GraphRecorder - Full program not recorded

[mikeh49]

I'm using Graphrecorder to capture from firewire on my STB. Recently I have had a problem with some entire programs not being recorded - perhaps 5 mins of a 1 hour program. This seems to be concentrated on a channel that has a malformed TS stream.

Attached is the recording service log from an attempt to record Medium at 2200 on 2/16/09. This was a back-to-back recording following a program on the analog capture source. Also, I'm running contig and comskip in postprocessing.bat file and have comskip set to play nicely and run at low priority.

This problem may have started after I installed the 1/26/09 graphrecorder dll?

Any thoughts?

[carpeVideo]

I see a couple of things - it seems to have an issue starting (two tries where the filesize stays at 0) but it does get started. The stop command for the graph is not given until 1 hour later which is correct. My guess is the channel is on a high frequency that has a spotty connection and the malformed TS stream is killing the transcode you are doing in the graph. Is it repeatable on this channel and not others? If so isolate your antenna connection to your cable box (no other STBs / cable modem) make sure all connections are tight and see if it improves, that will tell you if its a signal strength issue with your cable and STB.



2009-02-16 21:59:28.953 VERBOSE [5] GraphRecorder[11429296]tartProgram: Performing filesize check
2009-02-16 21:59:28.953 VERBOSE [5] Graph Recorder: checking if G:\Recordings\Medium\Medium_20090216_22002300.mpg is growing.
2009-02-16 21:59:28.953 VERBOSE [5] Filesize = 0
2009-02-16 21:59:29.343 VERBOSE [5] Filesize = 14336
2009-02-16 21:59:29.546 VERBOSE [5] Filesize = 24576
2009-02-16 21:59:29.750 VERBOSE [5] Filesize = 38912


2009-02-16 23:02:00.015 VERBOSE [5] Recording has passed endtime+padding. Stopping.
2009-02-16 23:02:00.015 VERBOSE [5] GraphRecorder[11429296]: enter stopRecording()

There is also the odd possibility that the 5C broadcast flag is set and the STB is not giving an unencrypted stream for that program, I have heard others mention they have seen this issue.

Another way to check is to set up a preview graph and hit preview in graphEdit and change the channel to this station during one of the programs.

CV

[mikeh49]

I'll do some more investigating and post back. The cable guy replaced all the at the set cables with his cable and cableco high quality connectors and he was satisfied. But, I'll check some more; I think the cable box has some signal level indications.

[mikeh49]

Did some investigation using the Motorola DCT64xx cable box diagnostics. The results:

Problem Channel 782: 783 Mhz, 28.8 dB SNR, poor, 600 or more correctable errors in 5 sec

Channel 792: 657 Mhz, 36.8 dB, good, no errors

Channel 780: 813 Mhz, 35.9 dB, good, no errors

Other channels in the 600 MHz range are all similarly good.

So, it looks like a signal strength issue, but perhaps not just related to frequency since a higher frequency channel is good. Maybe there is a notch filter someplace? The cable box handles this just fine, i.e. I can't tell the difference on the TV, and the preview graph in Graphrecorder works fine. Preview uses the MS MPEG demux to feed the decoders, IIRC. I know the Nvidia transport demux works also. In previous testing (a month ago) Sub's TS reader was able to play this stream.

I'll try some cable changes next and do a little more research.

Then again, maybe its related to the digital transition; the problem channel (KHQ in Spokane) turned off the analog last Tuesday. But then so did 780 (KXLY in Spokane).

[carpeVideo]

Thanks for the update - can you post i instructions or a link on how to use the moto stb diagnostics?

[mikeh49]

Here's the link to the Moto STB diagnostics (and other stuff):

http://replayguide.sourceforge.net/dct6412/

Key section edited and pasted below:

Code:

NOTE: You will only be able to capture channels/recordings without 5C protection enabled. To check for 5C protection on channels that you are interested in capturing from (or have recorded from), do the following:

    * Start with DCT64xx turned on.
    * Tune to a channel you are interested in recording from.
    * Enter DIAGNOSTICS page on the DCT64xx as follows with remote: Press Cable, Power off, Select, Select. [B]Comment: I think you just need one Select here, and the keypresses have to be in fairly rapid sequence.[/B]
    * Scroll down to: d11 INTERFACE STATUS and then click right arrow to enter that module.
    * In 1394 I/O DEVICE section you should see ACTIVE PORTS=1 (indicating the Firewire connection is active) and look at 5C IMPLEMENTATION value. If it is something other than 0 this means 5C protection is enabled and you won't be able to capture that channel.
    * To get out of the Status Page click left arrow with remote and scroll down to EXIT and click Select.

The channel status is on the Inband Status page (d04, IIRC) - frequency, SNR, errors, etc.

Lots of other stuff to look at also.