Another Round of Samples and Tests

Thanks to all of the advice in the comments of the last post about filling in gaps in the FATE test coverage, I have staged 11 new FATE test specs:

Regarding that group of 6 Sun raster files, it’s interesting to note that the 24-bit raw Sun raster file sample is smaller than the 24-bit RLE version.

I encountered a few problems with the suggestions from the last post. Among them:

  • ami_stuff came through with a sample of a Fibonacci-encoded 8svx file. Unfortunately, it’s attached to a bug report because it’s not presently working. Test not staged.
  • I downloaded the free Command & Conquer games from EA and looked into Tiberian Sun specifically. It looks like all the game resources are wrapped up into .MIX files. Not a big deal– I wrote a program years ago to take these apart. Unfortunately, the files are in a different MIX file format, apparently. So I’m still stuck on trying to get the audio samples I need.
  • Carl Eugen pointed to a sample of Blu-Ray PCM (mpegts+h264+++trunc_read_packet_loop.m2ts). Thing is, the file has 9 streams; the pcm_bluray stream is right in the middle. I still don’t know how to tell FFmpeg to select that stream.
  • On the subject of files that have more than 1 audio and 1 video stream, most of these samples with subtitles have the same problem as encountered with the last item– I don’t know how to tell FFmpeg to process the subtitle stream. In fact, the sample from the previous item also has 4 pgssub streams. How do I select one? And will I be able to cleanly mux a subtitle stream into the framecrc format?

I think FFmpeg’s -map option may hold the key. But I’m a little too tired and annoyed to read the source code which I’m certain is the only true documentation for how it works.

4 thoughts on “Another Round of Samples and Tests”

  1. Jonathan Wilson

    Go to http://xhp.xwis.net/ and download XCC mixer. It can read all those mix files and grab any audio (or other multimedia) you want.

    I have been a longtime modder of the C&C series games and know a LOT about them. One of the few things I dont have any knowledge on is the EALayer3 MP3-derived codec :(

  2. Carl Eugen

    ffmpeg -vn -t 2 -i mpegts+h264+++trunc_read_packet_loop.m2ts -map 0.4 -f crc –
    Instead of -t 2, you could also cut the sample accordingly to stop FFmpeg from reading an incomplete pcm packet.

  3. Reimar

    framecrc handles subtitle streams just fine.
    However it still won’t work like with audio and video because there is no “raw” format for subtitles.
    Which is why my suggestions involved transcoding the subtitles.
    Of course the disadvantage is that like that you will always test a decoder and a encoder together (though actually the same is true in the other case, it’s just that the “raw” encoders are very unlikely to break).

  4. Multimedia Mike Post author

    @Reimar: The next version of FATE will better support the transcoding testing method– one test for encoding/muxing and a subsequent test for demuxing/decoding. That should take care of much of the remaining 40% of the FATE test coverage. For now, I’ve been trying to fill in stuff for which we only have decoders or demuxers.

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