HD-PVR H.264 to Mpeg2 commercial skip Question

[Eckwell]

Does anyone know of the best way to transcode the H.264 from teh HD-PVR to Mpeg2 so that comskip can "see" it?

I was just thinking... what is the transcode could begin soon after the H.264 file has started recording so that both processes happen in parallel? just a thought?

Or perhaps have the H.264 file "Play" and be recorded in Mpeg2?

I know it sounds silly to go backwards, but I am just looking for a commercial skip option.

[erik]

Neither mencoder or ffmpeg can run while recording at the moment.
It should be possible to port the read-while-recording functionality of comskip to both of them.
Is either of the able to do the transcoding of h264 at the moment?
At what speed if possible?
Comskip should be able to process with good quality when the converted output is 320x200 so encoding should not take much capacity

[sleonard]

By the time someone could get something working like this Jere will have H.264 support in ShowAnalyzer.

S

[Brent]

Originally Posted by sleonard

By the time someone could get something working like this Jere will have H.264 support in ShowAnalyzer.

S

Pretty sure we'll see h.264 commercial detection in ShowAnalyzer first and then Comskip. I worry a little about how powerful a processor one would need in the server to do the processing though.

[ghostlobster]

Has anyone talked to Andy (http://www.babgvant.com) about this? Andy is the guy who developed DVRMSToolbox for MCE and he did an incredible job with it. I know that he had made DTb mencoder aware, but I don't know much else....other than the fact that he is becoming as disenchanted with MCE as I was and is considering Sage himself. He would be a very welcome addition to the SageTV community.

[Brent]

Originally Posted by ghostlobster

Has anyone talked to Andy (http://www.babgvant.com) about this? Andy is the guy who developed DVRMSToolbox for MCE and he did an incredible job with it. I know that he had made DTb mencoder aware, but I don't know much else....other than the fact that he is becoming as disenchanted with MCE as I was and is considering Sage himself. He would be a very welcome addition to the SageTV community.

I would love to see Andy join the SageTV community. He'd be a very welcome addition to the growing ranks of developers around here. If theres anything we can do to help convince him let us know.

[ghostlobster]

Maybe we can all chip in and buy him a pony?

[Brent]

Originally Posted by ghostlobster

Maybe we can all chip in and buy him a pony?

I was thinking of something a little smaller

[babgvant]

Originally Posted by ghostlobster

Maybe we can all chip in and buy him a pony?

While my kids might like a pony, I don't have the backyard for it

Re. the topic at hand, I think your best best is to use DirectShow to reencode the file to mpeg as it is recording. The most recent version of DVRMSToolbox (DTB) supports alternate file type (i.e. non-dvr-ms files) exactly for this type of scenario. You'd probably need a pretty modern box to do it in a timely way though.

If this is something you'd like to pursue let me know and I can outline the steps.

[Brent]

Originally Posted by babgvant

While my kids might like a pony, I don't have the backyard for it

Re. the topic at hand, I think your best best is to use DirectShow to reencode the file to mpeg as it is recording. The most recent version of DVRMSToolbox (DTB) supports alternate file type (i.e. non-dvr-ms files) exactly for this type of scenario. You'd probably need a pretty modern box to do it in a timely way though.

If this is something you'd like to pursue let me know and I can outline the steps.

First let me say, it's good to see you here babgvant! I'm a fan of your work and welcome your input or even better your joining the SageTV community.

And yes, I'm interested in the steps when you have time. Thanks!

[babgvant]

Originally Posted by Brent

First let me say, it's good to see you here babgvant! I'm a fan of your work and welcome your input or even better your joining the SageTV community.

And yes, I'm interested in the steps when you have time. Thanks!

I'm not an official member yet, but I'm happy to help anywhere I can.

You'll need the latest rev of DTB to have the FW support non-dvr-ms files, but the rest of it will work with previous versions.

1) Create a stub graph file with the filters necessary to encode a file to mpeg using GraphEdit. I used the ArcSoft one in the graph, but you could just as easily use AVIVO. Any intermediate filters (like a preferred decoder) will need to be added to the graph if they won't get added via IC. You can test this by creating the stub and selecting "Render File" to see what gets added automatically.


2) DL this profile and point the second action at your stub grf.

3) Then it's just a matter of running dvrmstompeg.exe against your h.264 file with the right args (/if=filetoconvert.ext /of=mpegfilepath.mpg /act=filetompeg) you probably want to output the mpeg to whatever folder is required so comskip detects it and will start processing it.

[erik]

Do you downscale the MPEG output? Comskip would only need 320x200 to do its job

[babgvant]

Originally Posted by erik

Do you downscale the MPEG output? Comskip would only need 320x200 to do its job

a scaler filter could be added in the stub, but I don't know if it would join the graph automatically.

there is an action in DTB that allows more control over the graph building process, but it would have to be modified to work with non-dvr-ms source files.

[QueOnda]

Hello guys. This would be cool. Are you thinking of leaving the H.264 file and just converting to a small Mpeg (leaving the H264) then having comskip do it's job, then deleting the mpeg after the output files from comskip are there??

[Sam]

Originally Posted by babgvant

You'll need the latest rev of DTB to have the FW support non-dvr-ms files, but the rest of it will work with previous versions...

Can you be a little more explicit? When I try version 1.2.1.2 on my WinXP machine, it says it requires Vista. I also downloaded 1.1.0.8 for XP, but can't figure out how to do this.

I've also never used GraphEdit. Can someone please be a little more explicit on the exact steps needed to make this work?

[Sam]

As an alternative to dynamically converting the H264 file to mpeg2 for the sake of ComSkip or SA, I thought of another method which should have very low overhead on the PC because it avoids the need to recode.

Many / most of us with a HD-PVR will likely have an analog capture video source which is being idled by the HD-PVR. It the STB which feeds the HD-PVR also had its S-Video (or composite) output feed the analog capture source concurrently, it would do the mpeg2 encoding for us.

If the analog video source were removed from Sage setup, is there a relatively easy way using Studio to make an add-in which would watch for recordings on the HD-PVR source and concurrently start/stop an analog capture? It would not be necessary to tune the channel, because the STB would already be tuned.

Or using DirMon2, would there be a way to just start an analog capture from a command line? (Maybe using SageTVTranscoder.exe with the -gd option?) I assume this would cause the analog capture to lag behind the H264 capture though, so the timeline would probably be off by the same time it took for DirMon2 to recognize the new file and start the second recording.

[babgvant]

Originally Posted by QueOnda

Hello guys. This would be cool. Are you thinking of leaving the H.264 file and just converting to a small Mpeg (leaving the H264) then having comskip do it's job, then deleting the mpeg after the output files from comskip are there??

yes

[babgvant]

Originally Posted by Sam

Can you be a little more explicit? When I try version 1.2.1.2 on my WinXP machine, it says it requires Vista. I also downloaded 1.1.0.8 for XP, but can't figure out how to do this.

I've also never used GraphEdit. Can someone please be a little more explicit on the exact steps needed to make this work?

The method I talked about will work with some filters but it's highly dependent on IntelligentConnect working, and it won't support resizing unless the encoder does the scaling. So it should work, but it's not a perfect solution.

I'm modifying the action that allows an explicit graph to build in DTB to support non-dvrms files. When it's ready I'll provide everything to make it work (stub, profile, directions), assuming I can get it going with a free set of filters (probably AVIVO). I've got a test file, but I didn't have time to mess over the weekend; hopefully tonight.

1.2.x.x is intended for Vista because one of the features specifically targets the WMC; I'll probably remove this requirement if I replatform on Sage.

[Sam]

Originally Posted by babgvant

When it's ready I'll provide everything to make it work (stub, profile, directions)...

OK; I'll be patient.

[Eckwell]

This sounds like a great possibility... thank you so much for trying to come up with a working solution. If you need assistance with testing, etc, I can give it a try too...