HDV for MSPro7 official....

[Dr Mordrid]

HDV = the upcoming HD camcorders (using DV tapes) from Sony, Sharp etc;

http://www.ulead.com/aboutulead/press/pr11-17-03.htm

Dr. Mordrid

[Hulk]

Do you know what the specification is for this new format?
aspect ratio and compression?

Even if the final work is at standard definition, it's always nice to be able to work at higher resolution then the finished product.

Looking forward to the HD cams.

Mark

[Dr Mordrid]

HDV's stream specs are a 6-GOP (6 I-frames/sec vs. the typical 2 I-frames in NTSC) and it uses Main Profile/High-1440 Level instead of the typical-for-consumer-MPEG Main Profile/Main Level. Recording is to normal DV tapes. Interfacing is IEEE-1394 and aspect ratio is 16:9. Color sampling is 4:2:0.

The HDV spec supports;

1. 1280×720 at 25p, 30p, 50p, and 60p with an MPEG-2-bitrate of 19,000 mbit/s using an MPEG-2 transport stream. Luma sampling is at 74.25 MHz.

2. 1440x1080i at either 50i and 60i with an MPEG-2 bitrate of 25,000 mbit/s (same as DV) using an MPEG-2 packetized elemental stream. Luma sampling is at 55.7 MHz.

Stereo audio streams use 16-bit, 48kHz, MPEG Layer-2 at 384kbps.

Dr. Mordrid

[Brian Ellis]

I womder what kind of supercomputer will be necessary for RT????

[mmp121]

Originally posted by Dr Mordrid
2. 1440x1080i at either 50i and 60i with an MPEG-2 bitrate of 25,000 mbit/s (same as DV) using an MPEG-2 packetized elemental stream. Luma sampling is at 55.7 MHz.

I thought that the 1080i spec for HDTV was 1920x1080 ?

[Hulk]

Doc,

Two things:

As mmp121 states, 16:9 should be 1920x1080, right?


Also, could you explain this a bit further?

"and it uses Main Profile/High-1440 Level instead of the typical-for-consumer-MPEG Main Profile/Main Level"


And finally, how does 4:1:1 colorspace compare to 4:2:0 in a qualitative sense? By that I mean if you were comparing to clips at the same resolution with those two colorspaces.


Thanks,

Mark

[Dr Mordrid]

HDTV can be either 1440 or 1920 wide at 1080i but most consumer HDTV is 1440. This same horizontal compression at 1440 is used in Sony's CineAlta HD cams, which were the HD cams used for Star Wars - Clones.

MPEG levels define the maximum and minumum for image resolutlon, luminance samples/second, number of audio & video layers supported in scalable profiles and the max bitrate in a given profile.

In order from lowest to highest quality the levels are;

Simple (CIF; consumer tape equivalent)
Main (ITU (previously CCIR) 601; studio TV)
High 1440 (4x ITU 601; consumer HDTV)
High (production SMPTE 240 standard)

Now for some definitions;

Y = a luma (brightness) sample
Cr = Chroma red
Cb = Chroma blue

Decoders can calculate from Y, Cr and Cb to generate Cg (Chroma green) and from there all the colors you need within the limits of the video standard.

Broadcast signals use a 4:2:2 colorspace;



4:1:1 (as with NTSC DV);



This gives a color sample every pixel vertically, but only every fourth pixel horizontally. This lack of horizontal color samples causes each to be spread out over the subsequent 3 pixels, reducing the color resolution of a 1440 wide frame to only 360. As with NTSC DV this would make keying overlays a pain in the rump because of the highly aliased edges this causes.

MPEG-2 4:2:0;



This gives you a color sample every other pixel both horizontally and vertically. Even though you don't get a full set of color samples vertically the overall effect is much better for doing effects than 4:1:1.

Dr. Mordrid

[Jerry Jones]

Great information.

Thanks for the info!

Jerry Jones

http://www.jonesgroup.net

[Hulk]

Yes, excellent explanation.

Thanks,

Mark

[BrianP]

Just curious... which of the other NLEs (PPro, Vegas, XPressDV, Edition) support HDV? And by support I mean fully supported and implemented, not some half-a**ed pseudo-feature that looks great in the marketing PDF but falls way short in practice.

[Ray Austin]

Originally posted by Dr Mordrid
2. 1440x1080i at either 50i and 60i with an MPEG-2 bitrate of 25,000 mbit/s (same as DV) using an MPEG-2 packetized elemental stream. Luma sampling is at 55.7 MHz.

Dr. Mordrid

This bit-rate is what is captured by the camera? Transferring to computer would be the same bit rate or would it be different?

Just curious.

Also is it editable?

[Dr Mordrid]

It's the same bitrate as DV and it is what's captured by the camera. JVC includes the i.LINK Utility for transferring files from/to the cam until editors can do this directly.

Transferring is done by IEEE-1394 using either a packetized or transport stream, depending on which bitrate you choose (19kbps for 720P or 25 kbps for 1880i).

It will be editable once the MSPro7 plugin comes out around the first of the year. It can import the mpegs now, but the encoder can't export the correct GOP's, profiles & bitrates yet.

To edit HDV in Premiere Pro will require Cineforms AspectHD plugin, which only costs $1,200.00 USD

For now Vegas uses JVC's i.LINK I/O Utility for I/O. Looks to be a bit of monkey motion in Vegas until Sony issues a patch...which is likely as they're one of the HDV proponents coming out with cams this spring.

JVC is also bundling MPEG Edit Studio Pro 1.2 LE with the JY-HD10 for basic editing (also requires the i.LINK I/O tool though).

I would imagine most editors will eventually support HDV, but MSPro7 and Premiere Pro look to be first mid-range editors out of the gate.

Dr. Mordrid

[Ray Austin]

So then I am guessing there will be no need to recompress or encode to anything?

You just bring it in edit it and print to DVD and your set?

Obviously that high of a bit-rate won't work to well with current DVD's as that would get you in the neighborhood of 20min or so.

It looks like the same problem all over again... not enough room on the DVD.

[Dr Mordrid]

The bitrate for the HDV cams is about 3x the max allowed for DVD's, so some bitrate reduction will be necessary until blue ray or whatever HD DVD standard comes out with one equivalent to HDV or higher.

How this will affect the quality is up for grabs, but given that HDV uses a much shorter GOP there will be fewer B and P frames.

Dr. Mordrid

[miya]

Originally posted by Dr Mordrid
This same horizontal compression at 1440 is used in Sony's CineAlta HD cams, which were the HD cams used for Star Wars - Clones.


Dr. Mordrid

The Sony HDW-F900 records at 1920x1080 only. I know because I work with them every day.


.