Recherche avancée

Sur d’autres sites (7070)

• Bug in ffmpeg resampling_audio.c

  31 juillet 2013, par sumodds

  I am trying to compile and run the resampling_audio.c in ffmpeg 1.2. It seems like there is a bug and the code segfaults. I debugged the code and it seems like it is crashing on

  /* convert to destination format */
  
  ret = swr_convert(swr_ctx, dst_data, dst_nb_samples, (const uint8_t **)src_data, src_nb_samples);
  
  if (ret < 0) {
  
      fprintf(stderr, "Error while converting\n");
  
      goto end;
  
  }
  
  dst_bufsize = av_samples_get_buffer_size(&dst_linesize, dst_nb_channels,
  
                                               ret, dst_sample_fmt, 1);

  The stack trace is

  #0  malloc_consolidate (av=0xb7f6f440) at malloc.c:4251
  
  #1  malloc_consolidate (av=0xb7f6f440) at malloc.c:4203
  
  #2  0xb7e4122f in _int_malloc (av=0xb7f6f440, bytes=8248) at malloc.c:3543
  
  #3  0xb7e42418 in _int_memalign (av=0xb7f6f440, alignment=32, bytes=8192) at malloc.c:4503
  
  #4  0xb7e446a0 in __GI___libc_memalign (alignment=32, bytes=8192) at malloc.c:3104
  
  #5  0xb7e45714 in __posix_memalign (memptr=memptr@entry=0xbfffed7c, alignment=alignment@entry=32, size=size@entry=8192) at malloc.c:5049
  
  #6  0x0805c0d8 in av_malloc (size=8192) at libavutil/mem.c:93
  
  #7  av_mallocz (size=size@entry=8192) at libavutil/mem.c:207
  
  #8  0x0804c35a in swri_realloc_audio (a=a@entry=0x807b860, count=2048, count@entry=1024) at libswresample/swresample.c:462
  
  #9  0x0804cc65 in swr_convert_internal (s=s@entry=0x807a180, out=out@entry=0x807ba28, out_count=out_count@entry=941, in=in@entry=0x807b7c8, in_count=in_count@entry=1024) at libswresample/swresample.c:624
  
  #10 0x0804da18 in memset (__len=<optimized out="out">, __dest=<optimized out="out">, __ch=<optimized out="out">) at /usr/include/i386-linux-gnu/bits/string3.h:85
  
  #11 fill_audiodata (out=<optimized out="out">, in_arg=<optimized out="out">) at libswresample/swresample.c:492
  
  #12 fill_audiodata (in_arg=0x8093360, out=0x807ba28) at libswresample/swresample.c:735
  
  #13 swr_convert (s=0x807a180, out_arg=0x8093360, out_count=941, in_arg=0x8092300, in_count=1024) at libswresample/swresample.c:773
  
  #14 0x0804bd5d in main (argc=2, argv=0xbffff2e4) at resampling_audio.c:194
  
  </optimized></optimized></optimized></optimized></optimized>

• How to show Images from a video as preview for playlist

  1er février 2017, par Guruprasad Rao

  You guys Have seen Youtube right. There while you are watching a video, You will also get related videos preview alongwith link. So how we can get it from video itself.. Is it possible to do so.. I am able to get the url from database and display it.. and when the link is clicked it will be played in a jquery player.. So before that a preview of that or you can say playlist of that will be available for user.

  I have updated my code with a link I found.. But still I am not able to get the Image from Video.. Is there anything wrong in my code.. Please correct me if I am wrong..

  Below is my front end code :

  <form runat="server">
  
      <div runat="server" style="height:100%;width:100%">
  
          <div>Latest Videos</div>
  
  
  
      </div>
  
  
  
      </form>

  and I am adding all my video links from backend on page load as shown below :

     try
  
      {
  
          con.Open();
  
          com = new SqlCommand("Select videourl, videoname from video order by [vid] desc",con);
  
          DbDataReader dr = com.ExecuteReader();
  
          DataTable dt = new DataTable();
  
  
  
          if (dr.HasRows)
  
          {
  
  
  
              int i = 0;
  
              dt.Load(dr);
  
              int rows = dt.Rows.Count;
  
  
  
  
  
              for (i = 0; i < rows; i++)
  
              {
  
                  HtmlGenericControl d = new HtmlGenericControl("div");
  
                  HtmlGenericControl s = new HtmlGenericControl("span");
  
                  string[] link = new string[rows];
  
                  string[] name = new string[rows];                    
  
  
  
                  d.Attributes.Add("class", "plst");
  
                  s.Attributes.Add("class", "text");
  
                  link[i] = dt.Rows[i]["videourl"].ToString();
  
                  name[i] = dt.Rows[i]["videoname"].ToString();
  
                  string videothumb = link[i];
  
                  string svthto="**Path to save Image**";
  
                  string imgpath=GetVideoThumbnail(videothumb, svthto, 30);
  
  
  
                  sb.Append("<a i="i" href=" + " class=" + ">" + name[i] + "</a>");
  
                  s.InnerHtml = sb.ToString();
  
                  d.Controls.Add(s);
  
                  examples.Controls.Add(d);
  
                  sb.Clear();
  
  
  
  
  
              }
  
          }
  
  
  
  
  
      }
  
      catch(Exception ex)
  
      {
  
          ex.Message.ToString();
  
      }
  
  
  
  public string GetVideoThumbnail(string path, string saveThumbnailTo, int seconds)
  
  {
  
      string parameters = string.Format("-ss {0} -i {1} -f image2 -vframes 1 -y {2}", seconds, path, saveThumbnailTo);
  
      string pathToConvertor = "C:\\Program Files\\ffmpeg\\ffmpeg.exe";
  
      var processInfo = new ProcessStartInfo();
  
      processInfo.FileName = pathToConvertor;
  
      processInfo.Arguments = parameters;
  
      processInfo.CreateNoWindow = true;
  
      processInfo.UseShellExecute = false;
  
  
  
      File.Delete(saveThumbnailTo);
  
  
  
      using (var process = new Process())
  
      {
  
          process.StartInfo = processInfo;
  
          process.Start();
  
          process.WaitForExit();
  
      }
  
  
  
      if (File.Exists(saveThumbnailTo))
  
          return saveThumbnailTo;
  
      else
  
          return "File not Found";
  
  }

  and here is the image of what I am getting until now :
  

  Please note : I am not concentrating on you tube videos. I am questioning regarding the videos which I store in server side folder. So if there is any jquery technique or any sort of technique to do this then please let me know. :)

• ffmpeg frame rate issue

  3 juillet 2013, par user2529661

  I have been having frame rate issues with ffmpeg. I'm trying to make a mkv file with a raw H.264 input.

  I have to declare a frame rate or it will default to 25 fps, but the text becomes out of sync when I try to set a frame rate with the -r option :

  ffmpeg -r 29.42 -i 2.h264 -i 2.ass -map 0 -map 1 -c copy 2.mkv

  I know the time duration of the H.264 file when I get the frame count using :

  ffprobe -i 2.h264 -show_streams -count_frames

  I can calculate the frame rate and make the mkv file and the text is pretty well synced. This is slow ; it takes about 1 min to process 10 mins of video. My files will be up to 1 hour long and this all has to be done in the back ground from my .net app.

  • Is there a faster way to get the framerate ?
  • Is using ffprobe the best option ?
  • Can I force a duration on the mkv file ?