I was inspired by the recent 'Single most frustrating thing about MythTV...' discussion (plus the fact that this is exactly what I've been spending most of my MythTV hacking time on) to try to direct some of this energy into identifying and improving the most likely candidates. Hopefully in this way those of us that are not C++ hackers can still meaningfully contribute without just whining about features we want.
So anyway, here's a summary of what I've found. I'm sure it's not an all-encompasing list, so add yours to this thread if you like: Problem statement: I want to record my PVR-x50 MythTV-recorded stuff on a DVD that a regular DVD player can play. Oh, and of course I want to cut out commercials too. Possible solutions: There isn't anything yet that is reliable and foolproof. However, this one is probably the closest to "fire and forget" so far: mythtvburn http://mysettopbox.tv/phpBB2/viewtopic.php?t=2132&start=330&postdays=0&postorder=asc&highlight= It's a lot of work to read through 20+ pages of posts in that thread to figure out all of the issues. You'll wind up: o making sure you're recording in the right format and size (e.g. 720x480 MPEG2-PS for NTSC) so you don't have to transcode o getting ths cvs version o getting the options to transcode right to eliminate blue and/or upside-down thumbnails o making modifications to paths to make it work on your distro (I'm using FC2) o installing nuvexport, XVfb, avidemux2, and tons of other prereqs Last time I rebuilt my Myth box (when I moved to FC2 from Debian), I set aside a 20G /scratch partition just so I could mess with all of this stuff without putting my ability to record shows in jeopardy. It takes a lot of space to do this, so consider doing something similar. If I'm remembering all of the steps, here's what's going on behind the scenes once you kick this off: 1) Use your mythfrontend to convert the commercial skip list to a cut list (and edit it to correct for errors) 2) Use MythWeb to select the shows to burn to DVD and start the script 3) avidemux2 will index the .nuv files for those shows 4) avidemux2 will split the MPEG2-PS contents of the .nuv files into component .m2v video and .mp2 audio, using the cutlist to clip out commercials (using Xvfb to hide the gui from you) 5) lvemux will re-combine the video and audio into an (MPEG2) .mpg file 6) (repeat above for other shows going on the same DVD) 7) transcode will extract a bunch of JPEG thumbnails for the DVD menu 8) these wind up being composited together and converted to .png and back (I think) 9) the XML menu structure "script" is created to feed to dvdauthor 10) mplex combines the menu music you picked and the JPEG menu image into a .mpg 11) spumux combines the movie and the XML into the DVD menu 12) dvdauthor puts it all together into the DVD/VIDEO_TS dir structure 13) you can preview now with xine dvd://path/to/["DVD" folder] 14) use growisofs to write the DVD folder direct to your DVD+/-R[W] without building an .iso first. As you can see, there's a lot going on, and things can fail at any of these steps. I don't trust my system to do all of this by itself yet; I'm manually doing the commercial cutting and a/v splitting because avidemux2 keeps failing on me at that point if I have it scripted, but if I do it myself it seems to work. Even so, when I get all done and preview the DVD, it seems like the audio and video get further and further out of sync over time. I wonder if all of those warnings from avidemux2 about the video being 33 ms off from the audio are adding up to create larger and larger a/v sync differences at each cutpoint? Having said all that about mythtvburn, there are other ways too: nuvexport 1) Use nuvexport's mpeg2 -> mpeg2 cut option to export and commercial-cut your shows from Mythtv into standalone .mpg files. (which is using the same avidemux index, split/cut, lvemux re-combine process as above, all with Xvfb to hide the gui) 2) Use dvdstyler or something else to build a DVD menu and burn (via growisofs?) to DVD I did this and still had the "increasingly out of sync over time" problem (which is why I think it's avidemux2/lvemux doing this). In any case, this is a pretty manual command-line-driven process, so it may not appeal to you as much. windows/macintosh I'm sure there's some process by which you could copy the .nuv files to a windows box (peraps via samba on your mythtv backend), and use an entirely external-to-myth process to edit, create a menu, and burn. I have no idea what it is. Maybe someone will offer up their step-by-step windows-based solution. As for the macintosh option, I've fought with this and as far as I can tell it's not possible to do without buying Apple's MPEG2 import component for $30, and possibly also QuickTime Pro for another $30, then using some utility like MPEG Streamclip to convert to DV format (remembering to split into lots of chunks since iMovie can't handle large files), then manually edit in iMovie and transfer to iDVD for [mostly manual] menu creation and burning. I haven't been desperate enough yet to spend the $60 to see if this might be workable... maybe someone else on the list took this approach and can vouch for how well it does or doesn't work. Even if it did work, I imagine it would still be agonizingly slow and require lots of hands-on effort and babysitting. Video Quality Once you get one of these processes working, you still may not be satisfied with the results. For example, I don't have my PVR-350 TV-out working yet, so I'm using an nVidia GeForce 2mx S-video output to my TV for now. I'm reasonably happy with the video quality given that my analog cable input is pretty bad to start with. When I play back recorded shows on my Myth box, the video output seems to smooth out some of the imperfections and is reasonable. When I burn to DVD however the result, when played on my DVD player, looks terrible. It's not so bad you can't watch it, but it's definitely more like VHS quality and visibly worse than MythTV's own ouput. I had thought that since I was recording in MPEG2-PS 720x480, and I wasn't transcoding to something else to burn to DVD that I should get pretty similar output from my DVD player. Maybe something is going on with the bitrate that I don't understand and don't have configured correctly. But anyway, after going through all of this pain and getting relatively poor quality output, it seriously makes me reconsider just burning cut MPEG2 (or transcoded MPEG4) files to a data-DVD and forgetting about DVD-video compatibility. Maybe it's more cost/time effective to just build a small mythfrontend for my car that just has mythvideo reading from the DVD device and use that for trips instead of the portable DVD player. Conclusion My personal feeling is that if you're dying for this feature, the best thing you can do is to head over to the mythtvburn thread on mysettopbox.tv and work with everyone else there to make that work (including fighting with all of the components, shell scripts, etc.). That seems like the shortest path to the stated goal. Once the "back end" part of that is working reliably it should be easier to get someone interested in making an actual Myth module front-end for it. -- Dave Caplinger
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