title: Converting Real Media with ffmpeg
body: <p>I have a number of old crusty Real Media files I need to convert and was hoping to write a script to batch process them. I'm able to do a Real Media -> AVI conversion with FFMpegX, but when I try to replicate the conversion with ffmpeg, it always errors out with something like:</p>
  
  <pre><code>[avi @ 0x10084fa00] Too large number of skipped frames 117425 &gt; 60000
  </code></pre>
  
  <p>It may have something to do with the funky format of these Real Media files:</p>
  
  <pre><code>Duration: 01:28:23.42, start: 0.000000, bitrate: 448 kb/s
      Stream #0:0: Data: none, 32 kb/s
      Stream #0:1: Data: none, 192 kb/s
      Stream #0:2: Audio: sipr (sipr / 0x72706973), 8000 Hz, mono, flt, 6 kb/s
      Stream #0:3: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 13 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:4: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 8 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:5: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 5 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:6: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 27 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:7: Audio: cook (cook / 0x6B6F6F63), 22050 Hz, mono, fltp, 32 kb/s
      Stream #0:8: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 192 kb/s, 30 fps, 30 tbr, 1k tbn, 1k tbc
      Stream #0:9: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 136 kb/s, 30 fps, 30 tbr, 1k tbn, 1k tbc
      Stream #0:10: Audio: sipr (sipr / 0x72706973), 8000 Hz, mono, flt, 6 kb/s
      Stream #0:11: Audio: sipr (sipr / 0x72706973), 8000 Hz, mono, flt, 6 kb/s
      Stream #0:12: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 13 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:13: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 13 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:14: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 13 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:15: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 5 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
  </code></pre>
  
  <p>Does anyone have any tips on either how to find out what FFMpegX is doing to make the conversion work, or a better way to go about using ffmpeg to do this?</p>
  
  <h3>EDIT</h3>
  
  <p>Including the ffmpeg command (thank you to @Mondain for teaching me about the stream mapping!) and output:</p>
  
  <h3>Command:</h3>
  
  <pre><code>ffmpeg -i cc121307pm.rm -map 0:8 -map 0:7 -c:v libx264 -c:a libfaac -b:a 32k test.avi
  </code></pre>
  
  <h3>Output:</h3>
  
  <pre><code>ffmpeg version 1.2.1 Copyright (c) 2000-2013 the FFmpeg developers
    built on Aug  7 2013 12:29:30 with gcc 4.2.1 (GCC) (Apple Inc. build 5664)
    configuration: --prefix=/usr/local/Cellar/ffmpeg/1.2.1 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-nonfree --enable-hardcoded-tables --enable-avresample --enable-vda --cc=/usr/bin/gcc-4.2 --host-cflags='-Os -w -pipe -march=core2 -msse4.1 -mmacosx-version-min=10.6' --host-ldflags=-L/usr/local/lib --enable-libx264 --enable-libfaac --enable-libmp3lame --enable-libxvid
    libavutil      52. 18.100 / 52. 18.100
    libavcodec     54. 92.100 / 54. 92.100
    libavformat    54. 63.104 / 54. 63.104
    libavdevice    54.  3.103 / 54.  3.103
    libavfilter     3. 42.103 /  3. 42.103
    libswscale      2.  2.100 /  2.  2.100
    libswresample   0. 17.102 /  0. 17.102
    libpostproc    52.  2.100 / 52.  2.100
  [rm @ 0x10180f200] Unsupported stream type 00000265
  [rm @ 0x10180f200] Unsupported stream type 00000652
  [rm @ 0x10180f200] max_analyze_duration 5000000 reached at 5004000 microseconds
  Input #0, rm, from 'input.rm':
    Metadata:
      File ID         : 41deac0f-94fb-3595-325c-c717943bc532
      Content Rating  : (PICS-1.1 "http://www.classify.org/safesurf" labels comment "RealProducer Plus 8.5.0.200 Windows" ratings (SS~~000 1))
      Modification Date: 12/13/2007 16:26:16
      Generated By    : RealProducer Plus 8.5.0.200 Windows
      Keywords        : 
      Abstract        : 
      Target Audiences: 28K Modem (20 Kbps);56K Modem (34 Kbps);256K DSL/Cable Modem (225 Kbps);
      Video Quality   : Normal Motion Video
      Audio Format    : Voice Only
      Creation Date   : 12/13/2007 14:57:49
      ASMRuleBook     : #($Bandwidth &lt; 15000),Stream2Bandwidth = 6500, Stream3Bandwidth = 5499;#($Bandwidth &gt;= 15000) &amp;&amp; ($Bandwidth &lt; 20000),Stream2Ba
      title           : 
      author          : 
      copyright       : ?2007
      comment         : 
    Duration: 01:28:23.42, start: 0.000000, bitrate: 448 kb/s
      Stream #0:0: Data: none, 32 kb/s
      Stream #0:1: Data: none, 192 kb/s
      Stream #0:2: Audio: sipr (sipr / 0x72706973), 8000 Hz, mono, flt, 6 kb/s
      Stream #0:3: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 13 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:4: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 8 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:5: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 5 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:6: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 27 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:7: Audio: cook (cook / 0x6B6F6F63), 22050 Hz, mono, fltp, 32 kb/s
      Stream #0:8: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 192 kb/s, 30 fps, 30 tbr, 1k tbn, 1k tbc
      Stream #0:9: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 136 kb/s, 30 fps, 30 tbr, 1k tbn, 1k tbc
      Stream #0:10: Audio: sipr (sipr / 0x72706973), 8000 Hz, mono, flt, 6 kb/s
      Stream #0:11: Audio: sipr (sipr / 0x72706973), 8000 Hz, mono, flt, 6 kb/s
      Stream #0:12: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 13 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:13: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 13 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:14: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 13 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
      Stream #0:15: Video: rv20 (RV20 / 0x30325652), yuv420p, 320x240, 5 kb/s, 15 fps, 15 tbr, 1k tbn, 1k tbc
  [libx264 @ 0x101889c00] using cpu capabilities: MMX2 SSE2Fast SSSE3 FastShuffle SSE4.1 Cache64
  [libx264 @ 0x101889c00] profile High, level 1.3
  Output #0, avi, to 'test.avi':
    Metadata:
      File ID         : 41deac0f-94fb-3595-325c-c717943bc532
      Content Rating  : (PICS-1.1 "http://www.classify.org/safesurf" labels comment "RealProducer Plus 8.5.0.200 Windows" ratings (SS~~000 1))
      Modification Date: 12/13/2007 16:26:16
      Generated By    : RealProducer Plus 8.5.0.200 Windows
      Keywords        : 
      Abstract        : 
      Target Audiences: 28K Modem (20 Kbps);56K Modem (34 Kbps);256K DSL/Cable Modem (225 Kbps);
      Video Quality   : Normal Motion Video
      Audio Format    : Voice Only
      Creation Date   : 12/13/2007 14:57:49
      ASMRuleBook     : #($Bandwidth &lt; 15000),Stream2Bandwidth = 6500, Stream3Bandwidth = 5499;#($Bandwidth &gt;= 15000) &amp;&amp; ($Bandwidth &lt; 20000),Stream2Ba
      INAM            : 
      author          : 
      ICOP            : ?2007
      ICMT            : 
      ISFT            : Lavf54.63.104
      Stream #0:0: Video: h264 (H264 / 0x34363248), yuv420p, 320x240, q=-1--1, 30 tbn, 30 tbc
      Stream #0:1: Audio: aac ([255][0][0][0] / 0x00FF), 22050 Hz, mono, s16, 32 kb/s
  Stream mapping:
    Stream #0:8 -&gt; #0:0 (rv20 -&gt; libx264)
    Stream #0:7 -&gt; #0:1 (cook -&gt; libfaac)
  Press [q] to stop, [?] for help
  [rm @ 0x10180f200] DATA tag in middle of chunk, file may be broken.
  Truncating packet of size 775215378 to 283607526
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 686581284 to 279055389
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 845942319 to 279042877
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 519635011 to 279040757
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 302013449 to 260425302
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 671112232 to 260422550
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 670137329 to 260371048
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 674387680 to 260336787
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 698852899 to 260336757
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 881600768 to 260281240
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 623325768 to 241694111
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 273397034 to 241679920
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 245534365 to 241615319
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 264614026 to 220525004
  [rm @ 0x10180f200] Impossibly sized packet
  [rm @ 0x10180f200] DATA tag in middle of chunk, file may be broken.
  Truncating packet of size 637535515 to 219973842
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 432193588 to 219973831
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 286760544 to 219962162
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 1070610764 to 219737624
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 259875548 to 219371853
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 362059391 to 219371844
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 885179606 to 219371833
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 587434829 to 206214002
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 816942211 to 165623435
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 471624979 to 113266905
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 674059889 to 113266894
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 459361272 to 113253548
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 637535515 to 91792709
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 432193588 to 91792698
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 286760544 to 91781029
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 157876310 to 91505934
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 469953408 to 91505925
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 260215377 to 91486921
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 877425642 to 91335612
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 259887697 to 91322050
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 885071836 to 91245341
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 264614182 to 90930431
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 811350015 to 90930422
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 128974975 to 90713958
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 801151589 to 89195724
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 654645420 to 85989435
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 184860915 to 85989426
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 1072093904 to 85980304
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 907644163 to 85521587
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 187973624 to 52762203
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 315276941 to 52762157
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 947559309 to 23894660
  [rm @ 0x10180f200] Impossibly sized packet
  Truncating packet of size 183681448 to 2582872
  [rm @ 0x10180f200] Impossibly sized packet
  input.rm: Input/output error
  frame=    0 fps=0.0 q=0.0 Lsize=      10kB time=00:00:00.00 bitrate=N/A    
  video:0kB audio:0kB subtitle:0 global headers:0kB muxing overhead inf%
  Output file is empty, nothing was encoded (check -ss / -t / -frames parameters if used)
  </code></pre>