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• avformat/utils : Use static mutexes instead of ff_lock_avformat()

  17 mai 2024, par Andreas Rheinhardt

  avformat/utils : Use static mutexes instead of ff_lock_avformat()
  Its existence is a remnant of (libavcodec's) lock-manager API
  
  which has been removed in a04c2c707de2ce850f79870e84ac9d7ec7aa9143.
  
  There is no need to use the same lock for avisynth, chromaprint
  
  or tls, so switch to ordinary static mutexes instead.
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
  

  • [DH] libavformat/avisynth.c
  • [DH] libavformat/chromaprint.c
  • [DH] libavformat/internal.h
  • [DH] libavformat/tls_gnutls.c
  • [DH] libavformat/tls_openssl.c
  • [DH] libavformat/utils.c

• Decoding RIMM streaming file format

  10 septembre 2011, par Thomas

  I want to decode the video (visual) frames within a Blackberry RIMM file. So far I have a parser, and some corresponding container documentation from RIM. 

  The video codec is H264 and is explicitly set on the device using one of the video.encodings properties. However, FFMPEG is not able to decode the frames and this is driving me nuts.

  Edit 1 : The issues seems to be lack of SPS and PPS in the frames, and artificially inserting them have proven unsuccessful so far (all grey image). Blackberry 9700 sends

  0x00 0x00 0x ?? 0x ?? 0xType

  where Type is according to table 7-1 in the H264 spec (I and P frames). We believe the 0x ?? 0x ?? represent the size of the frame, however the size does not always correspond to the size found by the parser (the parser seems to be working correctly).

  I have a windows decoder codec from blackberry, called mc_demux_mp2_ds.ax, and can play some MPEG-4 files captured the same way, but it is a binary for windows. And the H264 files will not play either way. I am aware of previous attempts. The capture url for javax.microedition.media.Manager is

  encoding=video-3gpp_width=176_height=144_video_codec=H264_audio_codec=AAC

  and I am writing to an output stream. Some example files here.

  Edit 2 :Turns out that about 3-4 of the 12-15 available video capture modes are flat out failing and refusing to output data, even in the simplest of test applications. So any working solution should implement MPEG-4, H264 and H263 in both AMR and AAC, in so getting fallback alternatives when one sound codec and/or resolution fails. Reboots, hangs and what not litters the Blackberry video implementation and vary from firmware to firmware ; total suckage.

• FFMpeg extremely slow - when called from asp.net

  9 juillet 2013, par Daveo

  I have a C# .NET website hosted on WIN2003 IIS6. This calls a .exe I have made (also in .net) using System.Diagnostics.Process which in turn calls a .bat script to convert a video into web formats (h264/MP4 and WEBM)

  ::Make MP4 ffmpeg.exe -i "%1" -y -vcodec libx264 -pix_fmt yuv420p
  -vprofile high -b:v 600k -maxrate 600k -bufsize 1200k -s 480x320 -threads 0 -acodec libvo_aacenc -b:a 128k "%2\video.mp4"

  ::Make WemM (VP8 / Vorbis) ffmpeg.exe -i "%1" -y -vcodec libvpx -b:v
  600k -maxrate 600k -bufsize 1200k -s 480x320 -threads 3 -acodec
  libvorbis -f webm "%2\video.webm"

  When I test it it seems to work fine a 70Mb input file will take about 4 minute to convert to mp4 then 6 minutes to convert to webm. Which is fine ! However whenever the customer test it the ffmpeg encoding taking HOURS (5 - 10 hours for one video) .

  When I look at windows task manager it shows a 2-3 instances of ffmpeg using cpu. When I refresh the output folder I can see the file increasing at 1Kb / second very slow. Why could this be happening ?

  my .net code

  private  bool Convert(string inputFile, string outputFolder)
  
          {
  
              string exePath = ConfigurationManager.AppSettings["BatchFile"];
  
              ProcessStartInfo startInfo = new ProcessStartInfo(exePath);
  
  
  
              startInfo.Arguments = string.Format("{0} {1}", inputFile, outputFolder);
  
              startInfo.FileName = exePath;
  
              startInfo.UseShellExecute = true;
  
              startInfo.CreateNoWindow = true;
  
  
  
  
  
              using (Process process = new Process())
  
              {
  
                  process.StartInfo = startInfo;
  
  
  
                  try
  
                  {
  
                      bool success;
  
                      int waitTimeInMinutes = int.Parse(ConfigurationManager.AppSettings["VideoConversionTimeout"]);
  
                      process.Start();
  
                      process.WaitForExit(1000 * 60 * waitTimeInMinutes); // Give up after Xmins 
  
  
  
                      success = (process.ExitCode == 0);
  
  
  
                      return success;
  
  
  
                  }
  
                  catch (Exception e)
  
                  {
  
                      log.ErrorException("Main exception", e);
  
                      return false;
  
                  }
  
              }
  
          }