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• Converting DAV to MP4 and OGG

  27 mars 2015, par mackowiakp

  I want to prepare WEB page containing films from security camera recorders. Each recorder transmit video files in DAV format so each film is converted to MP4 format by script, using such syntax :

  ffmpeg -y -i movie.dav -vcodec libx264 -crf 24 movie.mp4

  So I included in HTMLv5 code such entry :

   <video width="320" height="240">
  
    <source src="movie.mp4" type="video/mp4">
  
  </source></video> 

  It works correctly with Chrome but not with Firefox. For proper work in FF it is necessary add link to OGG file. So correct HTMLv5 syntax for both browsers should look like this :

   <video width="320" height="240">
  
    <source src="movie.mp4" type="video/mp4">
  
    <source src="movie.ogg" type="video/ogg">
  
  </source></source></video>

  Can anybody help me to pass correct ffmpeg syntax to create OGG file ?

  Output from console after using -movflags +faststart options

  [maciek@piotr MMM]$ ../ffmpeg-2.4.2-64bit-static/ffmpeg -movflags +faststart -y -i   04.24.23-04.24.38\[M\]\[@0\]\[0\].dav -vcodec libx264 -crf 24 10.mp4
  
  ffmpeg version 2.4.2-   http://johnvansickle.com/ffmpeg/    Copyright (c) 2000-2014 the FFmpeg developers
  
    built on Oct  9 2014 07:24:56 with gcc 4.8 (Debian 4.8.3-11)
  
    configuration: --enable-gpl --enable-version3 --disable-shared --disable-debug --enable-runtime-cpudetect --enable-libmp3lame --enable-libx264 --enable-libx265 --enable- libwebp --enable-libspeex --enable-libvorbis --enable-libvpx --enable-libfreetype --enable-fontconfig --enable-libxvid --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-gray --enable-libopenjpeg --enable-libopus --disable-ffserver --enable-libass --enable-gnutls --cc=gcc-4.8
  
    libavutil      54.  7.100 / 54.  7.100
  
    libavcodec     56.  1.100 / 56.  1.100
  
    libavformat    56.  4.101 / 56.  4.101
  
    libavdevice    56.  0.100 / 56.  0.100
  
    libavfilter     5.  1.100 /  5.  1.100
  
    libswscale      3.  0.100 /  3.  0.100
  
    libswresample   1.  1.100 /  1.  1.100
  
    libpostproc    53.  0.100 / 53.  0.100
  
  Option movflags not found.

• ffmpeg status & quality / cuda (CPU/GPU)

  18 avril 2015, par cocco

  ffmpeg am i doing it right ?

  So much time has passed since i use ffmpeg to convert clips on my home web server, now that mp4 (h264 & aac) is the current overall standard (works on every console, smartphone, smartTV, pc) i decided to convert my old clips from various digital cameras to to this new container/codecs.

  1. less space & the same quality.
  2. compatibility
  3. support for tags (subler for mac)

  after some research i opted for ffmpeg because of various reasons

  1. commandline (i made my simple web interface with default settings wich i execute with php’s exec)
  2. the quality/size amount

  I read that many expensive video conversion softwares are not able to handle low bitrate videos properly. I also tested some of them and personally i could not find the proper export settings or i was not impressed by the results... some had fixed default export setings, most had a lower video quality at the same filesize. ffmpeg allows me to set the -crf (18-24 usually) and -preset (veryslow, fast..) witch allows me to reduce the filesize drastically mantaining the same
  visible quality.

  Said that i’m using the preset at veryslow.(there is also placebo but the final video file is only 1% smaller in size).

  And here is the command i use

  ffmpeg
  
  -y //overwrite the file if it exists
  
  
  
  -i INPUTFILE // replace with the input file
  
  
  
  -metadata title=THETITLE // set a nice title, visible on modern devices
  
  -metadata date=THEDATE // set a nice title, visible on modern devices
  
  
  
  -c:v libx264 // use the h264 codec
  
   -crf 21 // try different numbers between 18-26
  
   -preset veryslow // placebo,slow,fast,ultrafast==big file 
  
   -tune film // tune it a little
  
   -pix_fmt yuv420p // preferred on most modern devices
  
   -profile:v main // preferred on most modern devices
  
   -level 3.1 // preferred on most modern devices 
  
   -refs 4 // preferred on most modern devices
  
  
  
  -c:a libfdk_aac // use aac
  
   -metadata:s:a language=eng // set a language, visible on modern devices 
  
   -b:a 128k // audio bitrate 128k is like mp3 192k
  
   -ar 48000 // 44100 ... whatever
  
   -ac 2 // audiochannels
  
   -movflags +faststart //move the metadata in the front of the video so it loads faster
  
  
  
  OUTPUTFILE

  some camcorder clips with m2ts already have the avc/h264 compatible codec so i just copy the stream.
  some have the ac3/dolby sorround audio. I convert the audio but keep the ac3 as second audio track mapping the ffmpeg streams.this allows me to watch the mp4 on browsers and mobile devices but i’m able to keep the surround sound to playback on some tv’s, advanced media players or devices like apple tv.

  not that i’m not happy with the speed (using quad core’s) but i recently read again about cuda opencl and there is also the simple fact that i’m not using other converters than ffmpeg since alot of time.

  Is ffmpeg (with the setting i use) a good converter to keep the same video quality than the source reducing the space occupied by and average of 30-40% ?

  Is GPU conversion really that bad (cuda .. testing a gtx970) ?
  it would be nice to add some more speed to the conversions by using both the gpu and the cpu..but for my understanding they cannot work together ??? and using only gpu is a drastical quality loss...cpu si more precise, gpu is faster in calculation are too imprecise from what i read.. so expensive softwares use cuda only for preview purpose... right ?

  Is ffmpeg or another software compatible with CPU+GPU encoding ?
  i really don’t remember where, but i read that the ffmpeg is not a good videoconverter.

  i’m really happy with the size/quality, i gained an average of 30% in space with no visible quality loss. With some extra parameters i can adjust some really old analog videos that are deinterlaced in a really bad way.

  maybe i could gain more size/quality with another software ???

  note : i like ffmpeg.it’s free and it has commandline so i can create my own interface with php html & js and use it on various machines without the need to install it in every device i use. i uplad the idevice clips directly to the ffmpeg server.

  btw. : explain the downvotes...

  EDIT :

  @talonmies ...cuda tag removed :

  http://www.nvidia.com/object/cuda_home_new.html

  CUDA® is a parallel computing platform and programming model invented
  by NVIDIA. It enables dramatic increases in computing performance by
  harnessing the power of the graphics processing unit (GPU). With
  millions of CUDA-enabled GPUs sold to date, software developers,
  scientists and researchers are finding broad-ranging uses for GPU
  computing with CUDA. Here are a few examples : - See more at :
  http://www.nvidia.com/object/cuda_home_new.html#sthash.dEYaqae7.dpuf

  isn’t cuda the programming model that a theoretical ffmpeg library should support to handle GPU encoding on nvidia cards like the gtx 970 ?? like the badaboom software http://www.geforce.com/games-applications/pc-applications/badaboom-media-converter.

• Real Time Audio and Video Streaming in C#

  16 novembre 2014, par Nuwan

  I am developing an application which can be used to stream audio and video in real time.
  I can stream in two different ways. I used a capture card to capture live HD stream and
  re send it. And also I need to stream local video file in real time.

  Now I capture video using OpenCV and store frames as bitmaps in blokingCollection bitmap queue.
  After that I encode video frames using ffmpeg (used c# library Nreco) and stored in a queue. Then I send that encoded data through UDP (did not used RTP/RTSP) to omxplayer in raspberry pi and it works very fine.

  Then I captured audio data using ffmpeg
  I used this command to capture and encode audio data.

                   data = ms.ToArray();
  
                   ffMpegTask = ffmpegConverter.ConvertLiveMedia(
  
                          fileName,
  
                          null,
  
                          ms,
  
                          Format.avi,
  
                          new ConvertSettings()
  
                          {                                
  
                              CustomOutputArgs = " -tune zerolatency -ss " + second + " -t " + endTime + " -strict experimental -acodec aac -ab 160k -ac 2 -ar 44100 -vn ",                             
  
                          });
  
                  ffMpegTask.Start();
  
                  ffMpegTask.Stop();
  
                  byte[] data = ms.ToArray();

  After that I saved every audio data packet to queue.

  And I tried to stream these separate audio and video data to omxplayer by using two different
  ports. and received streams by using two omxplayers. And it works fine.

  But what I need to do is multiplex this audio and video stream and send as one stream.
  what I do is first stream two streams as UDP://224.1.1.1:1250(video) and UDP://224.1.1.1:1260(audio)
  then I used nreco invoke method. We can use it to execute ffmpeg commands.

  " -re -i udp://224.1.1.1:1250 -i udp://224.1.1.1:1260 -c copy -f avi udp://224.1.1.1:1270"

  and this works for both audio and video stream but completely out of sync.

  Next thing what I do is creating another ffmpeg ConvertLiveMedia task and write audio and video data
  to that task using write method. And I stream that mux data and received using ffplay. And it plays the stream
  and the sync problem is solved. But sometimes audio and video frames are dropping and then it begins to
  play out of sync.

                  combine = new MemoryStream();
  
                  ffMpegTaskcom = ffmpegConvertercom.ConvertLiveMedia(
  
                          Format.mpeg,
  
                          combine,
  
                          Format.avi,
  
                          new ConvertSettings()
  
                          {
  
                              CustomInputArgs = " ", // windows bitmap pixel format
  
                              CustomOutputArgs = " -threads 7 -c:v libx264 -preset ultrafast -tune zerolatency -strict experimental -profile:v baseline -movflags +faststart -tune film -level 3.0 -tune zerolatency -tune film -pix_fmt yuv420p -g 250 -crf 22 -b:v 4000k -minrate 3000k -maxrate 5000k -acodec aac -ab 160k -ac 2 -ar 44100",
  
  
  
                          });
  
                  ffMpegTaskcom.Start();
  
                  byte[] streamBytesvi = null;
  
                  byte[] streamBytesau = null;
  
                  encodeQueqe.TryDequeue(out streamBytesvi);
  
                  encodeQueqeau.TryDequeue(out streamBytesau);
  
                  ffMpegTaskcom.Write(streamBytesvi, 0, streamBytesvi.Length);
  
                  ffMpegTaskcom.Write(streamBytesau, 0, streamBytesau.Length);
  
  
  
                  //ffMpegTaskcom.Wait();
  
                  ffMpegTaskcom.Stop();

  Now I need to know a good method to deliver audio and video data with synchronization.
  Please tell me what is the wrong I have done or suggest a better way to do this.

  Thank You !