rescan fouled up some channels

[johnsonx42]

I re-scanned today to fix one channel that had changed (KDOCDT), and found after the rescan 5 other channels were broken. KCOPDT, KNBCDT KABCDT, KCETDT2 and KLCSDT2 all had lost audio or video, even though I didn't change those mappings. I presume this is the new functionality mentioned in the release notes to automatically 'fix' channels whose program stream id's had changed.... in my case it only broke them!

I was able to manually fix the tuning requests (with some knowledge and a little help from TSReader Lite), as follows:

no video: T:13,0,0~P:3~TSID:301~V:2547~A:52~PMT:48~PCR:49~N:>13.1 KCOP DT (000)
correct: T:13,0,0~P:3~TSID:301~V:49~A:52~PMT:48~PCR:49~N:>13.1 KCOP DT (000)

no audio: T:36,0,0~P:3~TSID:291~V:49~A:53~PMT:48~PCR:49~N:>4.1 NBC-4LA (000(AC3))
correct: T:36,0,0~P:3~TSID:291~V:49~A:52~PMT:48~PCR:49~N:>4.1 NBC-4LA (000(AC3))

no video: T:7,0,0~P:1~TSID:295~V:986~A:52~PMT:48~PCR:49~N:>7.1 KABC-DT (eng)
correct: T:7,0,0~P:1~TSID:295~V:49~A:52~PMT:48~PCR:49~N:>7.1 KABC-DT (eng)

no audio: T:28,0,0~P:2~TSID:305~V:97~A:101~PMT:96~PCR:97~N:>28.2 KCET-OC (000(AC3))
correct: T:28,0,0~P:2~TSID:305~V:97~A:100~PMT:96~PCR:97~N:>28.2 KCET-OC (000(AC3))

no video: T:41,0,0~P:3~TSID:309~V:2304~A:68~PMT:64~PCR:65~N:>58.2 KLCS-DT (000(AC3))
correct: T:41,0,0~P:3~TSID:309~V:65~A:68~PMT:64~PCR:65~N:>58.2 KLCS-DT (000(AC3))

Yes, it did the same across both of my tuners (per my sig), so it's not a tuner or driver issue.

So, something is broken in the ATSC scanning logic in this release (I've scanned numerous times in every release from 1.2.13 on, and never had it get any of the PID's wrong before). Second, perhaps automatically updating the existing tuning requests should be optional rather than automatic. I shudder to imagine if it had borked all of my tuning requests, I'd have been hand-entering tuning requests all day long.

As an aside, I also initially tried doing a manual scan on just the one frequency I wanted to update, but found the scanner would just find the same channel over and over and over again until I stopped it. I tried it on a couple of different frequencies, and it would do the same thing. So I did a full rescan.

I'm afraid I don't have the config and config-native logs from the original channel scan any longer - I've been in and out of config so many times fixing the channels that those logs are long gone. I can re-scan again some other time and get logs if it would help.

[sub]

I'm afraid I don't have the config and config-native logs from the original channel scan any longer - I've been in and out of config so many times fixing the channels that those logs are long gone. I can re-scan again some other time and get logs if it would help.

Bugger. If you get a chance to reproduce this and post the logs, it'd be very helpful.

[johnsonx42]

ok, I'll do another scan tonight or tomorrow... I have to make sure I have plenty of time with no important recordings coming up, since I'll likely have to fix some tuning requests (I guess this is a case where having only 20-odd channels is a blessing). It will be interesting to see if it fouls up the same channels the next time - I presume it will, since it did the same across two different tuners the first time.

Anything else I should do diagnostically when I do the scan?

[sub]

Anything else I should do diagnostically when I do the scan?

Might be worth zipping up a backup of your gbpvr.db3 and scan config files beforehand, so I can compare the results with your logs.

[johnsonx42]

Thy will be done, in California as it is in Wellington.

[Graham]

I suspect that if you press Cancel and not OK to get out of config.exe, you won't update the database and will keep the channel settings that you had before you started config.

I expect that the logs will still show what happened during any scan that you do in config.

[johnsonx42]

Hey, sub, I know you're away from home, but check this out:

This fellow here: http://forums.nextpvr.com/showthread.php?t=43637 lives in my corner of California, and gets the exact same stations I do. He also got the exact same incorrect PID's that I did. Unlike me though, he's got a log of it (yes, sorry, I was supposed to re-scan and get you a log, but I just never got around to it). His config.exe-3 and config.exe-native-3 logs show his channel scan; you can see where it gets the wrong PIDs.

When you get back, let me know if you want a Full-TS recording of the problem frequencies.

[eramos581]

I re-scanned today to fix one channel that had changed (KDOCDT), and found after the rescan 5 other channels were broken. KCOPDT, KNBCDT KABCDT, KCETDT2 and KLCSDT2 all had lost audio or video, even though I didn't change those mappings. I presume this is the new functionality mentioned in the release notes to automatically 'fix' channels whose program stream id's had changed.... in my case it only broke them!

I was able to manually fix the tuning requests (with some knowledge and a little help from TSReader Lite), as follows:

no video: T:13,0,0~P:3~TSID:301~V:2547~A:52~PMT:48~PCR:49~N:>13.1 KCOP DT (000)
correct: T:13,0,0~P:3~TSID:301~V:49~A:52~PMT:48~PCR:49~N:>13.1 KCOP DT (000) etc.

Where can I get the documentation that describes what all these ('V" and "A" and "PMT" and "PCR" values mean?
Thank you in advance.

[dennit]

Where can I get the documentation that describes what all these ('V" and "A" and "PMT" and "PCR" values mean?
Thank you in advance.

The format of the string is GBPVR-specific, but the content is relatively straight forward. First, there is info for selecting a frequency to tune, then info for selecting the transport stream on that frequency that has the channel you want to view/record, and finally a name for the channel. It sounds like you want to know about the transport stream parameters. You can start with Wikipedia's description of TS.

[johnsonx42]

The V: and A: are the desired Video and Audio stream ID's. I don't know about the PMT and PCR values, but they've always been correct. http://en.wikipedia.org/wiki/MPEG_transport_stream
You can use TSReader Lite to examine your channels and see what the correct values are.