Recherche avancée

Sur d’autres sites (4826)

• avformat/matroskaenc : Avoid seek when writing Cues at the front

  29 décembre 2019, par Andreas Rheinhardt

  avformat/matroskaenc : Avoid seek when writing Cues at the front
  When the Cues are written in front of the Cluster, the muxer would seek
  
  to the beginning (to where the Cues ought to be written) and write the
  
  Cues ; afterwards it would seek back to the end of the file only to seek
  
  to the beginning once again to update several elements there. This
  
  commit removes the seek to the end.
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
  

  • [DH] libavformat/matroskaenc.c

• avformat/matroskaenc : Fix edge case of writing Cues at the beginning

  28 décembre 2019, par Andreas Rheinhardt

  avformat/matroskaenc : Fix edge case of writing Cues at the beginning
  The Matroska muxer has the ability to write the Cues (the index) at the
  
  beginning of the file (in front of the Cluster) : The user inputs the
  
  amount of space that should be reserved at the beginning of the file and
  
  if this is sufficient, the Cues will be written there and the part of the
  
  reserved space not used up by the Cues will be filled with a "Void"
  
  element.
  There is just one problem with this : One can not fill a single byte this
  
  way, because said Void element is minimally two bytes long (one byte ID,
  
  one byte length field). Up until now, if one reserved one byte more than
  
  needed, one would run into an assert when writing the Void element.
  There are two solutions for this : Error out if it happens. Or adjust the
  
  length field of the Cues in order to ensure that the above situation
  
  can't happen (i.e. write the length on one byte more than necessary).
  
  The first solution is very unsatisfactory, as enough space has been
  
  reserved. Therefore this commit implements the second solution.
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
  

  • [DH] libavformat/matroskaenc.c

• CLI Extract date/time stamp (timestamp) from quicktime or mpeg files

  25 mai 2020, par vy32

  Is there a way to extract a date/time or a timestamp from various multi-media container files with Quicktime or MPEG2/MPEG4 ? I'm looking ideally for a command line tool. I have been able to get timestamps using ffprobe, part of the ffmpeg suite, but I haven't gotten the year, month and date. The camera had a clock so I'm pretty sure that this information was available.

  



  The history of this data file is that it was first shot on miniDV and transferred to a Mac over Firewire 800 using QuicktimePlayer to record the video. I'm told that the miniDV format is motion jpeg. The file command reports that the file is ISO Media, Apple QuickTime movie, Apple QuickTime (.MOV/QT).

  



  % ffprobe -f lavfi -i "movie=filename.mov,fps=fps=25[out0]" -show_frames -show_streams -show_entries frame=pkt_pts_time -of csv=p=0 2>&1 | head -30
ffprobe version 4.2.2 Copyright (c) 2007-2019 the FFmpeg developers
  built with Apple clang version 11.0.0 (clang-1100.0.33.17)
  configuration: --prefix=/opt/local --enable-swscale --enable-avfilter --enable-avresample --enable-libmp3lame --enable-libvorbis --enable-libopus --enable-librsvg --enable-libtheora --enable-libopenjpeg --enable-libmodplug --enable-libvpx --enable-libsoxr --enable-libspeex --enable-libass --enable-libbluray --enable-lzma --enable-gnutls --enable-fontconfig --enable-libfreetype --enable-libfribidi --disable-libjack --disable-libopencore-amrnb --disable-libopencore-amrwb --disable-libxcb --disable-libxcb-shm --disable-libxcb-xfixes --disable-indev=jack --enable-opencl --disable-outdev=xv --enable-audiotoolbox --enable-videotoolbox --enable-sdl2 --disable-securetransport --mandir=/opt/local/share/man --enable-shared --enable-pthreads --cc=/usr/bin/clang --arch=x86_64 --enable-x86asm --enable-libx265 --enable-gpl --enable-postproc --enable-libx264 --enable-libxvid --enable-nonfree --enable-libfdk-aac
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
  libpostproc    55.  5.100 / 55.  5.100
Input #0, lavfi, from 'movie=/Volumes/SanDiskSSD/Movies/Italy22.mov,fps=fps=25[out0]':
  Duration: N/A, start: 0.000000, bitrate: N/A
    Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 640x480 [SAR 1:1 DAR 4:3], 25 tbr, 25 tbn, 25 tbc
0.000000
0.040000
0.080000
0.120000
0.160000
0.200000
0.240000
0.280000
0.320000
0.360000
0.400000
0.440000
0.480000
0.520000
0.560000
%


  



  I want output showing the year, month and date that this was shot.