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• Video out of LinkedList sequence

  14 janvier 2020, par Marks Gniteckis

  I just started working on a side project to learn JavaFX 13 and the idea is to play a sequence of frames like a video without saving the actual video or frames in temp folders. I’d like to buffer images and output them onto ImageView at 30fps. Here is what I’ve got so far :

  The method that buffers images -

  @FXML void takeVideo(ActionEvent event)
  
              throws InterruptedException {
  
          model.purgeBufferedVideo();
  
          Timer timer = new Timer();
  
          long startedAt = System.currentTimeMillis();
  
          TimerTask task = new TimerTask() {
  
              @Override public void run() {
  
                  while (System.currentTimeMillis() < startedAt + (1000 * Long.parseLong(s.getText()))) {
  
                      generateVideo(new Rectangle(Toolkit.getDefaultToolkit()
  
                              .getScreenSize()));
  
                      System.out.println(System.currentTimeMillis() != startedAt + (1000 * Long
  
                              .parseLong(s.getText())));
  
                  }
  
                  cancel();
  
                  System.out.println("Video buffered");
  
              }
  
          };
  
          timer.schedule(task, 0L);
  
      }

  Method to output images onto ImageView -

  @FXML void playVideo(ActionEvent event) {
  
          model.getBufferedVideo().forEach(i -> {
  
  
  
              try {
  
                  preview.setImage(i);
  
                  Thread.sleep((60000 / Long.parseLong(s.getText()))/30);
  
                  preview.setImage(i);
  
              } catch (InterruptedException e) {
  
                  e.printStackTrace();
  
              }
  
          });
  
      }

  List population is working but only last image in the list is displayed in the ImageView and I can’t really get my head around why... Thanks in advance to everyone !

• How to export audio from a iPhone video file with FFmpeg ?

  11 janvier 2020, par DanScripter

  UPDATE 1 the problem resides in the input read-stream. (check below)

  I am using fluent-ffmpeg (version : 2.1.2) to get a .mp3 file out of a video file that I input as a stream .createReadStream(). I output the file as a .pipe to a remoteWriteStream.

  ffmpeg -i pipe:0 -vn -f mp3 -acodec mp3 -movflags frag_keyframe+empty_moov pipe:1

  This works fine with .mp4, .webm and .mov (codec : prores) files.

  But it somehow does not want to work with a .mov out of an iPhone 11. FFmpeg is not giving me any error when running above code. It creates the .mp3 file but the size is just 152 B and it is not playable.

  I ffprobed the iPhone .mov files it returns this :

  "{ streams: 
  
     [ { index: 0,
  
         codec_name: 'hevc',
  
         codec_long_name: 'H.265 / HEVC (High Efficiency Video Coding)',
  
         profile: 'Main',
  
         codec_type: 'video',
  
         codec_time_base: '1111/33300',
  
         codec_tag_string: 'hvc1',
  
         codec_tag: '0x31637668',
  
         width: 1920,
  
         height: 1080,
  
         coded_width: 1920,
  
         coded_height: 1088,
  
         has_b_frames: 2,
  
         sample_aspect_ratio: '0:1',
  
         display_aspect_ratio: '0:1',
  
         pix_fmt: 'yuv420p',
  
         level: 120,
  
         color_range: 'tv',
  
         color_space: 'bt709',
  
         color_transfer: 'bt709',
  
         color_primaries: 'bt709',
  
         chroma_location: 'unspecified',
  
         field_order: 'unknown',
  
         timecode: 'N/A',
  
         refs: 1,
  
         id: 'N/A',
  
         r_frame_rate: '30000/1001',
  
         avg_frame_rate: '33300/1111',
  
         time_base: '1/600',
  
         start_pts: 'N/A',
  
         start_time: 'N/A',
  
         duration_ts: 6666,
  
         duration: 11.11,
  
         bit_rate: 7611708,
  
         max_bit_rate: 'N/A',
  
         bits_per_raw_sample: 'N/A',
  
         nb_frames: 333,
  
         nb_read_frames: 'N/A',
  
         nb_read_packets: 'N/A',
  
         tags: [Object],
  
         disposition: [Object] },
  
       { index: 1,
  
         codec_name: 'aac',
  
         codec_long_name: 'AAC (Advanced Audio Coding)',
  
         profile: 'unknown',
  
         codec_type: 'audio',
  
         codec_time_base: '1/44100',
  
         codec_tag_string: 'mp4a',
  
         codec_tag: '0x6134706d',
  
         sample_fmt: 'fltp',
  
         sample_rate: 44100,
  
         channels: 2,
  
         channel_layout: 'stereo',
  
         bits_per_sample: 0,
  
         id: 'N/A',
  
         r_frame_rate: '0/0',
  
         avg_frame_rate: '0/0',
  
         time_base: '1/44100',
  
         start_pts: 'N/A',
  
         start_time: 'N/A',
  
         duration_ts: 489951,
  
         duration: 11.11,
  
         bit_rate: 135091,
  
         max_bit_rate: 192000,
  
         bits_per_raw_sample: 'N/A',
  
         nb_frames: 481,
  
         nb_read_frames: 'N/A',
  
         nb_read_packets: 'N/A',
  
         tags: [Object],
  
         disposition: [Object] },
  
       { index: 2,
  
         codec_name: 'unknown',
  
         codec_long_name: 'unknown',
  
         profile: 'unknown',
  
         codec_type: 'data',
  
         codec_tag_string: 'mebx',
  
         codec_tag: '0x7862656d',
  
         id: 'N/A',
  
         r_frame_rate: '0/0',
  
         avg_frame_rate: '0/0',
  
         time_base: '1/600',
  
         start_pts: 'N/A',
  
         start_time: 'N/A',
  
         duration_ts: 6666,
  
         duration: 11.11,
  
         bit_rate: 2670,
  
         max_bit_rate: 'N/A',
  
         bits_per_raw_sample: 'N/A',
  
         nb_frames: 38,
  
         nb_read_frames: 'N/A',
  
         nb_read_packets: 'N/A',
  
         tags: [Object],
  
         disposition: [Object] },
  
       { index: 3,
  
         codec_name: 'unknown',
  
         codec_long_name: 'unknown',
  
         profile: 'unknown',
  
         codec_type: 'data',
  
         codec_tag_string: 'mebx',
  
         codec_tag: '0x7862656d',
  
         id: 'N/A',
  
         r_frame_rate: '0/0',
  
         avg_frame_rate: '0/0',
  
         time_base: '1/600',
  
         start_pts: 'N/A',
  
         start_time: 'N/A',
  
         duration_ts: 6666,
  
         duration: 11.11,
  
         bit_rate: 7,
  
         max_bit_rate: 'N/A',
  
         bits_per_raw_sample: 'N/A',
  
         nb_frames: 1,
  
         nb_read_frames: 'N/A',
  
         nb_read_packets: 'N/A',
  
         tags: [Object],
  
         disposition: [Object] },
  
       { index: 4,
  
         codec_name: 'unknown',
  
         codec_long_name: 'unknown',
  
         profile: 'unknown',
  
         codec_type: 'data',
  
         codec_tag_string: 'mebx',
  
         codec_tag: '0x7862656d',
  
         id: 'N/A',
  
         r_frame_rate: '0/0',
  
         avg_frame_rate: '0/0',
  
         time_base: '1/600',
  
         start_pts: 'N/A',
  
         start_time: 'N/A',
  
         duration_ts: 6666,
  
         duration: 11.11,
  
         bit_rate: 18117,
  
         max_bit_rate: 'N/A',
  
         bits_per_raw_sample: 'N/A',
  
         nb_frames: 333,
  
         nb_read_frames: 'N/A',
  
         nb_read_packets: 'N/A',
  
         tags: [Object],
  
         disposition: [Object] } ],
  
    format: 
  
     { filename: 'pipe:0',
  
       nb_streams: 5,
  
       nb_programs: 0,
  
       format_name: 'mov,mp4,m4a,3gp,3g2,mj2',
  
       format_long_name: 'QuickTime / MOV',
  
       start_time: 'N/A',
  
       duration: 11.11,
  
       size: 'N/A',
  
       bit_rate: 'N/A',
  
       probe_score: 100,
  
       tags: 
  
        { major_brand: 'qt  ',
  
          minor_version: '0',
  
          compatible_brands: 'qt  ',
  
          creation_time: '2020-01-11T12:33:36.000000Z',
  
          'com.apple.quicktime.make': 'Apple',
  
          'com.apple.quicktime.model': 'iPhone 11',
  
          'com.apple.quicktime.software': '13.3',
  
          'com.apple.quicktime.creationdate': '2020-01-11T13:33:36+0100' } },
  
    chapters: [] }" 

  The created .mp3 file results in a undefined.

  I already tried to take the .mov re-encode it to an .mp4 via ffmpeg and then try the above code to get the .mp3 - still does not work.

  Any advice how I can make this work ?

  thanks !

  ---

  UPDATE 1
  The problem resides in the input stream ! When I download the file to the local machine and input it as as a local file, not as a read stream, it works perfectly.

  I am creating the stream from a google cloud bucket like this :

  const myBucket = storage.bucket('myBucket');
  
  const remoteReadStream = myBucket.file(file).createReadStream();

  Since this code is perfectly working with all other codecs, what maybe the issue while creating the read stream from the google cloud from a h265 file ?

• Video size optimization

  21 janvier 2020, par Heba Gamal Eldin

  I’m working on a task that should optimize the video’s size before uploading to the server in a web application.
  So i want my model to automatically optimize each input video size.

  I have many trials in different approaches like FFmpeg :
  I used libx265, h264 and lib265 as a codec, with some videos it increases the video size and others minimize it with little ratio and it takes so long to generate the output file.

  for example with video of size 8M

  input = {input_name: None}
  
  output = {output_name: '-n preset faster -vcodec libx265 -crf 28'} 

  The output file is 10M.

  And also tried OpenCV :
  But the output videos aren’t written the file appears 0kb size.

  ex : with input video resolution (1280×544)
  I want to down scale it by :

  cap= cv2.VideoCapture(file_name)
  
  cap.set(3,640)
  
  cap.set(4,480)
  
  codec = cv2.VideoWriter_fourcc(*'XDIV')
  
  out = cv2.VideoWriter(output_file, codec, 28.0 , (640,480))
  
  While cap.isOpened():
  
     bol, frame = cap.read()
  
     out.write(frame)
  
     cv2.imshow('video', frame)

  I become little bit confused. what are the parameters of the input,output videos i should consider to be optimized and make a vital size change in each specific video ? Is it the codec, width, height only ?

  What is the most effective approach to do this ?

  Should i build a predictive model for estimating the suitable output video file parameters or there is a method that auto adjust ?

  if there’s an illustrative example please provide me.