Updates on the 6200c

May 18, 2007

A while back I reported about my experiences with the ProCaster 6200c DVBc PVR device. I’ve now done a bit more research into free playback, transcoding and editing solutions and here are some results:

  • VLC will not play back the files. All you get is noise and no audio.

  • ffmpeg/ffplay doesn’t know what to do with them either. It recognizes the audio track, but only sees a subtitle track where the video data should be.

  • MPlayer plays back the files fine, just without subtitles. This is really cool and should also mean that mencoder will work.

  • Then I discovered these guys and a tool called ProjectX which seems to be somesort of crazy utility for different PVR formats. The remarkable thing about it is that it actually works, on a Mac, no less, allowing you to extract and demux video, audio and subtitle streams from AVR files. It even has pretty good editing capabilities with which you can specify more than one cut point at once (something that many simple editors don’t actually do) so in theory you could use this to manually mark out ads, demux everything (it seems that subs are not exported during a partial/edited demux) and send the output for encoding to some other app.

It seems AVR is much more than a simple MPEG2 container I thought it to be before. It’s more like a VOB, containing anything from video and subtitles to alternate audio tracks. Another interesting discovery I made while playing with ProjectX was that DVB actually supports text-to-speech. Here’s a sample of the audio track of this clip. Notice how it’s overlaid on top of the original audio.

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  • D-Vision 3 - no contact. Not with the AVR’s or even the demuxed m2v’s. This is surprising because it’s supposed to be a mencoder frontend which in turn is based on MPlayer. Quite frankly, I don’t understand this program anymore. It used to be good for stitching AVIs and stuff but it just keeps getting weirder and weirder with every release.

  • ffmpegX will surely be able to handle the demuxed material, but I just don’t feel like messing around with it tonight. Probably won’t handle avr directly since ffmpeg didn’t.

  • mencoder (compiled from SVN), as guessed can crosscode the AVR directly, still no subtitles, but it’ll have to do for now:

    ./mencoder -oac mp3lame -ovc xvid -xvidencopts bitrate=1000 ~/test.AVR -o test.avi

This turned out to be a pretty interesting little experiment. It makes me think there’s really no tool out there specifically for the Mac that does what I need. ProjectX was a really nice surprise, but since the biggest motivator for me in all of this is archival (the HD on the PVR is just filling up), then it’s not quite what I need. Ideally we’d have a tool into which you through a batch of AVR’s straight off the box, select the subtitle track and have it cut out the ads and encode a typical ~1mbit/s 720i high-quality XviD out of it. Even an easy-to-use AVR -> XviD/AVI batch-encoder would be a step in the right direction.

Maybe I’ll just have to try and make one…