I haven't got as far as adding a trick to the mymedia server to kick off the transcoding, I've just been starting it manually. It should be fairly easy for anyone with some Python knowledge to do, but I've been busy with other things.
I think this is the command line that worked for NASA TV, but I'm not absolutely positive. I started playing with the fps and the video size at one point without success, so I don't know where I left off.
vlc -I dummy --mms-caching 0 http://www.nasa.gov/55644main_NASATV_Windows.asx vlc://quit --sout="#transcode{threads=2,width=320,height=240,fps=30,vcodec=h264,vb=256,venc=x264{aud,profile=baseline,level=30,keyint=30,bframes=0,ref=1,nocabac},acodec=aac,ab=96}:duplicate{dst=std{access=livehttp{seglen=10,delsegs=true,numsegs=5,index=F:\Roku\Media\Video\mystream.m3u8,index-url=http://192.168.1.103:8001/media?name=nasa-####.ts&key=video},mux=ts{use-key-frames},dst=F:\Roku\Media\Video\nasa-####.ts}}"
I'll break it down as much as I'm familiar with it. One important thing is to make sure 'acodec' is set to 'aac'. That's the only audio format the Roku supports for HLS. The paths should be obvious. You'll want to change "F:\Roku\Media\Video" to your video path and the ip address to your myMedia server ip. The other parts I know about are the 'seglen' which is how long each segment is in seconds. The spec and/or Apple recommends 10 to 15 seconds. 'delsegs=true' will allow vlc to delete the segments as they're no longer needed. 'numsegs=5' gives the number of segments that will be present in the m3u8 file at any one time and the number of segments that will be on the disk before they're automatically deleted.
This command should convert an entire file and leave all the segments in the m3u8 file and on the disk.
vlc --verbose 2 --extraintf logger -I dummy --mms-caching 0 "%1" vlc://quit --sout="#transcode{threads=2,width=320,height=240,fps=30,vcodec=h264,vb=256,venc=x264{aud,profile=baseline,level=30,keyint=30,bframes=0,ref=1,nocabac},acodec=aac,ab=96}:duplicate{dst=std{access=livehttp{seglen=10,delsegs=false,numsegs=0,index=F:\Roku\Media\Video\mystream.m3u8,index-url=http://192.168.1.103:8001/media?name=hls/file-####.ts&key=video},mux=ts{use-key-frames},dst=F:\Roku\Media\Video\hls\file-####.ts}}"
Replace "%1" with the name of the video file. The double quotes worked under windose; other OSs might need single quotes.
Give me a day or so to get the myMedia client/server stuff together. I'm very close to putting the finishing touches on a new release and I don't want to switch back to the experimental HLS version quite yet.
-JT
Roku Community Streaming Expert
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