmpeg.exe -i "udp://224.10.10.10:15006?multicast=1&timeout=360000000&reuse=1" -f mpegts -map 0:0? -map 0:1? -map 0:2? -c copy "C:/test.ts"

  The entire stream is saved to test.ts.

  Live Environment

  In my live environment it is possible that the connection is very bad or is not available at all (cable disconnect, device reboot, ...) for a few minutes. I want ffmpeg to simply continue writing upcoming frames to *.ts file. I don’t need the lost frames.

  Currently the following errors appears, if there was a too long brake between UDP frames :

  [mpegts @ 00000000003cf920] Application provided invalid, non monotonically increasing dts to muxer in stream 1: 11606399 >= 2084534
  
  av_interleaved_write_frame(): Invalid argument

  It looks like to be a problem with the timestamp. My idea would be to tell FFMPEG to ignore those errors and simply continue.

  Is it even possible with the ffmpeg binary or do I have to solve the problem with a custom C/C++ implementation using the library ?

  Thank you

  Update 1

  If I only record the video stream -map 0:0? and not the others it seems to work. Looks like the problem is associated with the second stream (No.1) which is KLV encoded data.

• Record only audio using ffmpeg commands in OSX Terminal

  27 septembre 2017, par Swati

  I have tried multiple commands, the file is created but no audio.

  ffmpeg -f avfoundation -framerate 30 -i "Built In Input" -acodec aac -ab 64000 -ar 48000 -ac 2 -f flv test.wav
  
  
  
  ffmpeg -f avfoundation -i ":Built In Input" -acodec libmp3lame -ab 32k -ac 1 -f flv test.wav
  
  
  
  ffmpeg -f avfoundation -i ":1" -r 25  -c:v libx264 -preset fast -crf 22 -c:a libfdk_aac  -b:a 128k -ar 44100 -s 640x480  test.mp4
  
  
  
  ffmpeg -f avfoundation -i ":1" -acodec libmp3lame -ab 32k -ac 1 -f mp3 swati.mp3
  
  
  
  
  
  
  
  
  
  ffmpeg -f avfoundation -framerate 30 -i ":1" -ab 128000 -ac 2 -f flv /Users/admin/Documents/swati.flv

  Result in terminal :
  video:0kB audio:686kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead : 0.810823%

  Above line indicates audio exists but i cant hear anything
  any suggestions what should I do ?

• FFmpeg 3.3.4 avfoundation to record only a specific section of the screen on macOS Sierra using the command line

  16 octobre 2017, par antedesk

  I’m using FFmpeg version 3.3.4 (installed via brew) through the command line to record my desktop during some automated tests on my macOS Sierra (10.12.6).

  I would like to record only a specific section of the screen but, unfortunately, I’m not able to find the proper options in the documentation to reach my goal.

  According to the FFmpeg documentation for avfoundation, this is the command I use :

  ffmpeg 
  
  -f avfoundation    // avfoundation
  
  -pix_fmt uyvy422   // pixel format
  
  -i 1               // input: desktop
  
  -r 30              // framerate for output
  
  [PATH]/test.mp4      // filename

  When I run this command I have the following output :

  ffmpeg version 3.3.4 Copyright (c) 2000-2017 the FFmpeg developers
  
    built with Apple LLVM version 9.0.0 (clang-900.0.37)
  
    configuration: --prefix=/usr/local/Cellar/ffmpeg/3.3.4 --enable-shared --enable-pthreads --enable-version3 --enable-hardcoded-tables --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-gpl --enable-ffplay --enable-frei0r --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-opencl --enable-videotoolbox --enable-openssl --disable-lzma --enable-libopenjpeg --disable-decoder=jpeg2000 --extra-cflags=-I/usr/local/Cellar/openjpeg/2.3.0/include/openjpeg-2.3 --enable-nonfree --enable-vda
  
    libavutil      55. 58.100 / 55. 58.100
  
    libavcodec     57. 89.100 / 57. 89.100
  
    libavformat    57. 71.100 / 57. 71.100
  
    libavdevice    57.  6.100 / 57.  6.100
  
    libavfilter     6. 82.100 /  6. 82.100
  
    libavresample   3.  5.  0 /  3.  5.  0
  
    libswscale      4.  6.100 /  4.  6.100
  
    libswresample   2.  7.100 /  2.  7.100
  
    libpostproc    54.  5.100 / 54.  5.100
  
  [avfoundation @ 0x7fb7d4005800] Stream #0: not enough frames to estimate rate; consider increasing probesize
  
  Input #0, avfoundation, from '1':
  
    Duration: N/A, start: 7263.782833, bitrate: N/A
  
      Stream #0:0: Video: rawvideo (UYVY / 0x59565955), uyvy422, 1920x1080, 1000k tbr, 1000k tbn, 1000k tbc
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo (native) -> h264 (libx264))
  
  Press [q] to stop, [?] for help
  
  No pixel format specified, yuv422p for H.264 encoding chosen.
  
  Use -pix_fmt yuv420p for compatibility with outdated media players.
  
  [libx264 @ 0x7fb7d4028400] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
  
  [libx264 @ 0x7fb7d4028400] profile High 4:2:2, level 4.0, 4:2:2 8-bit
  
  [libx264 @ 0x7fb7d4028400] 264 - core 148 r2795 aaa9aa8 - H.264/MPEG-4 AVC codec - Copyleft 2003-2017 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
  
  Output #0, mp4, to '[PATH]/test.mp4':
  
    Metadata:
  
      encoder         : Lavf57.71.100
  
      Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv422p, 1920x1080, q=-1--1, 30 fps, 15360 tbn, 30 tbc
  
      Metadata:
  
        encoder         : Lavc57.89.100 libx264
  
      Side data:
  
        cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
  
  frame=   83 fps= 28 q=-1.0 Lsize=     525kB time=00:00:02.66 bitrate=1612.6kbits/s dup=1 drop=0 speed=0.889x

  I tried to use the -video_size option to set the video frame size, but it doesn’t work.