Comskip Questions

[mvallevand]

I am doing preliminary work on mvpmcx2 in case Syabas provides some help and I have got some questions on comskip and will need a lot of help from several of because I am not going to run comskip on my own files.

1. Sub, are there any gbpvr major issues in streaming mpeg-ts to the MVP with or without comskip ? I know the mvp only supports mpeg-ps so the parser might not even work. I am not planning on supporting a solution solely for a cyberlink mux to mpeg-ps.

2. How well is comskip working on HD mpeg-ts files for you in PVRx2?

3. Generally is it really worth supporting comskip? At least for HD I've heard it takes a really long time, and it makes the computer work and the software support isn't perfect, especially for h264 files. I am not even sure there is comskip for HD PVR files.

Samples needed to proceed. This is where I need the community's help. Several of your are going to need to provide me with 30 minute or longer samples with lots of commercial breaks of the following with a comskip file already made. I will even accept it from rapidshare and fight the cats, you need to provide the file and I will download.

The easy one

-mpeg2-ps analog capture (NTSC)

Plus the following digital in both mpeg-ps (muxed) and mpeg-ts formats.

-SD with mp2 audio (DVB)
-SD with ac3 audio (QAM)
-HD with mp2 audio (DVB)
-HD with ac3 audio (QAM/ATSC)
-h264 with aac (DVB) *
-h264 with aac (HD PVR) *

Thanks a lot.

Martin

* currently not available.

[erik]

Comskip can not process H264
You should not try to run Comskip on files shorter then 30 minutes because you will get bad results.

[wtg]

Generally is it really worth supporting comskip? At least for HD I've heard it takes a really long time

Yes, I think so. Certainly people enjoy the feature. While HD does take longer Erik created a special HD version that cuts down the time a great deal. Additionally, many people watch their recorded shows days later so there's benefit even if it does take a long time to process.

Samples needed to proceed. This is where I need the community's help. Several of your are going to need to provide me with 30 minute or longer samples with lots of commercial breaks of the following with a comskip file already made.

Do you really need long samples to test? The comskip .txt file is a simple format easy to fabricate, and so I would think you could test with 5 minute sample videos with a few manually created commercial break. In other words, you could create a comskip text file that show commercial breaks at 1 min, 2 min, 3 min and 4 min, each 15 seconds long and test your positioning and streaming logic.

Regardless, I should be able to make some HD samples w/AC3 audio available for you, long or short. Work is killing me right now, but by the weekend I'll email you some login info for my FTP server and provide you some samples.

[wtg]

Comskip can not process H264.

But is this a work in progress Erik? *crosses fingers*

[erik]

[sub]

1. Sub, are there any gbpvr major issues in streaming mpeg-ts to the MVP with or without comskip ? I know the mvp only supports mpeg-ps so the parser might not even work. I am not planning on supporting a solution solely for a cyberlink mux to mpeg-ps.

I'm not sure. I suspect the existing MVP logic would currently work ok with transport streams. The PTS values are stored the same way for both types of diles.

2. How well is comskip working on HD mpeg-ts files for you in PVRx2?

As mentioned above, our HD system isnt compatible with Comskip at this stage, so I cant really give any feedback on this.

3. Generally is it really worth supporting comskip? At least for HD I've heard it takes a really long time, and it makes the computer work and the software support isn't perfect, especially for h264 files. I am not even sure there is comskip for HD PVR files.

I think having comskip support be pretty high on a lot of peoples wish lists, so if we found a way then I think it'd be nice to have it working.

[mvallevand]

Do you really need long samples to test? The comskip .txt file is a simple format easy to fabricate, and so I would think you could test with 5 minute sample videos with a few manually created commercial break. In other words, you could create a comskip text file that show commercial breaks at 1 min, 2 min, 3 min and 4 min, each 15 seconds long and test your positioning and streaming logic.

I do want to test with the break points in the correct spot and I want to confirm that the transition is correct since if it stops too early or starts too late it isn't worth. If I can do this it will mean mvpmcx2 logic is controlling the demux and this can be finicky.

I want a longer sample so I only gather this once. That should give me short and long pauses and allow me to jump by time through the file too.

Martin

[-stattik-]

2. How well is comskip working on HD mpeg-ts files for you in PVRx2?

Comskip works great with HD TS files.

3. Generally is it really worth supporting comskip?

I run Comskip in parallel while recording HD shows. I can record/comskip up to 3 concurrently with a AMD X2 4200+. (And this is without the HD enhancements that erik added.) The cuts are highly accurate.

MPG and TS files are not the only files that I use with comskip. After comskip has processed a TS/MPG file, I sometimes compress it into a MKV container with x264 and aac. When playing back this file in GBPVR, the commercials are still marked and automatically skipped while watching. I can provide some samples if needed.

Samples needed to proceed.

-mpeg2-ps analog capture (NTSC) This will be about 1GB in size.

Plus the following digital in both mpeg-ps (muxed) and mpeg-ts formats.

-HD with ac3 audio (ATSC) This will be about 3GB in size.


Currently comskip support is one of the last things needed to convince the wife to switch to the PCH.

[mvallevand]

--stattik-- Those sizes are about right so if you can't provide them online PM me for my address. I'm surprised that comskip works with mkv files but It is not something I expect that will be support by native support in mvpmcx2 since sub would have to demux to m2ts on the fly and you'd lose navigation control.

Martin

[-stattik-]

--stattik-- Those sizes are about right so if you can't provide them online PM me for my address. I'm surprised that comskip works with mkv files but It is not something I expect that will be support by native support in mvpmcx2 since sub would have to demux to m2ts on the fly and you'd lose navigation control.

Martin

Comskip doesn't run on the MKV files. GBPVR reads the EDL files generated by comskip(Which gets the EDL by scanning the original TS/MPG files). All GBPVR needs to know is the time line of the MKV/AVI/TS,etc. I guess the key is getting that info from the PCH and then being able to send to command to skip to the next point. I'll PM you with my IP once I get the FTP server up.