Sur d’autres sites (7057)

• for loop from two values in list of dicts with python and ffmpeg

  30 décembre 2019, par Brendon Rathbone

  I’m having an issue figuring out how to do the last for loop in my first really useful python program. I am trying to split a video with ffmpeg based on a bunch of logic to figure out edit points.

  I have a list of dictionaries ’cut_list’ that I have sorting figured out like this

  [{'Cutstart': '01:00:00:00', 'CutEnd': '01:00:05:00'}, {'Cutstart': '01:00:10:01', 'CutEnd': '01:00:15:00'}, {'Cutstart': '01:00:20:01', 'CutEnd': '01:00:25:01'}]

  I then am trying to feed these values to ffmpeg, iterating over the list of dicts like so :

  cutcounter=1
  
  for Cutstart & CutEnd in cut_list:
  
      for k in Cutstart.items() & v in CutEnd.items() :
  
          print(k)
  
          print(v)
  
          intime=Timecode(fps_real, k)
  
          intime.set_fractional(True)
  
          outtime=Timecode(fps_real, v)
  
          outtime.set_fractional(True)
  
          cutfile=str(cutcounter)+".mxf"
  
          print(k)
  
          print(v)
  
          subprocess.call(['ffmpeg', '-i', "C:\\path\\to\\file\\BaseFile.mxf", '-ss', k, '-to', v, '-c:v', 'copy', '-c:a', 'copy', cutfile])
  
          cutcounter=cutcounter+1

  My expected output is to iterate over the list and have chunks of the video split off at those specific timecodes and numbered 1.mxf and count up for every for loop to be recombined with inserted fixes to those timespans. I think after I figure out the for loop I will need to also feed the timecode values as HH:mm:ss:mss instead of HH:mm:ss:ff but that’s not the part that I’m having trouble figuring out yet. Right now I just can’t grok the logic of getting the cutstart and cutend for each timecode to feed into the ffmpeg script.

  Current error as I bash my head against the wall trying to get smarter is : Syntax Error: cannot assign to operator

  I’m definitely inexperienced and have hacked this together from a lot of other helpful posts, but am struggling with sorting and lists vs list of dicts vs tuples etc. and where and when to use each one.

• Inputing a List of Files for Concatenation with Node.js Module fluent-ffmpeg

  26 juin 2018, par carpiediem

  Version information

  • fluent-ffmpeg version : 2.1.2
  • ffmpeg version : 3.4.2
  • OS : Windows 10

  Code to reproduce

  ffmpeg('C:/path/to/list.txt').mergeToFile('C:/path/to/out.mp4', 'C:/path/to/temp');

  list.txt :

  file 'C:/path/to/chunk01.ts'
  
  file 'C:/path/to/chunk02.ts'
  
  file 'C:/path/to/chunk03.ts'
  
  file 'C:/path/to/chunk04.ts'

  Note : I’ve tried both absolute and relative paths, with the same result.

  Expected results

  A video file at C:/path/to/out.mp4 that matches the 4 files in list.txt, concatenated end-to-end.

  Observed results

  An empty file at C:/path/to/out.mp4 with 0 duration and only 15kB in size. No errors were thrown.

  This is the command that I’m trying to duplicate (it works as expected, with relative paths in list.txt) :

  C:/path/to> ffmpeg -f concat -i list.txt -c copy out.ts

  stdout & stderr

  stdout was empty. stderr is copied below (with file names modified to match the ones above) :

  ffmpeg version 3.4.2 Copyright (c) 2000-2018 the FFmpeg developers
  
    built with gcc 7.3.0 (GCC)
  
    configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-bzlib --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libmfx --enable-cuda --enable-cuvid --enable-d3d11va --enable-nvenc --enable-dxva2 --enable-avisynth
  
    libavutil      55. 78.100 / 55. 78.100
  
    libavcodec     57.107.100 / 57.107.100
  
    libavformat    57. 83.100 / 57. 83.100
  
    libavdevice    57. 10.100 / 57. 10.100
  
    libavfilter     6.107.100 /  6.107.100
  
    libswscale      4.  8.100 /  4.  8.100
  
    libswresample   2.  9.100 /  2.  9.100
  
    libpostproc    54.  7.100 / 54.  7.100
  
  Input #0, tty, from 'C:/path/to/list.txt':
  
    Duration: 00:00:00.08, bitrate: 42 kb/s
  
      Stream #0:0: Video: ansi, pal8, 640x400, 25 fps, 25 tbr, 25 tbn, 25 tbc
  
  Stream mapping:
  
    Stream #0:0 (ansi) -> concat
  
    concat -> Stream #0:0 (libx264)
  
  Press [q] to stop, [?] for help
  
  [libx264 @ 000001e385b45040] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
  
  [libx264 @ 000001e385b45040] profile High 4:4:4 Predictive, level 3.0, 4:4:4 8-bit
  
  [libx264 @ 000001e385b45040] 264 - core 155 r2901 7d0ff22 - H.264/MPEG-4 AVC codec - Copyleft 2003-2018 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x1:0x111 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=4 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 'C:/path/to/out.mp4':
  
    Metadata:
  
      encoder         : Lavf57.83.100
  
      Stream #0:0: Video: h264 (libx264) (avc1 / 0x31637661), yuv444p, 640x400, q=-1--1, 25 fps, 12800 tbn, 25 tbc
  
      Metadata:
  
        encoder         : Lavc57.107.100 libx264
  
      Side data:
  
        cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: -1
  
  frame=    2 fps=0.0 q=-1.0 Lsize=      15kB time=00:00:00.04 bitrate=3099.0kbits/s speed=1.55x
  
  video:14kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 5.619430%
  
  [libx264 @ 000001e385b45040] frame I:1     Avg QP:12.71  size:  8083
  
  [libx264 @ 000001e385b45040] frame P:1     Avg QP:29.71  size:  5928
  
  [libx264 @ 000001e385b45040] mb I  I16..4: 87.9%  0.0% 12.1%
  
  [libx264 @ 000001e385b45040] mb P  I16..4:  9.3%  0.0%  0.0%  P16..4:  0.4%  0.0%  0.0%  0.0%  0.0% skip:90.3%
  
  [libx264 @ 000001e385b45040] coded y,u,v intra: 17.9% 0.0% 0.0% inter: 0.1% 0.0% 0.0%
  
  [libx264 @ 000001e385b45040] i16 v,h,dc,p: 88%  8%  4%  0%
  
  [libx264 @ 000001e385b45040] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 28% 31% 19%  3%  2%  3%  7%  4%  3%
  
  [libx264 @ 000001e385b45040] Weighted P-Frames: Y:0.0% UV:0.0%
  
  [libx264 @ 000001e385b45040] kb/s:1401.10

• How to create a live stream in dash format from mp4 file or m3u8 list ? (ffmpeg)

  30 juin 2017, par jorge.luengo

  I have been trying different ways of running dash live streams from mp4 or m3u8 but none of them worked fined. I want to use ffmpeg because of my server conditions.
  This command has been the one that did something but it didn’t work as I expected :

  ffmpeg-3.3.2-64bit-static/ffmpeg -i reencoded24eng.mp4 -vf yadif=0 -r 30 -vcodec libx264 -keyint_min 60 -g 60 -b:v 1000k -ac 2 -strict 2 -acodec aac -ab 64k -map 0:v -map 0:a -f dash -min_seg_duration 2000  -use_template 1 -use_timeline 1 -init_seg_name init-\$RepresentationID\$.mp4 -dash 1  -media_seg_name test-\$RepresentationID\$-\$Number\$.mp4 test.mpd

  The error that the dash-if conformance tool provides is the following one :

  Start XLink resolving

  XLink resolving successful

  Start MPD validation

  MPD validation successful - DASH is valid !

  Start Schematron validation

  location="/[local-name()=’MPD’ and namespace-uri()=’urn:mpeg:dash:schema:mpd:2011’]/[local-name()=’Period’ and >namespace-uri()=’urn:mpeg:dash:schema:mpd:2011’]">
  If the MPD is dynamic the Period element shall have an id.

  location="/[local-name()=’MPD’ and namespace-uri()=’urn:mpeg:dash:schema:mpd:2011’]/[local-name()=’Period’ and >namespace-uri()=’urn:mpeg:dash:schema:mpd:2011’]/*local[1]">
  Common attributes for AdaptationSet and Representation shall either be in >one of the elements but not in both.

  Schematron validation not successful - DASH is not valid !

  BUILD SUCCESSFUL
  Total time : 5 seconds

  Could anyone help me with this ?