Sur d’autres sites (8927)

• Detect rotation angle and rotate final video using ffmpeg version 2.8

  3 février 2016, par Hemant Kumar

  I used to work on ffmpeg 2.2 until now and was detecting rotation angle of video uploaded from android / iPhone mobiles and rotate the resulting video so that it run perfectly on a correct angle.

  But since I have updated the ffmpeg to version 2.8 I am getting this rotation problem. My queries are not rotating the videos as they were earlier.

  Here’r the commands I was using :

  To check rotation angle :

  ffprobe -of json -show_streams {$input} | grep rotate

  below is my final command to convert a video to mp4

  "ffmpeg -i {$input} -strict -2 -vcodec libx264 -preset slow -vb 500k -maxrate 500k -bufsize 1000k -vf 'scale=-1:480 ".fix_video_orientation($input)."' -threads 0 -ab 64k -s {$resolution}  -movflags faststart -metadata:s:v:0 rotate=0 {$output}";

  "fix_video_orientation" function is given below. It detect the angle of rotation of the initial video and output optimal option for rotating the final video.

  function fix_video_orientation($input){
  
  
  
  $return= ", transpose=1 ";
  
  
  
  $dd= exec("ffprobe -of json -show_streams  {$input}   | grep rotate");
  
  
  
  if(!empty($dd)){
  
  
  
  $dd=explode(":",$dd);
  
  $rotate=str_replace(",","",str_replace('"',"",$dd[1]));
  
  
  
  if($rotate=="90")return $return;
  
  
  
  else if ($rotate=="180") return ", transpose=2,transpose=2 ";
  
  
  
  else if($rotate == "270") return ", transpose=2 ";
  
  }

  Currently above script is supporting "flv","avi","mp4","mkv","mpg","wmv","asf","webm","mov","3gp","3gpp" extensions, also the script is supporting the resulting .mp4 file to play on all browsers and devices.

  Now the ffprobe command is not returning rotation angle and so a portrait video if uploaded from iphone is showing as landscape on the website.

  Output console of ffprobe command :

  ffprobe version N-77455-g4707497 Copyright (c) 2007-2015 the FFmpeg developers
  
  built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04)
  
  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-libdcadec --enable-libfreetype --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-libvo-aacenc --enable-libvidstab
  
  libavutil 55. 11.100 / 55. 11.100
  
  libavcodec 57. 20.100 / 57. 20.100
  
  libavformat 57. 20.100 / 57. 20.100
  
  libavdevice 57. 0.100 / 57. 0.100
  
  libavfilter 6. 21.101 / 6. 21.101
  
  libavresample 3. 0. 0 / 3. 0. 0
  
  libswscale 4. 0.100 / 4. 0.100
  
  libswresample 2. 0.101 / 2. 0.101
  
  libpostproc 54. 0.100 / 54. 0.100
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/standard/PORTRAIT.m4v':
  
  Metadata:
  
  major_brand : qt
  
  
  
  minor_version : 0
  
  compatible_brands: qt
  
  
  
  creation_time : 2016-02-03 05:25:18
  
  com.apple.quicktime.make: Apple
  
  com.apple.quicktime.model: iPhone 4S
  
  com.apple.quicktime.software: 9.2.1
  
  com.apple.quicktime.creationdate: 2016-02-03T10:52:11+0530
  
  Duration: 00:00:03.34, start: 0.000000, bitrate: 7910 kb/s
  
  Stream #0:0(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, mono, fltp, 63 kb/s (default)
  
  Metadata:
  
  creation_time : 2016-02-03 05:25:18
  
  handler_name : Core Media Data Handler
  
  Stream #0:1(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709), 720x1280 [SAR 1:1 DAR 9:16], 7832 kb/s, 29.97 fps, 29.97 tbr, 600 tbn, 50 tbc (default)
  
  Metadata:
  
  creation_time : 2016-02-03 05:25:18
  
  handler_name : Core Media Data Handler
  
  encoder : H.264
  
  Stream #0:2(und): Data: none (mebx / 0x7862656D), 0 kb/s (default)
  
  Metadata:
  
  creation_time : 2016-02-03 05:25:18
  
  handler_name : Core Media Data Handler
  
  Stream #0:3(und): Data: none (mebx / 0x7862656D), 0 kb/s (default)
  
  Metadata:
  
  creation_time : 2016-02-03 05:25:18
  
  handler_name : Core Media Data Handler
  
  Unsupported codec with id 0 for input stream 2
  
  Unsupported codec with id 0 for input stream 3

  If latest version of ffmpeg (2.8) is used to auto rotate the video, can you please suggest me what option I need to add or remove from my final command.

• FFmpeg command to apply multiple filters and limit the final file size

  16 mars 2016, par Konrad — ffmpeg

  I’m using ffmpeg command below to convert video to a format of the defined scale and in order to hardcode the subtitles

  Original syntax

  ffmpeg -i "Original File.mov"  -vf subtitles=Subtitles.srt -vf scale=1920:1080 \
  
         -crf 12 "Final File".mov

  Problem

  I would like to expand this command further and :

  • ensure that the produce file is under 2GB
  • I would like to include additional parameters with advanced subtitle options, like setting the canvas size and fixing the potential delay

  Side notes

  I reckon that in case of predefining the file size the -crf 12 paramater will be redundant ?

• Why the bitrate shown during processing differs so much from the final bitrate after processing using ffmpeg ?

  28 juillet 2016, par rpgmaker

  Using ffmpeg, why the bitrate shown during processing differs so much from the final bitrate after processing ?

  This command on a 1080p source :

  ffmpeg -i "$name" -i "$subname" -map 0 -map 1 -vf scale=-1:720 -c:v libx264 -preset veryslow -crf 21 -c:a aac -b:a 256k -c:s:0 srt -disposition:s:0 default -metadata:s:s:0 language=eng -metadata:s:v:0 title="$title" "$new"

  Shows this output :
  

  Which essentially averages 1300-1400 kBit/s. But when I calculate the bitrate of the resulting video using mkvinfo -t the bitrate shown sits at 970-1000 kBit/s and that’s not even close to averaging the 1300 kBit/s shown throughout processing. What is causing the disparity ?