What is a PCR rollover ? (1 Viewer)

[level20peon]

I occasionally am experiencing a "PCR rollover" when watching TV. When this happens the playback doesn't remain fluid.

21-12-2007 19:58:44 PCR rollover detected
21-12-2007 19:58:44 PCR: 0 days 00:28:07 236 new: 0 days 00:00:00 22 prev: 1 days 02:30:43 703 start: 0 days 00:00:00 0 diff: 1 days 02:30:43 680 hole: 0 days 00:00:00 0 holeB: 0 days 00:00:00 0  - pid:20b

What is the meaning of this ?


-level20peon

 

[Paranoid Delusion]

I just googled the technical answer, heavy reading, phew.

From what i can gather it is a misread on a video transmission on its timeframe, hence the skipping.

So when the frames do not go in there logical time order, it spits out this error.

Would not think its a transmission error, more like a read one.

That's the impression i got from the article, correct me if i got this wrong anyone.

 

[Emerica]

Sorry to bring up an old post. Found this thread in google and maybe the answer above is a little misleading.

The PCR is a program clock reference.

To simplify this a bit:
Transport streams have a main clock, the PCR. This number is a 32bit value, a time stamp essentially.
Each element in the stream generally has timing as well, PTS/DTS Presentation and Decode Timestamps.
This is how the streams can maintain sync with each other working off the Master PCR clock.

You only have 33/32 bits to store the PCR, So you can only have this number get so big before it overflows and needs to be reset back to 0. This is what the rollover is. Once the clock gets to that time is has to get reset to 0 because it can't get any higher.

I'm guessing that glitch in the stream is the decoder having a problem with that jump from 28:h to 0h, it probably loses sync and has to reacquire the stream again.

Rollover = Reference Clock Reset