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• Encode video for ipod classic

  13 janvier 2023, par mulllhausen

  I just finished installing ffmpeg on debian wheezy using these instructions - http://trac.ffmpeg.org/wiki/UbuntuCompilationGuide. Now I want to encode a video to play on my iPod classic. The video has the following info :

  



  $ mediainfo in.mp4 
General
Complete name                            : in.mp4
Format                                   : MPEG-4
Format profile                           : Base Media / Version 2
Codec ID                                 : mp42
File size                                : 1.21 GiB
Duration                                 : 55mn 10s
Overall bit rate mode                    : Variable
Overall bit rate                         : 3 130 Kbps
Encoded date                             : UTC 2010-08-25 23:38:59
Tagged date                              : UTC 2010-08-25 23:38:59

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L3.2
Format settings, CABAC                   : Yes
Format settings, ReFrames                : 2 frames
Codec ID                                 : avc1
Codec ID/Info                            : Advanced Video Coding
Duration                                 : 55mn 10s
Bit rate mode                            : Variable
Bit rate                                 : 3 000 Kbps
Maximum bit rate                         : 5 000 Kbps
Width                                    : 1 280 pixels
Height                                   : 720 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 29.970 fps
Standard                                 : NTSC
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.109
Stream size                              : 1.16 GiB (96%)
Language                                 : English
Encoded date                             : UTC 2010-07-21 13:28:49
Tagged date                              : UTC 2010-07-21 13:28:49
Color primaries                          : BT.709-5, BT.1361, IEC 61966-2-4, SMPTE RP177
Transfer characteristics                 : BT.709-5, BT.1361
Matrix coefficients                      : BT.709-5, BT.1361, IEC 61966-2-4 709, SMPTE RP177

Audio
ID                                       : 2
Format                                   : AAC
Format/Info                              : Advanced Audio Codec
Format profile                           : LC
Codec ID                                 : 40
Duration                                 : 55mn 10s
Bit rate mode                            : Variable
Bit rate                                 : 125 Kbps
Maximum bit rate                         : 270 Kbps
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 44.1 KHz
Compression mode                         : Lossy
Stream size                              : 49.4 MiB (4%)
Language                                 : English
Encoded date                             : UTC 2010-07-21 13:28:49
Tagged date                              : UTC 2010-07-21 13:28:49
mdhd_Duration                            : 3310353


  



  I have already tried just copying the video to the IPod with banshee but the video just shows a black screen. Which is the best format to play the video on the Ipod ? What ffmpeg parameters should I use ? I would like to maximize resolution while minimizing file size.

  


• How does the ProcessBuilder constructor parameter work ?

  19 septembre 2014, par Houseman

  I’m doing this :

  String[] command = {ffmpegLoc+"ffmpeg.exe",
  
              "-i ",
  
              "\""+dir+params.getString(4)+".flv"+"\"",
  
              "-copyts",
  
              "-crf 18",
  
              "-profile:v baseline",
  
              "-level 3.0",
  
              "-pix_fmt yuv420p",
  
              "-preset veryslow",
  
              "\""+dir+params.getString(4)+".mp4"+"\""};
  
      try {
  
          getLogger().info("ffmpeg command " + command);
  
          ProcessBuilder builder = new ProcessBuilder(command);
  
          builder.redirectErrorStream(true);
  
          getLogger().info("Starting process");
  
          Process process = builder.start();
  
          InputStream stream =  process.getInputStream();
  
          BufferedReader in = new BufferedReader(new InputStreamReader(process.getInputStream()));
  
          String line = null;
  
          while((line = in.readLine()) != null) {
  
            System.out.println(line);
  
          }
  
          process.waitFor();

  And I get this error from ffmpeg, which initializes correctly :

  Unrecognized option 'i '.
  
  Error splitting the argument list: Option not found

  So I thought "Maybe I don’t need to split out each argument into an array"

  So I replaced the command with this :

  String[] command = {ffmpegLoc+"ffmpeg.exe",
  
                  "-i " + "\""+dir+params.getString(4)+".flv"+"\"" + " -copyts -crf 18 -profile:v baseline -level 3.0 -pix_fmt yuv420p -preset veryslow "+"\""+dir+params.getString(4)+".mp4"+"\""};

  And now I get this :

  Unrecognized option 'i C:/Program'.
  
  Error splitting the argument list: Option not found

  What happened to that hyphen before i ?

  What happened to those double quotes wrapping the path to the .flv file ?

  What is going on here ?

  Edit :

  I dropped the escaped double-quotes, as per this answer, and now I get this :

  Unrecognized option 'i C:/Program Files (x86)/Wowza Media Systems/Wowza Streaming Engine 4.1.0/content/recorder/vid_test001.flv -copyts -crf 18 -profile:v baseline -level 3.0 -pix_fmt yuv420p -preset veryslow C:/Program Files (x86)/Wowza Media Systems/Wowza Streaming Engine 4.1.0/content/recorder/vid_test001.mp4'.
  
  Error splitting the argument list: Option not found

  And again that hyphen in front of the i is missing.

  Edit 2 :

  Let’s combine them : No escaped double-quotes combined with arguments each on their own index :

  String[] command = {ffmpegLoc+"ffmpeg.exe",
  
              "-i",
  
              dir+params.getString(4)+".flv",
  
              "-copyts", 
  
              "-crf 18",
  
              "-profile:v baseline",
  
              "-level 3.0",
  
              "-pix_fmt yuv420p",
  
              "-preset veryslow",
  
              dir+params.getString(4)+".mp4"};

  ffmpeg now gives me :

  Unrecognized option 'crf 18'.

  So we got to where we encountered our first whitespace, then failed.

• ffmpeg hevc h265 4k 10 bit

  14 juillet 2017, par Ali Jose

  I want to be able to encode 4k videos in TS files having video codec as HEVC at constant bitrate 20 Mbps, dolby audio (2 channel front L & R). This is the spec sheet as provided from my client http://159.8.5.10:3001/download/4k-specs.xlsx Im using this code :

  I used this code at first to produce a sample which conforms to their spec sheet, however the playback was not smooth neither on my side nor on their side :

  ffmpeg -i input.mov -pix_fmt yuv420p10le -c:v libx265  -b:v 19.5M -minrate 19.5M -maxrate 19.5M -muxrate 20M -x265-params "level=6.2" -r 50 -s 3840x2160 -c:a ac3 -b:a 384k -minrate 384k -maxrate 384k -channel_layout 3  output.ts

  the produced sample is found in the following link : http://159.8.5.10:3001/download/two_mns_sample.rar

  The client sent me this sample, he told me it is provided by another supplier and it is approved by their end (it matches their spec sheet and plays smoothly in their broadcast software), the sample is found under the following link : http://159.8.5.10:3001/download/approved-4k.rar

  Then the client sent me another sample, they also said that it is approved by their side (matched their specs and plays smoothly in their broadcast software) found under the following link : http://159.8.5.10:3001/download/approved-4k-2.rar

  When examining well the second approved sample, I noticed that it doesnt meet the spec sheet 100% but the differences are minor (level @ 5.1 instead of 6.2 and dolby 5.1 instead of dolby Stereo... so minor differences) but as they described, it played back smoothly in their broadcast playback. So we can understand from that that they are a bit flexible.

  My 4k source file is an mov Prores 4444, 23.97 fps, 10 bit depth, 444 chroma subsampling, variable bitrate (around 950 Mbps). To find out more info about the input file, please go to this link (MediaInfo txt export) : http://159.8.5.10:3001/download/4k-original.txt

  This is a 2mns sample trimmed clip from my original file (couldnt upload the whole source file since its 800 GB !) : http://159.8.5.10:3001/download/original-2-mns.mov

  I need an ffmpeg code that can generate a sample that complies to their specification sheet and can be played SMOOTHLY in their technical department, it was mentioned they are using 4k playbox technology (maybe airbox but it was not clear, but what we can assure is that they use good instrument for broadcast, they dont go for below average instrument/software), I need to send them samples that they later check and play on their playback system and get approved.