Any good integrated transcoding solutions for HD

[fyodor]

Has anybody been able to pull off acceptable, semi-reliable transcoding for HD? I've tried the built-in transcoding and played around with the parameters to no avail. It doesn't work about half the time and the quality is very poor given the file sizes.

I've tried evilpenguin's custom plugin and all of my transcoded HD content either has no sound or is out of sync.

Has anybody had any luck using either of these for HD? Are there parameters that can be tweaked for better results?

I'd like to avoid solutions that involve leaving Sage to execute the compression. I am contemplating ditching Sage over my inability to archive anything. Any help would be greatly appreciated.

Thanks
F

[stanger89]

What kind of reductions in size are you expecting? Many broadcasters are already squeezing HD to the bare minimum. More efficient codecs can do better but they're significantly hampered by the artifacts introduced by the broadcast compression.

[fyodor]

I'm expecting something on the order of 1/2 for comparable quality and maybe 1/5 for something still decent and watchable. I'm not getting anything near the results I've seen with other solutions.

[emok]

Are you looking for realtime transcoding while streaming or just the ability to convert existing files to other formats as a batch process?

Niel's webserver plugin recently had transcoding support integrated. It uses vlc as the transcoder and can use a variety of vlc's supplied codecs.

You can run vlc separately to transcode most formats and perhaps setup a batch file to run this process outside of sage.

http://www.videolan.org

[fyodor]

I'd like something launchable from Sage that can transcode shows for archiving. I'm not sure if the webserver does this.

[roxy99]

OT but sometimes HD on my 46" RPTV doesn't look any better than SD on a 36". Like Stranger said, with HD your goal is not to over-compress since its already heavily compressed by the broadcaster.

Eventually I'll get around to incorporating HD compression in my script but I find that the recipe for HD is a whole other ball game. I am leaning towards a script that will convert 1080i to 720p (or even lower for comressibility). It will be de-interlaced and striped of commercials.

You should be getting very good quality from Evil Penguins program though so I would think that you should ask him if there is anything in your config preventing it.

My script will NOT be integrated in Sage unless or until someone writes a plugin. One issue with my script is that it is a resource hog and almost certainly requires a secondary computer to process the mpg.

[fyodor]

EvilPenguin's converter gets good quality, but the audio-video sync is badly off on HD recordings. Actually, it seems to work OK for progressive content, but not for interlaced (1080i).

[roxy99]

Originally Posted by fyodor

EvilPenguin's converter gets good quality, but the audio-video sync is badly off on HD recordings. Actually, it seems to work OK for progressive content, but not for interlaced (1080i).

Is the audio synch consistently off? If so then probably the audio delay factor is wrong. Do you chop out commercials from the Mpg or do you process avi with commercials and then merely skip them? Chopping out the commercials could cause problems at the splice points on the newly compressed de-commercialized avi. My batch file gets around that problem because I frameserve : )

And if progressive content is working fine then probably the 60fps in interlaced encoding is screwing up the timing. You should be able to de-interlace the 1080i with Evilpenguins plugin. Try to aim for a 720p file and don't bother trying for 1080p.