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• Encoder (codec png) not found for output stream #0:0 [duplicate]

  7 juin 2016, par Anubhav Dhawan

  This question already has an answer here :

  • ffmpeg & png watermark issue
    
    2 answers
    

  I’m trying to create a NodeJS app that converts a video into a GIF image.

  I’m using node-gify plugin for this purpose, which uses FFmpeg and GraphicsMagick.

  Here’s my sample code :

  var gify = require('./');
  
  var http = require('http');
  
  var fs = require('fs');
  
  
  
  var opts = {
  
    height: 300,
  
    rate: 10
  
  };
  
  
  
  console.time('convert');
  
  gify('out.mp4', 'out.gif', opts, function(err) {
  
    if (err) throw err;
  
    console.timeEnd('convert');
  
    var s = fs.statSync('out.gif');
  
    console.log('size: %smb', s.size / 1024 / 1024 | 0);
  
  });

  And here’s my console error :

  > gify@0.2.0 start /home/daffodil/repos/node-gify-master
  
  > node example.js
  
  
  
  /home/daffodil/repos/node-gify-master/example.js:24
  
    if (err) throw err;
  
             ^
  
  
  
  Error: Command failed: /bin/sh -c ffmpeg -i out.mp4 -filter:v scale=-1:300 -r 10 /tmp/IP5OXJZELd/%04d.png
  
  ffmpeg version 3.0.2 Copyright (c) 2000-2016 the FFmpeg developers
  
    built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04)
  
    configuration: --disable-yasm
  
    libavutil      55. 17.103 / 55. 17.103
  
    libavcodec     57. 24.102 / 57. 24.102
  
    libavformat    57. 25.100 / 57. 25.100
  
    libavdevice    57.  0.101 / 57.  0.101
  
    libavfilter     6. 31.100 /  6. 31.100
  
    libswscale      4.  0.100 /  4.  0.100
  
    libswresample   2.  0.101 /  2.  0.101
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'out.mp4':
  
    Metadata:
  
      major_brand     : mp42
  
      minor_version   : 1
  
      compatible_brands: mp42mp41
  
      creation_time   : 2005-02-25 02:35:57
  
    Duration: 00:01:10.00, start: 0.000000, bitrate: 106 kb/s
  
      Stream #0:0(eng): Audio: aac (LC) (mp4a / 0x6134706D), 8000 Hz, stereo, fltp, 19 kb/s (default)
  
      Metadata:
  
        creation_time   : 2005-02-25 02:35:57
  
        handler_name    : Apple Sound Media Handler
  
      Stream #0:1(eng): Video: mpeg4 (Advanced Simple Profile) (mp4v / 0x7634706D), yuv420p, 192x242 [SAR 1:1 DAR 96:121], 76 kb/s, 15 fps, 15 tbr, 600 tbn, 1k tbc (default)
  
      Metadata:
  
        creation_time   : 2005-02-25 02:35:57
  
        handler_name    : Apple Video Media Handler
  
      Stream #0:2(eng): Data: none (rtp  / 0x20707472), 4 kb/s (default)
  
      Metadata:
  
        creation_time   : 2005-02-25 02:35:57
  
        handler_name    : hint media handler
  
      Stream #0:3(eng): Data: none (rtp  / 0x20707472), 3 kb/s (default)
  
      Metadata:
  
        creation_time   : 2005-02-25 02:35:57
  
        handler_name    : hint media handler
  
  Output #0, image2, to '/tmp/IP5OXJZELd/%04d.png':
  
    Metadata:
  
      major_brand     : mp42
  
      minor_version   : 1
  
      compatible_brands: mp42mp41
  
      Stream #0:0(eng): Video: png, none, q=2-31, 128 kb/s (default)
  
      Metadata:
  
        creation_time   : 2005-02-25 02:35:57
  
        handler_name    : Apple Video Media Handler
  
  Stream mapping:
  
    Stream #0:1 -> #0:0 (mpeg4 (native) -> ? (?))
  
  Encoder (codec png) not found for output stream #0:0
  
  
  
      at ChildProcess.exithandler (child_process.js:213:12)
  
      at emitTwo (events.js:100:13)
  
      at ChildProcess.emit (events.js:185:7)
  
      at maybeClose (internal/child_process.js:827:16)
  
      at Socket.<anonymous> (internal/child_process.js:319:11)
  
      at emitOne (events.js:90:13)
  
      at Socket.emit (events.js:182:7)
  
      at Pipe._onclose (net.js:471:12)
  
  </anonymous>

  PS : I had a couple of problems installing FFmpeg on my Ubuntu 14.04.

  • First, FFmpeg is removed from Ubuntu 14.04 (legal issues AFAIK). But I managed to apt-get it through this.
  • Second, when I tried to ./configure (as mentioned in its README.md), I got this error - yasm/nasm not found or too old. Use --disable-yasm for a crippled build.. So I used ./configure --disable-yasm instead, and it (somehow) worked.

  Update #1

  After read this log a couple of times, I managed to produce a sample GIF from my mp4 file, by changing the command, which example.js tries to run :

  From

  ffmpeg -i out.mp4 -filter:v scale=-1:300 -r 10 /tmp/Lz43nx6wv1/%04d.png

  To

  ffmpeg -i out.mp4 -filter:v scale=-1:300 -r 10 out.gif

  But it’s still using command line, I need to do this by code.

  So I dived into the code and found that this wrong url is coming from the plugin’s index.js :

  ...
  
  
  
  // tmpfile(s)
  
    var id = uid(10);
  
    var dir = path.resolve('/tmp/' + id);
  
    var tmp  = path.join(dir, '/%04d.png');
  
  
  
  ...

  Is this an issue with the plugin, or am I doing something wrong here ?
  In any case, please put the correct stub here, because I don’t want to touch this part unless I know what I’m doing ?

  Update #2

  Now I installed zlib1g-dev, and then reinstalled both FFmpeg and graphicsMagick, and now I see this error :

  gm convert: No decode delegate for this image format (/tmp/ZQbEAynAcf/0702.png).

  Thanks in advance :)

• Could not open encoder using ffmpeg C APi for MOV format

  22 juin 2016, par lupod

  Context

  I am writing a program for doing some video processing on an input file. I wrote two classes for handling the "reading/writing frames" part that essentially wrap the functions of ffmpeg. These classes may be instantiated by providing an input and output file name, and in their constructor I initialize everything that is needed (or at least I hope so).

  This are the two routines that are called inside the constructors :

  // InputVideoHandler.cpp
  
  void InputVideoHandler::init(char* name) {
  
    streamIndex = -1;
  
    int numStreams;
  
  
  
    if (avformat_open_input(&formatCtx, name, NULL, NULL) != 0)
  
      throw std::exception("Invalid input file name.");
  
  
  
    if (avformat_find_stream_info(formatCtx, NULL)<0)
  
      throw std::exception("Could not find stream information.");
  
  
  
    numStreams = formatCtx->nb_streams;
  
  
  
    if (numStreams < 0)
  
      throw std::exception("No streams in input video file.");
  
  
  
    for (int i = 0; i < numStreams; i++) {
  
      if (formatCtx->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
  
        streamIndex = i;
  
        break;
  
      }
  
    }
  
  
  
    if (streamIndex < 0)
  
      throw std::exception("No video stream in input video file.");
  
  
  
    // find decoder using id
  
    codec = avcodec_find_decoder(formatCtx->streams[streamIndex]->codec->codec_id);
  
    if (codec == nullptr)
  
      throw std::exception("Could not find suitable decoder for input file.");
  
  
  
    // copy context from input stream
  
    codecCtx = avcodec_alloc_context3(codec);
  
    if (avcodec_copy_context(codecCtx, formatCtx->streams[streamIndex]->codec) != 0)
  
      throw std::exception("Could not copy codec context from input stream.");
  
  
  
    if (avcodec_open2(codecCtx, codec, NULL) < 0)
  
      throw std::exception("Could not open decoder.");
  
  
  
    codecCtx->refcounted_frames = 1;
  
  }
  
  
  
  // OutputVideoBuilder.cpp
  
  void OutputVideoBuilder::init(char* name, AVCodecContext* inputCtx) {
  
    if (avformat_alloc_output_context2(&formatCtx, NULL, NULL, name) < 0)
  
      throw std::exception("Could not determine file extension from provided name.");
  
  
  
    codec = avcodec_find_encoder(inputCtx->codec_id);
  
    if (codec == nullptr) {
  
      throw std::exception("Could not find suitable encoder.");
  
    }
  
  
  
    codecCtx = avcodec_alloc_context3(codec);
  
    if (avcodec_copy_context(codecCtx, inputCtx) < 0)
  
      throw std::exception("Could not copy output codec context from input");
  
  
  
    codecCtx->time_base = inputCtx->time_base;
  
  
  
    if (avcodec_open2(codecCtx, codec, NULL) < 0)
  
      throw std::exception("Could not open encoder.");
  
  
  
    stream = avformat_new_stream(formatCtx, codec);
  
    if (stream == nullptr) {
  
      throw std::exception("Could not allocate stream.");
  
    }
  
  
  
    stream->id = formatCtx->nb_streams - 1;
  
    stream->codec = codecCtx;
  
    stream->time_base = codecCtx->time_base;
  
  
  
    av_dump_format(formatCtx, 0, name, 1);
  
    if (!(formatCtx->oformat->flags & AVFMT_NOFILE)) {
  
      if (avio_open(&formatCtx->pb, name, AVIO_FLAG_WRITE) < 0) {
  
        throw std::exception("Could not open output file.");
  
      }
  
    }
  
  
  
    if (avformat_write_header(formatCtx, NULL) < 0) {
  
      throw std::exception("Error occurred when opening output file.");
  
    }
  
  
  
  }

  As you see, for the Init function of the output handler I require that an AVCodecContext must be provided. In my code, I pass to the constructor the AVCodecContext that is stored in the input handler and that was previously created.

  Question :

  The two functions work fine when I test my program with some video formats, like .mpg or .avi. When I try to process .mov/.mp4 files, however, my code throws the exception that I labeled "Could not open encoder." in OutputVideoBuilder::Init(). Why is this happening ? I read from the General documentation of ffmpeg that that format should be supported as well by ffmpeg. I am assuming that I am doing something wrong in my code, which I do not completely understand because it was created by trying to adapt the tutorials of the documentation to my specific case. Also for this reason, any comments on things that are useless or things that are missing will be greatly appreciated.

• compile ffmpeg decode only without audio codecs

  28 juillet 2016, par Rob

  I work on a media manager and use ffmpeg.exe to extract screenshots.
  With the latest size of ffmpeg.exe exceeding 35MB, I am attempting to build ffmpeg without the majority of its functions, to allow only saving of a frame of video.

  I had thought disabling many of the filters, Audio Codecs etc would shrink the size of ffmpeg to something more manageable.

  Following this guide
  https://pracucci.com/compile-ffmpeg-on-windows-with-visual-studio-compiler.html
  to allow building of ffmpeg using Visual Studio 2015, I have come to the part of ./configuration and hit a wall.
  With so many options and no idea what all of them mean or do, I am asking if someone in the community can give me laymans instructions.

  I also know that I need to build x264, and possible x265 (HEVC), but am not sure if there is anything other codecs needed.
  In the end, I and am hoping to just have the one file, ffmpeg.exe for use in the media manager project.

  The code I use to get a screenshot is as follows

  Public Shared Function CreateScreenShot(ByVal FullPathAndFilename As String, ByVal SavePath As String, ByVal sec As Integer, Optional ByVal Overwrite As Boolean = False) As Boolean
  
      If Not File.Exists(SavePath) Or Overwrite Then
  
          Try
  
              IO.File.Delete(SavePath)
  
          Catch
  
              Return False
  
          End Try
  
          If IO.File.Exists(FullPathAndFilename) Then
  
              Dim myProcess As Process = New Process
  
              Try
  
                  Dim seconds As Integer = sec
  
                  myProcess.StartInfo.WindowStyle = ProcessWindowStyle.Hidden
  
                  myProcess.StartInfo.CreateNoWindow = False
  
                  myProcess.StartInfo.FileName = Utilities.applicationPath & "\Assets\ffmpeg.exe"
  
                  Dim proc_arguments As String = "-ss " & seconds.ToString & " -i """ & FullPathAndFilename & """ -vframes:v 1 -an " & """" & SavePath & """"
  
                  myProcess.StartInfo.Arguments = proc_arguments
  
                  myProcess.Start()
  
                  myProcess.WaitForExit()
  
                  If File.Exists(SavePath) Then Return True
  
              Catch ex As Exception
  
                  Throw ex
  
              Finally
  
                  myProcess.Close()
  
              End Try
  
          End If
  
      End If
  
      Return False
  
  End Function

  I hope this is sufficient information, and appreciated any help or suggestions.