WTBS HD and AC3 Filter - No sound (anlog output)

[svemuri]

Hello all,
I am using the latest released version of Sage 4 to create a HD PVR. It works fine with Nvidia Purevideo and SP/DIF. However, I wanted to use analog outputs of my sound card (trying to downmix to 2 channel so the output can be fed to a RF modulator for wholehouse distribution). I have the bronze version of Purevideo, so I know it won't decode AC3. So I am trying AC3 Filter 1.2b8. It mostly works, except for the WTBS station. There is no sound at all.

I fiddle around with TSReader Lite. It appears as though all other stations are broadcasting AC3 2 channel. WTBS is the only one with Two audio streams, one 5 channel and another 1 channel. I am trying to figure out whether this is a AC3 filter problem or Sage incorrectly selecting the 1 channel audio stream. Any insight is much appreciated.

Thanks
Sarat.


Here is the TS Reader output if you are interested:

Channel 3
Service Name: WTBS-HD
TSID: 745 (0x02e9) NTSC: 17 ATSC: 20 GA ATLANTA
Channel Number: 17.1
Carrier Frequency: 0
Modulation Mode: ATSC (8 VSB)
Source ID: 3
Extended Channel Name: WTBS-HD
Service Location Descriptor:
 PCR PID 0x0031
 Stream Type 0x02 (MPEG-2 Video) ESPID = 0x0031 Language = eng
 Stream Type 0x81 (AC-3 Audio) ESPID = 0x0034 Language = eng
 Stream Type 0x81 (AC-3 Audio) ESPID = 0x0035 Language = eng

Elementary Stream PID 49 (0x0031) MPEG-2 Video
MPEG Video: Bitrate 45.000 Mbps Resolution 1920 x 1080i
MPEG Video: Framerate 29.97 fps Aspect Ratio 16:9 Chroma Format 4:2:0

Descriptor: Data Stream Alignment Descriptor
Alignment type: video access unit

Descriptor: ATSC Caption Service Descriptor
 e1 65 6e 67 c1 3f ff                             .eng.?.

Elementary Stream PID 52 (0x0034) AC-3 Audio
AC3: Bitrate 448 Kbps Sample Rate 48 KHz
AC3: Mode complete main Coding 3/2 5 L, C, R, SL, SR

Descriptor: Registration Descriptor
 Format identifier: 0x41432d33 (AC-3)

Descriptor: ISO639 Language Descriptor
 Language: eng
 Audio type: undefined

Descriptor: ATSC AC-3 audio Descriptor
 08 be 1b 09 1f                                   .....

Elementary Stream PID 53 (0x0035) AC-3 Audio
AC3: Bitrate 192 Kbps Sample Rate 48 KHz
AC3: Mode complete main Coding 1/0 C

Descriptor: Registration Descriptor
 Format identifier: 0x41432d33 (AC-3)

Descriptor: ISO639 Language Descriptor
 Language: spa
 Audio type: undefined

Descriptor: ATSC AC-3 audio Descriptor
 08 a9 03 0a 1f                                   .....

[svemuri]

Problem appears to be solved. Used FFDSHOW audio decoder which displays the input stream. It showed that on WTBS, input is a AC3 single channel, which lead me to believe that Sage is picking the wrong audio stream. So, I deleted all the video sources and re-added them. That seem to do the trick. Now, WTBS comes in AC3 6 channels.

Hopefully, this will help other people with similar problems.

Sarat.

[Polypro]

Good post, thanks.

P

[svemuri]

Well, that was a short lived success. This morning WTBS was without sound again. I guess EPG download somehow messes up the PIDs and Sage selects wrong stream.

I am running 4.1.3 version of Sage. I guess I am going to install the latest Beta and see what happens

On a positive note, I discovered FFDSHOW in this ordeal. Previously Nvidia Purevideo + AC3 Filter was crashing on DVDs. However Purevideo + FFDSHOW Audio decoder seems to work ok.

Sarat

[Robsters]

I'm experiencing the same problem. Started very recently on our local WB (Los Angeles, CA aka Channel 5). All other channels play audio in DD5.1 just fine.

Video plays fine... but no audio. I'm using AC3filter to output via SPDIF. I don't get any analog audio from these recordings either when I try different audio decoders.

I'm able to convert my .TS files into xVid AVIs and play them with the audio just fine!

I haven't lost a recording yet, but its very annoying to spend 20 minutes every time I want to watch an hour show recorded from WB-DT.

I've noticed that all the files I've had to convert had TWO audio channels and I can pick the alternate channel but don't when converting.

I believe my problem is with Sage and the inability to pick the audio stream to playback.

Robert

[svemuri]

It does sound like that same problem.

I upgraded to the latest beta (4.1.13?) and so far it resolved the audio problem. I suggest that you try the latest beta as well.

Also, I like FFDShow audio filter better than the AC3, especially since it plays nice with nvidia decoders for DVDs.

Sarat

Originally Posted by Robsters

I'm experiencing the same problem. Started very recently on our local WB (Los Angeles, CA aka Channel 5). All other channels play audio in DD5.1 just fine.

Video plays fine... but no audio. I'm using AC3filter to output via SPDIF. I don't get any analog audio from these recordings either when I try different audio decoders.

I'm able to convert my .TS files into xVid AVIs and play them with the audio just fine!

I haven't lost a recording yet, but its very annoying to spend 20 minutes every time I want to watch an hour show recorded from WB-DT.

I've noticed that all the files I've had to convert had TWO audio channels and I can pick the alternate channel but don't when converting.

I believe my problem is with Sage and the inability to pick the audio stream to playback.

Robert

[Robsters]

Thanks!

I'll give that a try.