MPEG-TS transcoding - MPEG2 compliance?

[DrLuny]

Hello all, I have a newbie question about MPEG TS transcoding, related to the MPEG2 compliance of MPEG TS files made with VLC media player. I use Windows XP and VLC media player 0.8.6 (also tried 0.9.6).

I have plenty of external hard disk for my DVB-T set top box (Maximum T-8000, same family as Marusys and Elanvision brands) but no DVD player at the moment. So, using VLC media player, I'm trying to transcode some home video AVI's and a couple of old store-bought DVD's to TS files that would play on my set top box. There is a small Windows application called mkrecord which can be used to add to the TS file the specific headers the box wants.

In VLC, "Stream and save" to a MPEG TS file works fine. I can select mp2v video and mpga audio (these are what the box uses in its TV recordings) and even DVB-S subtitles or all elementary streams. But the resulting TS file (with the headers made by mkrecord) does not work in my box. The file is being read by the box (the LED on the disk blinks away until "pause" or "stop" are pressed on the box remote, and continues to blink when "play" is pressed) but the screen remains black and there is no sound either.

Then I found and tried a $75 commercial software called VideoReDo TV Suite which has good transcoding capabilities including MPEG TS input and output, and a "QuickStream Fix" function that does make VLC media player's TS files work with my box. Here's the description of what it does:

"QuickStream Fix: This dialog is used to re-multiplex an MPEG2 program stream. It will copy the input file to the output file through the VideoReDo stream processing routines. This means that all the time stamps in the output file, such as PTS and GOP headers, will be re-calculated. In addition, all the processing parameters as specified on the Advanced Stream Dialog will be honored as well. In other words the output file will be MPEG2 compliant file.

The key purpose of QuickStream Fix is to re-align the time stamps in the output file. Sometimes, video captured from DVB Satellite or sourced from DVD VOB or VRO files may have internal time stamps that are not sequential. When you normally open a file in VideoReDo it will search for these non-sequential time stamps and handle them --gracefully. Occasionally it is unable to do so effectively and the QuickStream Fix function will prove useful."

Now my newbie interpretation is that the TS files produced by VLC media player (with default settings) are not strictly MPEG2 compliant, and that's why they don't work on my set top box. There may well be a combination of VLC media player options to use to achieve such compliance, but I haven't found it. So, if anyone knows the exact options to select in VLC media player transcoding to achieve the same result as with "QuickStream Fix" of VideoReDo TV Suite, please tell me too.

For us dummies, it would be very useful if VLC's "stream and save" transcoding dialogue had a check box like "force MPEG2 compliance" to make things as simple as possible. Come to think of it, I don't know why strict compliance would even be anything but the default...

Any constructive comments, hints and gentle derision much appreciated

[Jean-Baptiste Kempf]

Mail streaming@videolan.org for ideas.

[leicray]

Hi,

For what it's worth, I too am struggling with streaming to the Maximum T-8000 that I have for evaluation at the moment.

My experience overall seems similar to your's. I own a Topfield TF5800PVR and use VideoReDo TVSuite to edit recordings. Recordings from the Maximum T-8000 open and play fine in VideReDo TVSuite even though it's not specifically aware of the Maximum ts format. I have even used VideReDo TVSuite to convert old files saved from the Topfield in mpeg format to ts files which when run through mkrecord can be uploaded and played successfully on the Maximum T-8000. It took lots of Googling before I found out about the need for mkrecord which I managed to download from the Elanvision site. Why is it not included on the PVR manager CD that's bundled with the Maximum?

However, streaming has been a bit of a mystery so far. The lack of proper documentation has been the biggest barrier to progress and I'm probably not going to worry too much about it as I've managed to figure out the issues that I see as important for me: getting programs out of and back onto the PVR.

I'm also been rather dissappointed that there is no Maximum T-8000 community providing support in the way that there is for the Topfield (http://www.toppy.org.uk/).

Anyway, treat this message as moral support, rather than useful suggestions.

[DrLuny]

As I recall, VLC streaming to the T-8000 worked pretty easily - once the Ethernet connection between the box and my PC was up, I just used Maximum´s PVRmanager 2.0 mfserver application to define the appropriate folder on my PC to the box. After that, this folder was visible in the Multimedia/VLC streaming menu of the box, and pressing "OK" on the remote for any multimedia file in that folder made VLC start on the PC and the file was streamed to the box just fine.

There was some compatibility issue though, this worked with VLC 0.8.6 versions but no longer with the 0.9 versions as the command line syntax of VLC was changed. I don't know if there is a newer version of PVRmanager 2.0 or a patch to fix this - if not, downgrading to VLC 0.8.6 helps.

[leicray]

I downgraded to VLC 0.8.6 and that indeed worked. I'm using the most up to date version of PVR Manager (2.0.0.2) so the issue of the command line syntax having been changed still need to be addressed by Maximum.

Thanks for the guidance.