Occasionally get SAP audio feed from CBS

[philly_phenom]

I got a message from another user asking for more information on my resolution, & since I thought maybe others might have the same issue, I should post the answer here.

First, I needed to determine which audio feed was the feed I wanted for a particular station. To do so, I opened a video file in VideoRedo (in my case NCIS - since that was a program that gave me trouble) & the selected Tools->Select Stream.

Choose an audio stream & hit play. If it plays back w/ SAP, then you know you picked the wrong one. Select the other audio stream & note the PID.

Please note that the PID's are in hex format in VRD - meaning that if the "good" stream's PID was x34, I need to make sure the Vprj file created by comskip has a value of 52 (the decimal equivalent) for the audio PID.

To ensure this, I created a batch file that I added to PostProcessing.bat that ran after comskip completed. (see attached) Select Audio uses "sed" to do a find & replace to provide the correct PID for a given channel.

In my case, I only applied it to channels that I ever had a problem with VRD choosing the wrong audio stream when cutting commercials.

Hope this helps anyone else out there.

[steveum]

I often see this same problem with comskip. It sometimes generates Vprj files with wrong audio stream pid. If I don't catch the problem, I always end up with a video with no audio.

I am curious how you corrected this in your batch processing.

I always use video redo manually and use the ctrl-L to inspect the audio stream. If it looks wrong, I close video redo then go edit the Vprj file to correct the pid. I can determine the correct pid by opening the recording directly with VideoRedo and then using the ctrl-L to find the pid.

Update: I see you posted your bat files. I will take a look at them.

[Anthony]

Thanks to the solution philly_phenom supplied, I came up with a somewhat simpler and more light weight solution.

I use the "Find And Replace Text" utility (FART) at:

http://sourceforge.net/projects/fart-it/

I save the fart utility (about 69K) in the same folder as my batch file, then add this one line to my batch file:

fart "%~dpn1.VPrj" "<AudioStreamPID>53" "<AudioStreamPID>52"

You could run FART additional times if you needed to substitute other audioPID's, but so far this is the only problem I have encountered.

Thanks for tracking down the cause philly_phenom!

[persim]

I have a pair of HVR-1600 tuners (over the air), as well as an HVR-2250 tuner (QAM cable), and my recordings occasionally end up with the SAP track also. I have had it occur with both CBS and PBS. Recordings on CBS are often out of sync also, whereas all other channels seem fine.

I have tried rescanning and remapping my HVR-1600, but there's no easy way to tell which channel is the one I'm supposed to select. For instance, my main PBS channel lists

10.1 OPB-HD (eng)

and

10.1 OPB-HD (eng(AC3))

Other than the name, GBPVR only shows an audio ID of 52 for the first example, and 53 for the second. All other fields are identical. I think one is in 5.1 audio, and the other is mono, but there's no way to tell other than making a recording and seeing what the result is.

In the case of the CBS channel, the only choices I have are the (eng) and the (spa) channels, and yet I sometimes get the SAP in my recordings.

I am currently using the TS Mux for recording, which my commercial processing later loads into VideoRedo for processing. It saves it as MPG, which MKVMerge then converts to MKV for better compatibility with my media player (TVIX M6500). Of course, this is all automated and I may not watch a show for a couple of weeks after it is recorded. By then, the original TS recording is long gone.

So, I can't help much, other than to confirm I have the same problems also...

Anthony

Have you tried changing the mapping selection? I have had the same problems with spanish recordings on certain broadcasts (Super Bowl) and traced it down to the mapping with (AC3) in it. Once I changed all my mappings to the one without the (AC3), everything was fine. Since I don't do any post editing for commercials I figured this might help you if you tried changing the mapping before anything else.

[Anthony]

persim,

Changing the channel mapping doesn't always solve the audio problems. For instance, in my area, CBS transmits both the standard audio track and a second SAP audio track in the one channel. Usually the SAP channel has the same audio as the main channel, but it is delayed slightly making everything out of sync. Other time the SAP channel has narration for blind viewers, which can be funny at times, but most of the time it's annoying.

For whatever reason, comskip seems to select the SAP channel instead of the main channel.

The fix philly_phenom recommended works great, as does my simplified alternative.

Anthony