AMIKO No audio on NBC

spongella

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May 12, 2012
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Know I asked this question previously, can't find the answer using Search, so here it is. 99W C has no audio (says Dolby), I think Michael said something about an update, which would that be? And would that update include any other recent updates needed for the Amiko Mini HD SE? Am trying to get a handle on these on-line updates thanks.
 
Hit the red button on your remote, to bring up a list of alt audio PIDS and select one.
 
What I've been experiencing on a lot of the NBC channels is that they have a 5.1 feed split up into pairs, but no straight stereo feed. So I can either select left and right which doesn't contain dialogue, or I can get the center channel which has dialogue in mono but doesn't always have music or sound effects. Not quite optimal.
 
Not as simple as receiving all APIDs at once. NBC uses Dolby E which must be decoded and synchronized to produce all audio tracks.

The least expensive used Dolbe E decoder that I have seen has been about $1000. :(
 
On an X2 if you press the Audio button then select stereo then down arrow and select the third option (I believe it's AAE) the sound will come in. Can't speak for other STBs but see if you have options under the Audio button.
 
Not as simple as receiving all APIDs at once. NBC uses Dolby E which must be decoded and synchronized to produce all audio tracks.

The least expensive used Dolbe E decoder that I have seen has been about $1000. :(
I could do it for well under $1000 with 6 receivers, each tuned to a different APID. Hook 'em all up, each connected to a different speaker and 6 channel audio would fill my room! LOL
 
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If you can stream the signal through a computer there may be a way to use ffmpeg to process it in nearly real time. I remember reading some guy's blog post a while back where, if I recall correctly, he was recording signals and then using ffmpeg to convert the audio only to a Dolby format that would play in full 5.1 audio through his receiver. I think he had set it up so that ffmpeg ran as a post-processing command in TVHeadEnd, so the entire show had to be recorded before the conversion could take place, but I have heard that ffmpeg can be used on real-time streams so I've always wondered if it would be possible to do something like that in real time. Don't remember where I saw that now, and it probably wouldn't work anyway in a receiver that can't run ffmpeg, but if the receiver is running Linux internally then it might be possible for the manufacturer or US distributor to add ffmpeg and a way to do this conversion, either on recordings or in real time, if they had any interest in doing such a thing.

If anyone is seriously interested in this and a Google search doesn't locate the page for you, I might be able to find it again, but it would probably take me a while. If I recall correctly it wasn't that complicated, he was just calling ffmpeg and passing the video and data streams unchanged, and mapping the audio to Dolby 5.1 (but only on recordings, not in real time). I also seem to recall that the audio layout was similar to that used on other feeds (like you sometimes see on the slates on the feeds channels) except divided up among three APIDS, so the three APIDS had the channels like this: (Left Front, Right Front) (Center, Low Frequency Emitter) (Left Surround, Right Surround).
 
ancient, was it this command to post-process a .ts file?

ffmpeg -i "original program filename.ts" -c:v copy -filter_complex '[0:1][0:2][0:3]amerge=inputs=3,pan=5.1|FL=c0|FR=c1|FC=c2|LFE=c3|BL=c4|BR=c5' -c:a mp2 "converted program filename.ts"

Here is the link that you may have been referring to: https://freetoairamerica.wordpress....-certain-network-which-shall-remain-nameless/

The above should work for pre-recorded .ts files. It might also be possible to do it in real time with a pipe buffer.
 
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The least expensive used Dolbe E decoder that I have seen has been about $1000.
Plenty of units on ebay for under $200, a few go for under $100.
That would get you 2 channels via a headphone track.
For full audio sound, you would also need a Dolby DP569 - "reasonably" priced on ebay too.

However, I don't think NBC uses DolbyE.
DolbyE uses just one audio pid with serveral tracks, where NBC is using different audio pids for each track.

DolbyE is not a "cheap" option, but a neat learning experience.
 
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Thank you Lak7, I stand corrected on the Dolby E being present on all broadcasts. It appears to be used on select programming.

The primary distribution mix is 5.1 and this is the typical primetime assignment:
1 - Left
2 - Right
3 - Center
4 - LFE - Effects
5 - Surround - Left
6 - Surround - Right
7 - Descriptive / SAP - Left
8 - Descriptive / SAP - Right

Many shows have a stereo mix on 1 or 2. I have noted that additional audio tracks are often used for special event feeds such as sports or award shows. Dolby E often is on 4.

Production discrete audio that was defined in this 2008 NBC Universal HDTV document. 12 discrete audio tracks are not available on STBs and I often need to look at the tables (using TSReader) to see what APIDs are present. VLC allows the user to select the single or combination of APIDs to be played. As the programming sources seem to use the tracks differently, the selection of the left/right center tracks vary between several APIDs.
-------------
2.0) AUDIO: 5.1 CHANNEL SOUNDTRACKS:
• The following audio formats apply:
Provide a 5.1 channel discrete soundtrack.
The following channel order shall apply:
• Ch 1 = Left
• Ch 2 = Right
• Ch 3 = Center
• Ch 4 = LFE
• Ch 5 = LS
• Ch 6 = RS
• Ch 7 = Second Audio Program (SAP) (if applicable or silence)
• Ch 8 = Video Descriptive Service (VDS) (if applicable or silence)
• Ch 9 = LT (Pro Logic-II or Pro Logic) or LO or stereo
• Ch 10 = RT (PL-II or PL) RO or stereo
• Ch 11 = left music/effects (if applicable or silence)
• Ch 12 = right music/effects (if applicable or silence)
Please Note:
• Content providers have no restrictions concerning the placement of common audio across multiple channels. Prior limitations and restrictions are no longer in effect.
• Program and commercial content providers are encouraged to mix and supply discrete 5.1 channel soundtracks when available in lieu of matrix encoded LT RT 2-channel soundtracks. Until further notice, NBC’s audio distribution system reproduces LT RT soundtracks on the front left, front right channels only of 5.1 consumer home theaters. Consumer stereo and mono reproduction operates with any soundtrack format.
• Center channel (C) dialogue intelligibility is extremely important and is to be established and maintained for the duration of the content
• Use of a low frequency enhancement channel (LFE) is encouraged when deemed appropriate by the sound designer. Some portion of the 4 LFE signal is to be mixed into the left and right channels to maintain the appropriate presence of this signal for 5.1 to two channel down mixing for non 5.1 audience playback systems.
• NBC requires specific peak limiting of –8 dBFS for all audio soundtracks. HDTV programming is frequently downconverted for use on the NBCU SD Television Network and must be peak limited until termination of the NTSC system.
.
2.2) 5.1 CHANNEL SOUNDTRACKS MUST BE ACCOMPANIED BY A 2- CHANNEL VERSION: For 5.1 channel soundtracks as above, the following additional audio formats apply in this order of NBC preference:
• VTR PCM Audio tracks 9 and 10 must contain one of the following:
• 2 channel PCM/AES Dolby Pro Logic II matrix encoded soundtrack
• 2 channel PCM/AES Dolby Pro Logic matrix encoded soundtrack
• 2 channel stereo soundtrack
• 2 channel dual mono soundtrack
• The soundtrack shall be dynamically limited not to exceed – 8dBFS
Recording of one of the above PCM soundtracks on channels 9 and 10 MUST BE in addition to the 5.1 soundtrack recorded on channels 1-6 of the HDCAM-SR tape.
All audio tracks shall be time-aligned to video (+/- 1 millisecond) at the audio and video outputs of the playback VTR.
2.3) 2-CHANNEL ONLY SOUNDTRACKS. If a 5.1 soundtrack is not provided, the following audio formats apply in this order of NBC preference:
1. Provide a 2 channel PCM/AES Dolby Pro Logic II matrix encoded soundtrack (stereo compatible) on PCM Ch 1 and 2
2. Provide a 2 channel PCM/AES Dolby Pro Logic matrix encoded soundtrack on PCM Ch 1 and 2
3. Provide a stereo soundtrack on PCM Ch 1 and 2
4. Provide a dual mono soundtrack on PCM Ch 1 and 2
5. For mono audio content, the same audio material shall appear in phase and of equal level on PCM Ch 1 and 2
Please Note: In all cases for 2-channel soundtracks as above tracks 3 thru 6 must be silent as follows:
• Ch 1 = LT (left if stereo)
• Ch 2 = RT (right if stereo)
• Ch 3 = silent
• Ch 4 = silent
• Ch 5 = silent
• Ch 6 = silent
• Ch 7 = Second Audio Program (SAP) (if applicable or silence)
• Ch 8 = Video Descriptive Service (VDS) (if applicable or silence)
• Ch 9 = LT (Pro Logic-II or Pro Logic) or LO or stereo
• Ch 10 = RT (PL-II or PL) RO or stereo
• Ch 11 = left music/effects (if applicable or silence)
• Ch 12 = right music/effects (if applicable or silence)
Provide SAP and/or VDS if applicable on channel 7 and 8 respectively or silence if no SAP or VDS on the unused track or tracks
Provide repeat of tracks 1-2 on tracks 9/10,
The soundtrack shall be dynamically limited not to exceed –8dBFS
Provide M/E on tracks 11/12 if applicable or silence if no M/E
2.4) ADDITIONAL AUDIO INFORMATION
• NBC HD content will be accepted using PCM/AES matrix surround (PL-II, PL), stereo or mono audio conforming to SMPTE EG26 and related documents.
• All audio tracks shall be time-aligned to video (+/- 1 millisecond) at the audio and video outputs of the playback VTR.
• Content will not be accepted with Dolby E or Dolby Digital soundtracks
• Content will not be accepted using separate video and synchronized audiotapes. (Double System).
• No audio encoding format is to be used that is not specified in this document
2.5) GENERAL AUDIO SPECIFICATIONS
• PCM/AES Audio
NBC reference level is –20 dBFS. (This is as it corresponds to –20 dBFS = +4 dBu analog. 0
dBFS = +24 dBu analog. (ref: SMPTE RP-155). All 0 vu analog references pertain to +4 dBu
and –20 dBFS if a corresponding digital scale is used.)
• Digital audio format shall be: AES-3, 48kHz sampling, 24 bit resolution
• NBC requires specific peak limiting of –8 dBFS for all audio soundtracks. HDTV programming is frequently downconverted for use on the NBCU SD Television Network and must be peak limited until termination of the NTSC system. Maintain peak limiting of –8 dBFS until further notice. The delivered mix and the DTV metadata transmitted with the content will determine control of dynamics for DTV. (See metadata table on page 7).
• All audio tracks shall be time-aligned to video (+/- 1 millisecond) at the audio and video outputs of the playback VTR.
2.6) AUDIO METADATA FOR SOUNDTRACKS - OPTIONAL: Though currently optional, NBC Universal is encouraging all content providers to start this encoding and delivery process as soon as possible in order to become familiar with this forthcoming requirement. NBCU will alert providers well in advance as to when this data can be transmitted and active).
• Audio metadata may be optionally encoded into the VANC of the content delivered to NBC to carry show specific data
• Process to conform to forthcoming SMPTE 2020-3
• Data must be encoded into VANC line 10
• DID = 0x45
• SID = 0x01
6
• DC = Variable
• Actual mixed average dialog level must still conform to the NBC standard of –23 LKFS until further notice (see 2.6 above)
• When active, all metadata parameters will be transmitted on the NBC Universal DTV network exactly as delivered. Please make certain that each parameter is set to exactly match your content.
Proper formatting is crucial for setting 5.1 or 2/0 channel play out for air. Metadata dialog level will set the program loudness and line and RF modes will control dynamic range, Surround mixdown parameters will be controlled by this metadata as well.
• PLEASE ENSURE THAT THE DUBS OF YOUR MASTER DELIVERED TO NBCU HAVE VALID AND CONTINUOUS DATA ON VANC LINE 10
• Tapes not containing valid audio metadata on VANC line 10 will default to the NBC Universal audio metadata standard specified on page 7 of this document

----

Be interesting to view to entire document and more recent versions.
 
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Guess where my screen name came from partially?
fm.jpg


I used to have a favorite chip when I was a kid, thanks to Forrest Mims.
 
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I know what you mean. I built a lot of different projects of the trusty ole 555. :)
 
ancient, was it this command to post-process a .ts file?

ffmpeg -i "original program filename.ts" -c:v copy -filter_complex '[0:1][0:2][0:3]amerge=inputs=3,pan=5.1|FL=c0|FR=c1|FC=c2|LFE=c3|BL=c4|BR=c5' -c:a mp2 "converted program filename.ts"

Here is the link that you may have been referring to: https://freetoairamerica.wordpress....-certain-network-which-shall-remain-nameless/

The above should work for pre-recorded .ts files. It might also be possible to do it in real time with a pipe buffer.

Yes, that was it, although that article shows the output format as eac3, not mp2, but anyway thanks for finding that! By the way, if it's possible to do it in real time using TVHeadEnd I'd really like to know how, but I'm not at all familiar with the concept of a pipe buffer or how you'd set one up in TVHeadEnd. But if we discuss that, we should probably start a new discussion in the general FTA forum, since AFAIK none of the available FTA receivers run TVHeadEnd.
 
Curious if this is why the newer receivers I have bought do not have any audio on dolby. Its the cheap no no name receivers from China. Do you guys think if I got a dolby digital to analog output it would work? I would hook it up from the digital audio coax (RCA) port into the box that breaks them out analog
 
The cheap boxes are not paying the Dolby Licensing fee, so they are not decoding it.
 
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