Newest 'ffmpeg' Questions - Stack Overflow

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• Process is being paused until I close the program

  27 mai 2017, par user924

  I made a simple program and UI for it. It has one button for starting ffmpeg.exe to decode a video:

      button.addActionListener(new ActionListener() {
          @Override
          public void actionPerformed(ActionEvent e) {
              ProcessBuilder pb = new ProcessBuilder("D:\\ffmpeg.exe", "-i", "\"D:\\video\\input.mp4\"", "\"output.mp4\"");
              try {
                  Process p = pb.start();
              } catch (IOException error) {
                  //
              }
          }
      }
  

  The problem is that after clicking the button ffmpeg starts but it doesn't do anything (in task manager it doesn't use cpu - 0%) until I close the program (UI) and then ffmpeg process starts to decode a video (only after closing the program ffmpeg starts using cpu - e.g. 24%)

  It's not duplicate: older questions proposed by Andy Thomas doesn't have an answer (solution) for my problem

• WriteToUDP only works on local machine

  26 mai 2017, par Anderson Scouto da Silva

  This script captures a flow entry by ffmpeg and writes to a UDP address.

  The error is that it does not go to the internet, it only stays on the local machine.

  It is not a problem in my internet network, because I made a stream through VLC and opened in another PC and it works normally, with the same parameters, but in this my script is only in the local PC.

  Follow the pictures to help with the question:

  http://imgh.us/1_4575.jpg

  http://imgh.us/2_3278.jpg

  http://imgh.us/3_2694.jpg

  package main
  
  import (
      "os/exec"
      "io"
      "net"
      "log"
      "fmt"
  )
  
  func main() {
      // UDP connections
      conn, err := net.ListenUDP("udp", &net.UDPAddr{IP: net.IPv4zero, Port: 0})
      if err != nil {
          log.Fatal(err)
      }
  
      // Set the write buffer on UDP
      err = conn.SetWriteBuffer(40 * 1024)
      if err != nil {
          log.Fatal(err)
      }
  
      inputSource := "C:/Users/Administrador/GoglandProjects/CASEncoder/in/teste-4k.mp4"
  
      // Starts ffmpeg capturing input
      cmdName := "ffmpeg"
      argsPipe1 := []string{
          "-hide_banner",
          "-loglevel", "panic",
          "-re",
          "-i",
          inputSource,
          "-preset",
          "superfast",
          "-c:v",
          "h264",
          "-crf",
          "0",
          "-c",
          "copy",
          "-f", "mpegts", "pipe:1",
      }
      cmdPipe1 := exec.Command(cmdName, argsPipe1...)
  
      stdoutPipe1, err := cmdPipe1.StdoutPipe()
      if err != nil {
          log.Fatal(err)
      }
      err = cmdPipe1.Start()
      if err != nil {
          log.Fatal(err)
      }
  
      chunk := make([]byte, 40 * 1024)
      for {
          // reads the output pipe from ffmpeg
          nr, err5 := stdoutPipe1.Read(chunk)
          fmt.Printf("Readed %d bytes\n", nr)
  
          if nr > 0 {
              validData := chunk[:nr]
  
              // write to UDP
              nw, err := conn.WriteToUDP(validData, &net.UDPAddr{IP: net.IP{233, 10, 10, 13}, Port: 1234})
              fmt.Printf("Writed %d bytes\n", nw)
              if err != nil {
                  log.Fatal(err)
              }
          }
  
          if err5 != nil {
              // end of file
              if err5 == io.EOF {
                  break
              }
              continue
          }
      }
  }
  

• FFmpeg conversion to Photo-JPEG is blocky [duplicate]

  26 mai 2017, par Richard210363

  This question already has an answer here:

  • ffmpeg generate higher quality images for MJPEG encoding 1 answer

  I am converting .mp4 files to .mov with the Photo-JPEG codec to use in After Effects to reduce render times.

  I have looked up the FFmpeg commands to do this and come up with:

  ffmpeg -i tower-bridge.mp4 -an -pix_fmt yuvj420p -vcodec mjpeg -f mov -y tower-bridge.mov 
  

  This works but when I look at the output video it is quite blocky; like a mosaic.

  During the conversion I get this message:

  [swscaler @ 0000000008c97fe0] deprecated pixel format used, make sure you did set range correctly
  

  Research on-line suggests I can ignore this message.

  What can I do to improve the output quality?
  
  
  MediaInfo report on Input file:

  Complete name : F:\london-tower-bridge.mp4
  Format : MPEG-4
  Format profile : Base Media
  Codec ID : isom (isom/avc1/mp42)
  File size : 18.7 MiB
  Duration : 13 s 625 ms
  Overall bit rate : 11.5 Mb/s
  

  ID : 1
  Format: AVC
  Format/Info : Advanced Video Codec
  Format profile : Baseline@L4
  Format settings, CABAC : No
  Format settings, ReFrames : 3 frames
  Codec ID : avc1
  Codec ID/Info : Advanced Video Coding
  Duration : 13 s 625 ms
  Bit rate : 11.5 Mb/s
  Maximum bit rate : 26.8 Mb/s
  Width : 1 920 pixels
  Height : 1 080 pixels
  Display aspect ratio : 16:9
  Frame rate mode : Constant
  Frame rate : 24.000 FPS
  Color space : YUV
  Chroma subsampling : 4:2:0
  Bit depth : 8 bits
  Scan type : Progressive
  Bits/(Pixel*Frame) : 0.231
  Stream size : 18.7 MiB (100%)
  Writing library : Zencoder Video Encoding System
  

  MediaInfo report on Output file:

  Complete name : F:\london-tower-bridge.mov
  Format : MPEG-4
  Format profile : QuickTime
  Codec ID : qt 0000.02 (qt )
  File size : 16.1 MiB
  Duration : 13 s 625 ms
  Overall bit rate mode : Variable
  Overall bit rate : 9 912 kb/s
  Writing application : Lavf57.72.101
  

  ID : 1 Format : JPEG
  Codec ID : jpeg
  Duration : 13 s 625 ms
  Bit rate mode : Variable
  Bit rate : 9 910 kb/s
  Width : 1 920 pixels
  Height : 1 080 pixels
  Display aspect ratio : 16:9
  Frame rate mode : Constant
  Frame rate : 24.000 FPS
  Color space : YUV
  Chroma subsampling : 4:2:0
  Bit depth : 8 bits
  Scan type : Progressive
  Compression mode : Lossy
  Bits/(Pixel*Frame) : 0.199
  Stream size : 16.1 MiB (100%)
  Language : English
  

• ffmpeg av_read_frame "Invalid data found"

  26 mai 2017, par DweebsUnited

  I am using ffmpeg to cut part of a file, following the remux example provided. However, I am having issues reading from files. I am given a file descriptor as input and an output filename, and can successfully set up the output file, read the stream info, copy all the streams, etc, etc. On the first call to av_read_frame though, I get an "Invalid data found when processing input" error. I have tried this with many different video files, and have not been able to get a single one to process correctly.

  Here is my code. I get no errors anywhere, except av_read_frame, which gives Invalid data found no matter what video file I give it.

  char path[512];
  sprintf(path, "pipe:%d", fileno(fp));
  
  
  AVOutputFormat *ofmt = NULL;
  AVFormatContext *ifmt_ctx = avformat_alloc_context(), *ofmt_ctx = NULL;
  AVPacket pkt;
  int ret, i;
  
  av_register_all();
  avcodec_register_all();
  
  if ((ret = avformat_open_input(&ifmt_ctx, path, av_find_input_format("mp4"), NULL)) < 0) {
      LOG("Could not open input file '%s'", path);
      goto end;
  }
  
  if ((ret = avformat_find_stream_info(ifmt_ctx, 0)) < 0) {
      LOG("Failed to retrieve input stream information", "");
      goto end;
  }
  
  avformat_alloc_output_context2(&ofmt_ctx, NULL, NULL, out_filename);
  if (!ofmt_ctx) {
      LOG("Could not create output context\n");
      ret = AVERROR_UNKNOWN;
      goto end;
  }
  
  ofmt = ofmt_ctx->oformat;
  
  for (i = 0; i < ifmt_ctx->nb_streams; i++) {
      AVStream *in_stream = ifmt_ctx->streams[i];
      AVStream *out_stream = avformat_new_stream(ofmt_ctx, in_stream->codec->codec);
  
      if (!out_stream) {
          LOG("Failed allocating output stream\n");
          goto end;
      }
  
      ret = avcodec_parameters_copy(out_stream->codecpar, in_stream->codecpar);
      if (ret < 0) {
          LOG("Failed to copy context from input to output stream codec context\n");
          goto end;
      }
      out_stream->codecpar->codec_tag = 0;
  }
  
  if (!(ofmt->flags & AVFMT_NOFILE)) {
      ret = avio_open(&ofmt_ctx->pb, out_filename, AVIO_FLAG_WRITE);
      if (ret < 0) {
          LOG("Could not open output file '%s'", out_filename);
          goto end;
      }
  }
  
  ret = avformat_write_header(ofmt_ctx, NULL);
  if (ret < 0) {
      LOG("Error occurred when opening output file\n");
      goto end;
  }
  
  //    int indexs[8] = {0};
  
  //    int64_t start_from = 8*AV_TIME_BASE;
  ret = av_seek_frame(ifmt_ctx, -1, from_seconds*AV_TIME_BASE, AVSEEK_FLAG_ANY);
  if (ret < 0) {
      LOG("Error seek\n");
      goto end;
  }
  
  int64_t *dts_start_from;
  int64_t *pts_start_from;
  dts_start_from = (int64_t *) malloc(sizeof(int64_t) * ifmt_ctx->nb_streams);
  memset(dts_start_from, 0, sizeof(int64_t) * ifmt_ctx->nb_streams);
  pts_start_from = (int64_t *) malloc(sizeof(int64_t) * ifmt_ctx->nb_streams);
  memset(pts_start_from, 0, sizeof(int64_t) * ifmt_ctx->nb_streams);
  
  while (1) {
      AVStream *in_stream, *out_stream;
  
      ret = av_read_frame(ifmt_ctx, &pkt);
      if (ret < 0)
          break;
  
      in_stream = ifmt_ctx->streams[pkt.stream_index];
      out_stream = ofmt_ctx->streams[pkt.stream_index];
  
      if (av_q2d(in_stream->time_base) * pkt.pts > end_seconds) {
          av_packet_unref(&pkt);
          break;
      }
  
      if (dts_start_from[pkt.stream_index] == 0)
          dts_start_from[pkt.stream_index] = pkt.dts;
      if (pts_start_from[pkt.stream_index] == 0)
          pts_start_from[pkt.stream_index] = pkt.pts;
  
      /* copy packet */
      pkt.pts = ::av_rescale_q_rnd(pkt.pts - pts_start_from[pkt.stream_index], in_stream->time_base, out_stream->time_base, (AVRounding) (AV_ROUND_NEAR_INF |
                                                                                                                                          AV_ROUND_PASS_MINMAX));
      pkt.dts = ::av_rescale_q_rnd(pkt.dts - dts_start_from[pkt.stream_index], in_stream->time_base, out_stream->time_base, (AVRounding) (AV_ROUND_NEAR_INF |
                                                                                                                                          AV_ROUND_PASS_MINMAX));
      if (pkt.pts < 0) {
          pkt.pts = 0;
      }
      if (pkt.dts < 0) {
          pkt.dts = 0;
      }
      pkt.duration = (int) av_rescale_q((int64_t) pkt.duration, in_stream->time_base, out_stream->time_base);
      pkt.pos = -1;
  
      ret = av_interleaved_write_frame(ofmt_ctx, &pkt);
      if (ret < 0) {
          LOG("Error muxing packet\n");
          break;
      }
      av_packet_unref(&pkt);
  }
  free(dts_start_from);
  free(pts_start_from);
  
  av_write_trailer(ofmt_ctx);
  
  end:
  LOG("END");
  
  avformat_close_input(&ifmt_ctx);
  
  /* close output */
  if (ofmt_ctx && !(ofmt->flags & AVFMT_NOFILE))
      avio_closep(&ofmt_ctx->pb);
  avformat_free_context(ofmt_ctx);
  
  if (ret < 0 && ret != AVERROR_EOF) {
      LOG("-- Error occurred: %s\n", av_err2str(ret));
      return 1;
  }
  

  Thank you for any help, I'm still getting used to ffmpeg. Did I miss some setting on the input? Am I not setting something up that I need to be? This problem is really stumping me.

• ffmpeg, opencv broken pipe

  26 mai 2017, par dopplesoldner

  I am trying to output opencv (version 2.4) frames to ffmpeg via pipes and am getting IOError: [Errno 32] Broken pipe error.

  import sys
  import cv2
  import numpy as np
  import subprocess
  
  cap = cv2.VideoCapture(0)
  fc = 0
  
  command = [ 'ffmpeg',
      '-y',
      '-f', 'rawvideo',
      '-vcodec','rawvideo',
      '-s', '420x360',
      '-pix_fmt', 'rgb24',
      '-r', '24', 
      '-i', '-', # The imput comes from a pipe
      '-an', # no audio
      '-vcodec', 'mpeg',
      'output.mp4' ]
  
  pipe = subprocess.Popen( command, stdin=subprocess.PIPE, stderr=subprocess.PIPE)
  
  while(cap.isOpened() and fc < 10):
      _, frame = cap.read()
      frame = cv2.resize(frame, (420, 360))
      _, buf = cv2.imencode('.jpg', frame)
      jpg = buf.tostring()
      pipe.stdin.write(jpg)
      fc += 1
  cap.release()
  

  Has anyone come across this before?