Recherche avancée

Sur d’autres sites (6437)

• How to add day suffix[st,nd,rd,th] in timestamp's date in ffmpeg command ? [duplicate]

  16 décembre 2019, par Milan Tejani

  This question already has an answer here :

  • How do you format the day of the month to say “11th”, “21st” or “23rd” (ordinal indicator) ?
    
    18 answers
    

  I am using this command to add time stamp in video :

  ffmpeg -y -i input.mp4 -vf "drawtext=fontfile=roboto.ttf:fontsize=36:fontcolor=yellow:text='%{pts\:gmtime\:1575526882\:%d %b, %Y %I\\\:%M %p}'" -preset ultrafast -f mp4 output.mp4

  this command generate date & time : 05 Dec, 2019 06:21 AM

  but i want to add day suffix after day in date like this : 05th Dec, 2019 06:21 AM

  //like 1st,2nd,3rd,4th,5th.... etc

  what changes i have to do to achieve this ?

• How to find the Quantified transformed coefficients in encoder x264 and in decoder libavcodec ?

  8 juillet 2019, par Quentin CHARRIER

  I’m a student in computer science and I am working on h264 encoder and decoder.

  I decided to use x264 and libavcodec and I downloaded code of these open libraries. Then, I searched for a month on how to do it. I think the quantified transformed coefficients are in h->dct.luma8x8 and h->dct.luma4x4 but they are no luma16x16 so I’m disappointed.

  Now, I suppose that Intra 16x16 macroblock have their coefficients in luma4x4 or luma8x8 but I’m not sure. Is there someone who knows about it and could give answers ?

  Furthermore, I have to find the same coefficients in decoder and I thought that they are in sl->mb but the coefficients in sl->mb are strange (there are a lot of 0s and values > 100 contrary to the encoder where values are close to 1-10..) I’m lost so I hope that someone have some advice to help me to continue my project.

  EDIT :

  I think the coefficients when the macroblock is encoded in 16x16IntraPrediction are in luma4x4. I always need help to understand how the decoder works.

  EDIT :

  I think the coefficients which are in sl->mb are always dequantized, maybe there is a variable who have the correct coefficient in decode_cabac_residual_internal but I didn’t find it..

• FFmpeg create output directory hierarchy

  31 janvier 2019, par David

  Recently bought an ip-cam which outputs a RTSP stream. I’m using the segment option of FFmpeg to create 60 minute long recordings.

  I want FFmpeg to write the files to a directory based on Year/Month/Date, and write to a file Hour-Minute.mp4 For example :
  /raid1/homes/share/public/recordings/queue/bedroom/2017/04/23/13-05.mp4 for a recording started on 23 april 2017, 13:05.

  Unfortunately FFmpeg seems to not create the directory hierarchy. FFmpeg quits since the directory can not be found.

  Input #0, rtsp, from 'rtsp://192.168.1.240/unicast':
  
    Metadata:
  
      title           : LIVE555 Streaming Media v2014.07.04
  
      comment         : LIVE555 Streaming Media v2014.07.04
  
    Duration: N/A, start: 0.000750, bitrate: N/A
  
      Stream #0:0: Video: h264 (High), yuv420p, 1920x1080, 90k tbr, 90k tbn, 180k tbc
  
      Stream #0:1: Audio: pcm_alaw, 8000 Hz, 1 channels, s16, 64 kb/s
  
  [segment @ 0x2557300] Using AVStream.codec to pass codec parameters to muxers is deprecated, use AVStream.codecpar instead.
  
  [segment @ 0x2557300] Failed to open segment '/raid1/homes/share/public/recordings/queue/bedroom/2017/04/23/14-19.mp4'
  
  Output #0, segment, to '/raid1/homes/share/public/recordings/queue/bedroom/%Y/%m/%d/%H-%M.mp4':
  
    Metadata:
  
      title           : LIVE555 Streaming Media v2014.07.04
  
      comment         : LIVE555 Streaming Media v2014.07.04
  
      encoder         : Lavf57.41.100
  
      Stream #0:0: Video: h264, yuv420p, 1920x1080, q=2-31, 90k tbr, 90k tbn, 90k tbc
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (copy)
  
  Could not write header for output file #0 (incorrect codec parameters ?): No such file or directory

  record.sh is as follows :

  #!/bin/sh
  
  ffmpeg -stimeout 600\
  
   -rtsp_transport udp \
  
   -i rtsp://192.168.1.240/unicast \
  
   -c copy \
  
   -map 0:0 \
  
   -f segment \
  
   -segment_time 3600 \
  
   -segment_wrap 100 \
  
   -segment_format mov \
  
   -strftime 1 \
  
   -reset_timestamps 1 \
  
   "/raid1/homes/share/public/recordings/queue/bedroom/%Y/%m/%d/%H-%M.mp4"

  I’ve tried not using a directory hierachy : "/raid1/homes/share/public/recordings/queue/bedroom/%Y-%m-%d_%H-%M.mp4". This works fine.

  $ ffmpeg -version
  
  ffmpeg version N-80901-gfebc862 Copyright (c) 2000-2016 the FFmpeg developers
  
  built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04.3)
  
  configuration: --extra-libs=-ldl --prefix=/opt/ffmpeg --mandir=/usr/share/man --enable-avresample --disable-debug --enable-nonfree --enable-gpl --enable-version3 --enable-libopencore-amrnb --enable-libopencore-amrwb --disable-decoder=amrnb --disable-decoder=amrwb --enable-libpulse --enable-libfreetype --enable-gnutls --enable-libx264 --enable-libx265 --enable-libfdk-aac --enable-libvorbis --enable-libmp3lame --enable-libopus --enable-libvpx --enable-libspeex --enable-libass --enable-avisynth --enable-libsoxr --enable-libxvid --enable-libvidstab
  
  libavutil      55. 28.100 / 55. 28.100
  
  libavcodec     57. 48.101 / 57. 48.101
  
  libavformat    57. 41.100 / 57. 41.100
  
  libavdevice    57.  0.102 / 57.  0.102
  
  libavfilter     6. 47.100 /  6. 47.100
  
  libavresample   3.  0.  0 /  3.  0.  0
  
  libswscale      4.  1.100 /  4.  1.100
  
  libswresample   2.  1.100 /  2.  1.100
  
  libpostproc    54.  0.100 / 54.  0.100

  Can FFmpeg create output directories on the go ?