TS Transcode for MVP

[zehd]

Yes, I just tried this out, and from the MVP, everything defaults to .mpg's regardless of the transcode profile you select. Looking at my logs in the MVP Cache folder, it looks like it is over-rideing to Trans2MVP for .mpeg files and overiding to 4ts for .ts files.

That is correct... ZProcess has always been primarily a transcode [NON MPEG] to mpg on the fly transcoder, so it will try to make a playable mpg...

With you guys playing with manual transcoding using conversion profiles, you are trying to get around something I never really focused on. Yes the support was there and then TS files came a long, and everyone started having troubles, mostly because the transcode engines (MEncoder, FFmpeg, VLC etc, couldn't handle the transcodes...

In regards to the output folder, it will take an Output destination when received from GB-PVR. Or commandline.. But It will always default to the standard directories..

[zehd]

That is correct... ZProcess has always been primarily a transcode [NON MPEG] to mpg on the fly transcoder, so it will try to make a playable mpg...

With you guys playing with manual transcoding using conversion profiles, you are trying to get around something I never really focused on. Yes the support was there and then TS files came a long, and everyone started having troubles, mostly because the transcode engines (MEncoder, FFmpeg, VLC etc, couldn't handle the transcodes...

In regards to the output folder, it will take an Output destination when received from GB-PVR. Or commandline.. But It will always default to the standard directories..

I will need some more time before I can settle and then concentrate on what is happening. I know that I am not able to transcode the ample file you sent me, and it looks like a really big animal to deal with...

[Bobins]

Zehd,

The HD TS transcode is not a big problem as not many of my recordings will be HD, The SD TS ones will be 95% of what's recorded so sorting the audio sync is high on the WAFs list of priorities (hence me asking if there was something I could try)

Happy to help/test ideas when you're able to respond.

Appreciate your efforts!!!

[mvallevand]

Bobins because you use mp2 audio in the UK for SD files, what is the problem with the default SD ffmpeg .ts profile that comes with GB-PVR? Nothing really beats -vcodec copy and -acodec copy for quality or speed in creating an mvp compatible SD mpeg. My opinion is if this doesn't work then your input stream is probably at fault.

Martin

[Bobins]

Hi Martin,

The quality of the video or audio isn't the problem whether I'm using the default GBPVR ffmpeg or Zhed's ffmpeg-alt in ZProcess although I couldn't get the default ffmpeg to transcode "on-the-fly" to the mvp.
In all cases in the resultant mpg file the video is about 1.5 seconds behind the audio (i.e. the video is lagging behind).

I've tried various TS files from different channels and all produce the same sync problem. I've tried adding "async 1" to the ffmpeg command line but that seemed to make the video lag even further behind the audio.

The lag looks pretty constant (i.e. not getting worse) as the files play although I can't confirm till at least I can get the start is in sync.

[mvallevand]

Do you mind sending me a link to the SD file too or just upload it to megaupload, rapidshare etc.

Martin

[zehd]

Do you mind sending me a link to the SD file too or just upload it to megaupload, rapidshare etc.

Martin

Martin, I will upload to whurlston's common server and give you the link...

@Bobins. the file you sent was HD. Would you also be able to make a SD file available to either of us

(Maybe Me, and then I will share with Martin)

[Bobins]

Hi Guys,

I've made some progress today. This was driving me crazy as I kept changing things and got inconsistent results so I wrote myself a test schedule and went through it methodically.

If I transcode a SD TS file to mpg manually from the video library using the default ffmpeg and "vcodec copy acodec copy" it plays absolutely fine in PVRX2 however on the MVP the audio sync is out. I get the same result with an autotranscoded file too. I've tried many different recordings, all the same.

I've now created a custom transcode comand line for TS files as the
<AutoConvertTSCommand exe="ZTools\ZProcess2.exe">4ts "{SOURCE_FILE}" {DEST_FILE}</AutoConvertTSCommand>
line in the config.xml seems to be ignored by GBPVR.

With the line
<Conversion name="Zprocess" exe="ZTools\ZProcess2.exe" cmd="4ts {SOURCE_FILE} {DEST_FILE}" targetExtension=".mpg" />
both manual & auto SD TS files transcode successfully and more importantly both play fine on PVRX2 and the MVP.

Next onto HD TS files.

These won't transcode using ZProcess as it doesn't identify the file's parameters properly and tries to transcode with the TRANS2MVP profile.

I've tried manually running ZTranscode and after selecting the file, changed the profile to 4TS. The file transcodes but the video is behind the sound and visually looks in slow motion.

I repeated this but selected the default ffmpeg instead of the ffmpeg-alt and this resulting transcode has correct video & audio in sync.

I changed my auto transcode line to:-
<Conversion name="MPG-MVP2" cmd="-y -i {SOURCE_FILE} -vcodec mpeg2video -b 2400k -acodec mp2 -s 704x576 -f dvd {DEST_FILE}" targetExtension=".mpg" />
and with this line both SD & HD TS files will manually and automatically transcode and play on both PVRX2 and the MVP.
Obviously everything is now using the default ffmpeg.

Now onto "on-the-fly" transcode for the MVP.

With either
<MVPFFmpegTranscodeTS>-y -i "{SOURCE_FILE}" -vcodec mpeg2video -b 2400k -acodec mp2 -s 704x576 -f dvd {DEST_FILE}</MVPFFmpegTranscodeTS>
or
<MVPFFmpegTranscodeTS exe="ZTools\ZProcess2.exe">4ts "{SOURCE_FILE}" "{DEST_FILE}"</MVPFFmpegTranscodeTS>

It is possible to play a SD TS file "on the fly" on the MVP (via its transcode)

Unfortunately, it's not possible to play a HD TS file "on-the-fly" even with the default ffmpeg. You get a brief snatch of output before the end of transcode file is reached. I'm using a quad cpu and the combined core utilisation is 25% although ffmpeg seems to hog 80-90% of one core. It looks to me like the limitation is disk I/O. I tried splitting the source & destination files accross two seperate disks and this allowed 3-4 seconds of output before the play reached the end of the file.

I've also tried reducing the size and bitrate settings but it just won't transcode fast enough.

So conclusions:-

SD TS can be made to work fine in ZProcess
HD TS files have a problem being recognised in ZProcess and when corrected manually, ffmpeg-alt has a problem with transcoding the video.
Lastly, on-the-fly HD transcode is a no-go

Hope this helps Zehd

[zehd]

Hi Guys,

I've made some progress today. This was driving me crazy as I kept changing things and got inconsistent results so I wrote myself a test schedule and went through it methodically.

If I transcode a SD TS file to mpg manually from the video library using the default ffmpeg and "vcodec copy acodec copy" it plays absolutely fine in PVRX2 however on the MVP the audio sync is out. I get the same result with an autotranscoded file too. I've tried many different recordings, all the same.

I've now created a custom transcode comand line for TS files as the
<AutoConvertTSCommand exe="ZTools\ZProcess2.exe">4ts "{SOURCE_FILE}" {DEST_FILE}</AutoConvertTSCommand>
line in the config.xml seems to be ignored by GBPVR.

With the line
<Conversion name="Zprocess" exe="ZTools\ZProcess2.exe" cmd="4ts {SOURCE_FILE} {DEST_FILE}" targetExtension=".mpg" />
both manual & auto SD TS files transcode successfully and more importantly both play fine on PVRX2 and the MVP.

Next onto HD TS files.

These won't transcode using ZProcess as it doesn't identify the file's parameters properly and tries to transcode with the TRANS2MVP profile.

I've tried manually running ZTranscode and after selecting the file, changed the profile to 4TS. The file transcodes but the video is behind the sound and visually looks in slow motion.

I repeated this but selected the default ffmpeg instead of the ffmpeg-alt and this resulting transcode has correct video & audio in sync.

I changed my auto transcode line to:-
<Conversion name="MPG-MVP2" cmd="-y -i {SOURCE_FILE} -vcodec mpeg2video -b 2400k -acodec mp2 -s 704x576 -f dvd {DEST_FILE}" targetExtension=".mpg" />
and with this line both SD & HD TS files will manually and automatically transcode and play on both PVRX2 and the MVP.
Obviously everything is now using the default ffmpeg.

Now onto "on-the-fly" transcode for the MVP.

With either
<MVPFFmpegTranscodeTS>-y -i "{SOURCE_FILE}" -vcodec mpeg2video -b 2400k -acodec mp2 -s 704x576 -f dvd {DEST_FILE}</MVPFFmpegTranscodeTS>
or
<MVPFFmpegTranscodeTS exe="ZTools\ZProcess2.exe">4ts "{SOURCE_FILE}" "{DEST_FILE}"</MVPFFmpegTranscodeTS>

It is possible to play a SD TS file "on the fly" on the MVP (via its transcode)

Unfortunately, it's not possible to play a HD TS file "on-the-fly" even with the default ffmpeg. You get a brief snatch of output before the end of transcode file is reached. I'm using a quad cpu and the combined core utilisation is 25% although ffmpeg seems to hog 80-90% of one core. It looks to me like the limitation is disk I/O. I tried splitting the source & destination files accross two seperate disks and this allowed 3-4 seconds of output before the play reached the end of the file.

I've also tried reducing the size and bitrate settings but it just won't transcode fast enough.

So conclusions:-

SD TS can be made to work fine in ZProcess
HD TS files have a problem being recognised in ZProcess and when corrected manually, ffmpeg-alt has a problem with transcoding the video.
Lastly, on-the-fly HD transcode is a no-go

Hope this helps Zehd

Actually its great information... thanks...

ZProcess is just a go between GB-PVR and ffmpeg (or another transcoder) and so when in doubt, remove it from reference and tweak the command line for default FFmpeg.. Good show..

What this has shown me is:

For your files, the default ffmpeg work great. I should be able to configure ZProcess so that you can do what ever you want, but it doesn't matter until I can get it to KNOW what the dimensions of the input file are...

Just so you know, I'm learning .net. It's cool, and when I look at my VB6 code, I'm starting to scratch my head and wonder why I did things that way...

I suspect I will be changing some of the profiles scheme, so that aside from the Trans2MVP profile, you can set up a separate profile for each type of video/audio combination you come across regularly

I would really like an SD sample from you, so that I can be sure that ZProcess is flipping back and forth well...

[mvallevand]

I would really like an SD sample from you, so that I can be sure that ZProcess is flipping back and forth well...

Ditto. 30 Mbs will be fine. Sub even wrote a little utility to get a sample from an existing file http://forums.gbpvr.com/showpost.php?p=3...ostcount=2

Martin