Video On Demand - Encoding For

[scottrwn98]

Greetings. This may be a trial and error process, but the television station I work for says they can put "Files" on their server ... only problem is they have to be encoded a certain way (e.g. 3.75 bit rate)

I'm a filmmaker and I author a DVD with the film in 16x9, 23.976 fps and Dolby Digital AC3 audio) ...

The encoder guy takes my DVD and drops it in a standard player, and has the player linked to a Hardware Encoder (which encodes the movie AGAIN and down converts my 5.1 to Stereo).

Now, does anyone know the "proper" format to encode a MP2 for a Video On Demand server or any regular server?

Our Tech person said the server can read MP2 and AC3 files, but what specs do I encoded them with? I hope to de-engineer the files from the server, but I didn't want to waste a week with Trial and Error. Does the MP2 need to be transport stream, or what?

Thanks !!!

[Baldrick]

doesn't the tech person now the specs?

[edDV]

First step is to define your target customer and his-her technical ability to receive the video.

Second step is to make it easy for the target customer to acquire the video.

Third step is all marketing. How do you let them know the video is there. Convince them that they need to download it. Support them if they have difficulty.

[Cornucopia]

I'd say you should get a copy of one of the files on the server. Sounds like it should be an MPEG2 or MPEG4.

Open in Gspot (beta version). Hopefully, it will tell you enough info where you can directly encode your film ONCE and retain the best video and audio quality.

If the tech/encoder guy knows the specs, find them out and post here. We could give tips for best method to get to final type.

Scott

[scottrwn98]

The tech guy doesn't know, other wise we would not only put VOD programming on the server (such as our local shows) but we could encode our commercials to our scheduled server. The DVD player hooked up the the hardware encoded is his only option (which sucks).

I did find a PDF from CableLabs for "Video On-Demand Content Encoding Profiles Specification." This might work if I (and ProCoder) can relate to its specs.

[edDV]

I'm looking at one of the mov videos.

I'll try to be fair. It is a typical student project using Maya or similar to simulate 80's movies. If you guys only knew how difficult this was back then. I doubt you will be a candidate for the SIGGRAPH peer awards with this (going to Boston?). You have spent too much on a website designer. You are not yet worthy (Wayne's World context). Excuse the tough love.

Even so, I encourage you to find:

1. a script writer
2. a tech person that can communicate details on the forums
3. a marketing person to make you all look good to potential employers.

Please direct us to your best work.

PS: I hope your credits include Douglas Adams "Starship Titanic".

[scottrwn98]

Huh ... ?

[edDV]

Real world brother.

I'm on your side.

[scottrwn98]

I didn't expect a critique on our work. (critique is always good, but I'm not asking for it in this post).

Also, I am the web designer. Most of that content on the website is 2 year+ old.

[edDV]

Tell your employers that the web design is good.

Get the tech person to help ask the questions.

[scottrwn98]

Thank you!

I'm very satisified with how I designed it.

I already said he doesn't know ... This is why I'm asking on here ...

[edDV]

Need more detail to the question. What are you trying to do? What are the file formats? Who is the target customer?

[scottrwn98]

I will say this again ...

File format: MPEG2

Target Customer: ... ... ?? ... There is no target customer, its Video On-Demand ... anyone can access it.

What am I trying to do: ... ... I want to ENCODE my MOV file as an MPEG2 to UPLOAD to our VOD SERVER so the SERVER can read it ... the way they do it now is use a DVD PLAYER HOOKED UP TO A HARDWARE ENCODER ... the HARDWARE ENCODER makes the MPEG2 file on the server. There are about 100 ways to encode an MPEG2 ...

I'm ASKING what is the CORRECT SPECS to encode a MPEG2 file that the VIDEO ON DEMAND server will like. ... transport stream, CQ, VBR, CBR, what?

Rather than wait for the tech man to give me an already encoded MPEG2 file from the server next week, I'd like to start researching it now.

[edDV]

I was able to play the MOV files you have up there now with a DSL connection no problem.

Why MPeg2? If it is for dialup, MPeg2 will take forever. You need a more compressed format for that.

If this is a TV station VOD server, they will tell you the specs they support.

[scottrwn98]

This is the last time I will say this ...

The TECH guy DOESN'T KNOW! ... because the company ONLY has HARDWARE ENCODING. The Hardware makes the MP2 file for the server. They do not use software, .. in fact, most of the encoding is realtime for shows. All they know is MP2 and 3.75mbps. This is the only specs they know.

I want to solve this puzzle!

I have Highspeed internet ... I don't care about downloading MOV files, that is not what I'm talking about ... please listen ... no video will go on the internet ... as you can see in the SUBJECT ... it says Video on Demand - Encoding For.

Company's charge lots of $$$ for a single codec linked to Hardware to put programming on cable (not feeds from networks) just for putting commercials and movies.

Cornucopia has the right idea ... take a current file from the server and de-engineer it ... I would, but our tech person is out of town until Monday, so I'd like to do as much research as possible.

[edDV]

This is the last time I will say this ...

The TECH guy DOESN'T KNOW! ... because the company ONLY has HARDWARE ENCODING. The Hardware makes the MP2 file for the server. They do not use software, .. in fact, most of the encoding is realtime for shows. All they know is MP2 and 3.75mbps. This is the only specs they know.

I want to solve this puzzle!

I have Highspeed internet ... I don't care about downloading MOV files, that is not what I'm talking about ... please listen ... no video will go on the internet ... as you can see in the SUBJECT ... it says Video on Demand - Encoding For.

Company's charge lots of $$$ for a single codec linked to Hardware to put programming on cable (not feeds from networks) just for putting commercials and movies.

Cornucopia has the right idea ... take a current file from the server and de-engineer it ... I would, but our tech person is out of town until Monday, so I'd like to do as much research as possible.

A puzzle it is but I think you gave some clues here.

VOD is usually a download service for either internet or cable. Let me guess and it is only a guess from the info provided.

Guess 1: You are trying to upload to a public access channel's playout server on cable? Those people usually want a tape. Locally here the tape can be S-VHS or MiniDV format. The tape gets played into the realtime MPeg2 encoder and 3.75Mbps is one of the possible compressions on a Tek Profile or a SeaChange server.

Guess 2: IPTV? 3.75Mbps is also one of the SD resolutions for IPTV distribution.
http://www.ineoquest.com/page263.html
http://www.kasenna.com/downloads/datasheets/Kasenna_Media_Servers_Datasheet.pdf
http://www.tektronix.com/Measurement/App_Notes/2A_17186/eng/2AW_17186_0.pdf

Did I guess right?

[scottrwn98]

Video on Demand is on our first channel (01) ... so yes, We take our DVCPro Tapes and run them through the Hardware Encoder (which can be anything from the Friday High School Football game, to our local Cooking Show). It is not public access, that is a completely different channel. Public Access is channel 19 on our regular channels, like channel 11 (PBS).

Video On Demand can have sub menus that our tech guys have setup so if an old Person wanted to watch our History Episode of KU Football, and missed regular programming, he can pull it up on Channel 01 and watch it.

We spoke with our Marketing Manager for cable and she said they can add an option for "Short Films" and we can bring a DVD with a short film to our Tech Guy and he would encode it to the server.

He's boss said they can look at the files on the server (e.g. shortfilm06-6-2006.mp2 ... not sure if that is correct file name) .. this file was created through the Hardware encoder. And I believe SeaChange is correct. He said they go by CabelLabs rules for encoding. If I could find out what that mp2 file was made of, ... I could encode my DVD (m2v) and encode the film as mp2 (or whatever extension, m2t) to burn to CD-R ... then the tech guy would copy that file to the server to replace ... shortfilm06-6-2006.mp2 and when people would select that film from VOD, it would play ... no re-encode from a DVD to mp2, the AC3 would not be down converted to stereo.

My problem is, what properties do I set for that m2t? GOP, I-Frame settings, 23.976 flagging to 3:2 pulldown, etc.

I have a PDF of rules and specs, but I won't find out until tomorrow if this will work.


Can you tell by my typing, that I'm exhausted?

[edDV]

Here you go, this is the CableLabs Media Specification for SD. See Chapter 4.
http://www.cablelabs.com/projects/metadata/downloads/specs/MD-SP-VOD-CEP-I01-040107.pdf

Interesting how specific this spec is.
480i at 528x480 or 352x480
Black at 0 IRE

Dolby Digital at 384 kbps for Dolby 5.1, when available, and 192 kbps for two channel stereo when Dolby 5.1 is not available.

Encoding shall be CBR
The sum of the video and this selected one audio shall not exceed 3.75 Mbps.

Interesting that they find sports material encoding inadequate at 3.75 Mbps 528x480 and recommend dropping resolution to 352x480 at that bitrate.

[scottrwn98]

Yeah, I downloaded this yesterday evening and read the specs. Now I'm trying to see if I can sync these specs with ProCoder.

I guess I save as a m2t file.

I wonder why 528x480 instead of 720x480 (other than saving space)?

[jayl]

I don't know that this will be at all helpful to you, but we use a similar hardware encoder for our internal video on demand server here. It is a Vbrick encoder that transcodes the video into MPEG-2 or MPEG-4 transport streams.

Currently, I do what your tech basically does. I play the video from a DVD through a DVD player patched into the hardware encoder, which transcodes it in real time into a format it likes. It also scatters the data all over the server when it does so, meaning that there is basically no way (that I know of) to just pull the file off the server in a flat file.

[edDV]

528x480 is adequate for SD display of NTSC. 528x480 was chosen for cable SD MPeg2 channels as the best compromise of picture quality to #channels made available.

A state of the art cable system will use 528x480 but bitrates are usually higher than these VOD specs. Bitrate quality varies by channel. Here SD HBO gets ~7-8Mb/s. At the other extreme, some talking head channels get ~4Mb/s. HD channels get 20 or 25Mb/s. These rates are set locally.

Older cable systems use 352x480 and cram 8-10 MPeg2 channels into one 6Mhz QAM channel.

Dish (original system) uses 480x480. I forget what directv uses but it is no more than 528x480.

[scottrwn98]

Really ...

SURELY there is a way to add files to the server. Our head-tech guy says they can access the files, but didn't say they were scattered.

Any suggestions on how to do this? I've taken files from the server to transcode to DVC Pro, but it was some weird Codec. It was so long ago, I don't remember that it was.

[edDV]

Yeah, I downloaded this yesterday evening and read the specs. Now I'm trying to see if I can sync these specs with ProCoder.

If I were in your shoes, I would call Canopus ProCoder support. They probably have this all worked out and can send you the settings.

[scottrwn98]

The Encoder is a Tandberg E5710 ... not that it helps.

So is it possible to tell ProCoder the specs in that PDF (CableLabs Specs)?

Our tech guy said the file extension is (*.mpg) ... not m2t, m2t ...

I appreciate everyone's help.

[edDV]

Your other option has always been to render to DV standard 4:3 720x480i 29.97 and record to tape. They would play that tape into the Tandberg E5710 and everyone would be happy.

[scottrwn98]

Read my very first post ...

[Cornucopia]

I think what edDV was trying to say was:

You've already compressed it alot for the DVD. Recompression isn't a good idea.
Much better to compress to DV tape ("lighter" compression). Then the recompression won't do as much damage.
Since the Tandberg has both CompositeVideo+BalancedAudio connections (which the DVD player is likely using) AND Digital SDI connections, you could have a DV deck that has SDI output (like the Sony DSR-1500 w/SDI daughtercard option), and switch between input choices. Quality would be drastically better.

Better still would be non-realtime software encoding (like Procoder) from uncompressed master--IF you can get it onto the server via a network (or sneakernet+upload).

Note: Regardless of what your IP tech guy said, the output from that encoder box is MPEG2 Transport streams (aka M2T, MT2). Audio outputs are determined by which option card you bought into, but I would guess that AC3 2.0 or MP2 2.0 is most likely, as these would be the most supported by VOD clients/users.

You ought to have enough specs to go now....
MPEG2 Transport stream
MP@ML w/ 8bit 4:2:0
528x480 (w/4:3 DAR usual, although 16:9 DAR may be possible) @ 29.97i
CBR encoding, w/ combined A+V bitrate of 3.75Mbps max, so V should be ~3500kbps and A should be 192kbps.

If you can't do M2T's, make MPEG2 program streams and then pass it through a muxer/remuxer, like Elecard's or PixelTools.

Scott

[scottrwn98]

Awesome, Thanks! I will try that when I get home.

No, what I was saying to read my post was ... I mix my audio in AC3 format and the server can take that format. I didn't want to downmix my audio to Stereo (reguardless if it is DVD or Mini-DV, DVCPro or Beta).

Montu just informed me that the man that works with us (for SeaCharge) can access the files on the server and if I can get a hold of one ... next week, I can begin de-engeering it.

He told me that the MPG file has both Audio and Video embedded. So somehow, I have to create a MPG file (with MPeg2 528x480, 23.976->3:2 .. and AC3)

As a filmmaker, its nice to work for a company that owns a Newspaper company, ISP company, Television / Production Studio and Telephony.

[edDV]

Read my very first post ...

... only problem is they have to be encoded a certain way (e.g. 3.75 bit rate)

I'm a filmmaker and I author a DVD with the film in 16x9, 23.976 fps and Dolby Digital AC3 audio) ...

The encoder guy takes my DVD and drops it in a standard player, and has the player linked to a Hardware Encoder (which encodes the movie AGAIN and down converts my 5.1 to Stereo).

So we know now the 16:9 won't work without letterboxing and audio needs special handling for 5.1 to work.

So is your problem letterboxing and 2 channel stereo? The VOD customers probably don't care. Very few have 5.1 capable cable boxes.

You need to help us by describing your problem to be solved in detail. It should be fairly direct to edit a DV format letterbox 2 channel stereo version of your program or even a Pan/Scan 4:3 version.

3.75Mb/s is very iffy for letterbox. Comcast here does mostly "full screen" movies with 2 channel audio over "On Demand" SD VOD. They do have HBO Sopranos in 16:9 with 5.1 dolby which looks marginal but proves they can do it. It looks highly compressed to me.

Without fully understanding your problem, I would
1st make a DV format tape, or
2nd call Canopus for proper Procoder settings for CableLabs 3.75 Mb/s VOD standard.

It will still playout telecined of course.

[Cornucopia]

Actually, if the DVD player is playing out via Composite + 2ch balanced analog audio, THAT is what is the limiting factor in the re-encoding. The encoder is just seeing an Analog signal and using a DEFAULT? setting.

But it looks like the encoder can do pulldown, which means that your progressive @23.976 might work if you could bypass the encoder altogether and upload your own encode to the server.

Why don't you render a ~2 min. clip, using your "best/hopeful" settings, to AVI/MOV and then encode a batch with different options each:
4:3 vs. 16:9
Interlace 29.97 vs. Progressive 23.976 (w/TC flag inserted)
AC3 5.1 vs. AC3 2.0 vs. mp2 2.0

If 5.1 won't work, you should at least try Dolby Surround encoding on the 2.0 (and flag it in the AC3 2.0 encoding), that could retain some of the surround-ness.

If you can do the 16:9 and the Progressive 23.976, you'll be making much better use of your available bitrate (IOW, the cable box will be doing the stretching and telecine-ing after broadcast reception).

Scott