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MPEG2 Transport Stream w/ PCM Audio <-?!?!?->

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Michael McIntyre
MPEG2 Transport Stream w/ PCM Audio <-?!?!?->
on May 1, 2012 at 6:40:22 am

New request from an ongoing client (satellite broadcast outlet). Up to now, all HD deliveries have been HDCAM. Recently got asked for digital delivery:

HD MPEG2 transport streams w/ PCM audio
(rest of the specs don't matter here)

Sounds easy enough - it is not. I understand Fox has asked for these before as well as some European vendors. I know it can be done. Somehow.

Short of heavy-duty hardware {Tektronix, Snell & Wilcox, Tandberg maybe}, you'd think this would be a software slam-dunk.

Telestream Episode 6.2.1 notes that, "Not all container formats support all forms of PCM encoding. The selected encoding may be quietly converted into another encoding supported by the selected output format." Quietly converted means selecting MPEG-ts limits audio selections - PCM is not among them. Their GXF preset does wrap MEPG2 and PCM but outputs elementary not transport streams. Trying to pass-through PCM audio within the ts container yields failed encodes w/ "No importer found".

Sorensen Squeeze 8.1 Pro
offers "MPEG-PCM" as an audio option within MPEG2 transport streams but whatever they're wrapping together is not passing QC. PCM is obviously available in Squeeze within other codecs. Squeeze seriously wants to hand-hold users through format constraints.

Adobe Media Encoder 5.5.1 offers either MPEG2 Layer I, MPEG Layer II or Dolby AC3 when multiplexing to TS.

A rather silly (and hopefully unnecessary) workaround might be muxing together separate video / audio streams after encoding.

ffmpegX wants to convert the PCM to anything but PCM.

I've even run LEADTOOLS SDK trying to merge streams in their MPEG Encoder 3. Alas - I'm not a programmer or code whiz. Those development tools are DEEP. Probably ideal if you need to stream something from your unmanned UAV drone.


So - it'd be nice to hear from someone who's actually delivered this specific file format.

I know, I know - it's an odd recipe. Let's not play the "They should be delivering ______" game.

I'm trying to identify a very mission-specific software solution to these requested delivery specs. I'm actually enjoying the challenge of figuring it out.


Thanks in advance - Michael


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Craig Seeman
Re: MPEG2 Transport Stream w/ PCM Audio <-?!?!?->
on May 1, 2012 at 12:14:33 pm

[Michael McIntyre] "Telestream Episode 6.2.1 notes that, "Not all container formats support all forms of PCM encoding. The selected encoding may be quietly converted into another encoding supported by the selected output format." Quietly converted means selecting MPEG-ts limits audio selections - PCM is not among them. Their GXF preset does wrap MEPG2 and PCM but outputs elementary not transport streams. Trying to pass-through PCM audio within the ts container yields failed encodes w/ "No importer found". "

Try using AES audio and see if that passes their specs.



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Michael McIntyre
Re: MPEG2 Transport Stream w/ PCM Audio <-?!?!?->
on May 1, 2012 at 3:58:46 pm

Hey Craig,

Thanks for the input! I'll ask about AES. I do know AC3's definitely OUT and that they haven't tested AAC yet. I wonder who would win that audio cage-fight (AES, AAC, MPEG Layer II).

Manzanita Systems emailed this morning, "Hello Michael, The PCM insertion is starting to become more popular driven by Netflix. We will have a demo for you in a about a month. Please check back with us then. - Manzanita Sales"

So - of course I had to confirm the Netflix specs. 80 Mbps does seem like overkill. I assume they're dumbing it down pretty harshly for rollout through their automation. Netflix actually has MPEG-2 over PCM in their 'order of preference'.

Below are the specifications which are acceptable.
High Definition – MPEG-2 (80 Mbps)
1. Video Codec: MPEG-2
2. Profile ID: High Profile
3. Level ID: High Level
4. Video Bit-rate: 80 megabits
5. Resolution: a. 1280x720 b. 1920x1080

Audio Codec
File Type(in order of preference)
1. High Definition - MPEG-2 (80 Mbps)
2. Standard Definition – MPEG-2 (50 Mbps)
3. High Definition – Apple ProRes 422 HQ w/ uncompressed PCM audio only
4. Standard Definition – Apple ProRes 422 HQ w/ uncompressed PCM audio only


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Craig Seeman
Re: MPEG2 Transport Stream w/ PCM Audio <-?!?!?->
on May 1, 2012 at 4:06:46 pm

I believe there have been others who have been given PCM audio spec and found AES worked. It's uncompressed audio basically. It might be best to send them the file to test. This will avoid any assumptions.



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Michael McIntyre
Re: MPEG2 Transport Stream w/ PCM Audio <-?!?!?->
on May 1, 2012 at 5:13:25 pm

Thanks, Craig.

My latest feedback was that some PCM insertion was causing slippage with closed-captioning using a particular provider's workaround and they went w/ MLII instead. I guess I'll leave that debate to the audiophiles as I don't have a strong preference (AES vs. MPEG Layer II).

Again - the input is appreciated.


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Michael McIntyre
Re: MPEG2 Transport Stream w/ PCM Audio <-?!?!?->
on May 3, 2012 at 3:47:18 pm

Not bumping the thread or 'case closed' but what the players had to say through direct email and on support forums:

Telestream Episode (by far the most responsive and helpful team)
Episode 5 used Dicas SDK for MPEG2 encoding. It had an option for PCM audio but it was often distorted.
Episode 6 uses Main Concept SDK for MPEG2 encoding. Engineering decided to eliminate PCM audio with MPEG2 program streams and MPEG2 transport streams. I've been following your threads on Creative Cow with Craig Seeman....
Episode developers really don't see why AES (Audio Engineering Society) isn't the best audio codec for MPEG2. Episode uses the SMPTE 331M version.

Manzanita Systems
The PCM insertion is starting to become more popular driven by Netflix.
We will have a demo for you in a about a month.  Please check back with us then.

Sorensen Squeeze

MPEG-PCM is the only PCM audio codec available for MPEG files in Squeeze.
What about the MPEG PCM audio is not "passing muster" with them?
(My response about its compression has yet to appear on their forum)

Adobe Media Encoder
No real point in waiting for a tweak to AME w/ CS6 on the horizon. While largely overlooked, AME did scream through encodes and got high praise from QC. When analyzing the transport stream, I did get some errors not present in the 'others'.


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Paul Kakert
Re: MPEG2 Transport Stream w/ PCM Audio <-?!?!?->
on May 9, 2012 at 2:19:17 am

I am trying to encode for Netflix now too. A pixeltools.com solution they suggested is the only one I have seen that will do their specs, but it is a $1,500 solution. If anyone does have a solution, please share.

Paul Kakert
Storytellers International
DocumentaryTV.com


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Michael McIntyre
Re: MPEG2 Transport Stream w/ PCM Audio <-?!?!?->
on May 9, 2012 at 2:38:38 am

Hey Paul,

If you only need MPEG audio, any of the tools listed above will do it. This began as a search for a vendor-specific request for PCM audio wrapped in the MPEG transport stream. Per the specs listed @ pixteltool.com, they're using:

MPEG Layer1
48KHz
448 kbps

Not sure if you have Adobe Media Encoder (included w/ CS suites) but it is largely overlooked and screams w/ 64-bit processing. My tests yield great results. Episode 6 is $495 and $995 for 'Pro'. Sorensen Squeeze 8 is $699 @ B&H.

Maybe test-drive AME:
http://www.adobe.com/products/mediaencoder.html


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Michael Kammes
Re: MPEG2 Transport Stream w/ PCM Audio <-?!?!?->
on Oct 3, 2012 at 5:08:59 pm

Hello all-

Resurrecting this thread.

Wondering if Episode users have been able to generate a Netflix compatible file thus far.

And....what about 3D files?

My Netflix doc rev is A-5-21.

~Michael



.: michael kammes mpse
.: senior technology & workflow consultant
.: audio specialist . act fcp . acsr
.: michaelkammes.com
.: twitter: @michaelkammes
.: facebook: /mkammes

Hear me pontificate: Speaking Schedule .


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Michael McIntyre
Re: MPEG2 Transport Stream w/ PCM Audio <-?!?!?->
on Oct 3, 2012 at 5:22:13 pm

Hey Michael,

I actually never found a PCM solution. While my deliverables were in line w/ Netflix, they were for a different vendor who agreed to take audio as MPEG1 LAYER2. "Yeah - we get that a lot." I wished they'd told me sooner as I spent considerable time trying to find a PCM solution.

Debated contacting Netflix directly for a vendor referral to get their encoding workflow but stopped chasing after we got the 'other' audio okay'ed.

Best of luck and post to the thread if you find a way!

Thanks,

Michael McIntyre

Fever City Studio


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