Avid uncompressed HD

D

D_and_G

Well-known member
Looking at stepping up to the HD plate (with HVX200) and eventual film out -

From everything I've seen, there are two options.

1. Ingest uncompressed HD, edit it in a 10 bit environment (monitor + cc with SDI out
etc...) then output to online session uncompressed or high rate photo JPEG/TIFF.

2. Ingest in the native DVCPRO HD codec, edit in that native codec, then output
uncompressed to online cc and film out.

The advice I've seen is it is better to edit in a 10 bit uncompressed environment, due to the better colour space and you step on the image less (important for film out).

Now instead of spending $10, 000 or more for cinewave/Final Touch HD etc... on top of the rest of a new HD suite cost, I'd like to remain in Avid.

So - long way round - Does Avid Xpress Pro HD allow uncompressed DVCPRO HD ingest, and allow to edit in the 10 bit environment ? (I know this is possible with FCP + Aja Kona 2/ Blackmagic)

If not, how do you monitor true ( not DNxHD) HD, without an SDI out ?

From reading the boards, I'm am getting an inkling that only an Adrenaline suite can do this ? And Mojo has no SDI out for true HD cc ? Sorry about all the questions, but I'm narrowing down my preferred workflow.
 
It does get confusing really fast, so I'll give you my understanding of the workflow. Hopefully MichaelP will chime in and correct me anywhere I need correcting. :)

Xpress Pro HD natively can ingest DVCPRO HD and does so in a 10 bit environment. Your question about "uncompressed DVCPRO HD" confuses me. That's like asking for uncompressed DV. Inheret in the format there is compression being used, so if you capture the footage in its native codec you have a 1:1 relationship with the video that was shot. To capture that same video uncompressed has always seemed a waste of space to me. I've heard the arguments that you can tell a difference, but to me I'll take a digital copy of the media any day. So, Xpress Pro HD will allow you to edit in native DVCPRO HD. Also, I can't imagine the amount of machine it would take to edit in a 10 bit uncompressed HD environment.

Now for your CC, I understand capturing uncompressed. Mojo is not going to help you there. It is an 8-bit machine. Sadly, for as much as I like Mojo it's started showing it's age faster than I expected. Mojo does down convert HD footage to SD for viewing on a monitor, but that doesn't solve the problem you posted. The practical answer is probably to online the footage on an MCA or higher.

Finally, what's wrong with DNxHD? It's brilliant for what it was designed for, and it is a mastering codec, so there should be no fear in using it.

To sum up, you'll probably need to go with your number 2 suggestion, and plan on doing your online session with an MCA or better.

Hope that helps.

Chris
 
There is no such thing as an uncompressed HD camera format unless you are shooting directly to a stack of hard drives bypassing the compression codecs in the camera. There is a lot of confusion between native HD editing and uncompressed HD editing. Even the press gets this wrong and it drives me crazy! I hear all the time, "it has the ability to edit uncompressed HD off a laptop..." I think not. HD is ~1.5GB/second. DVCPRO is 100MB/second, HDCAM is 140MB/second. Then you get into color space and bit depth. Each of these affects performance on an editing system.

The workflow from a HVX200 shooting 720p/23.976 directly to a P2 card would be to copy the media directly to the MediaFile folder and start editing in a 720p/23.97 project type. You can even edit directly off the P2 card if you want.

As far as mastering, you can stay in a DVCPRO format the whole time and see the image back out over the FireWire to the deck and the deck attached to a monitor. This would be your lowest cost solution. There is no 10 bit native video on Xpress Pro but color correction is done in 10 bit space. If dealing with multiple renders and generations, you can always render to one of the DNxHD format which holds up much better over multiple generations. But if you are doing mainly straight cuts, dissolves, and color correction, do everything as DVCPRO 100 using the native codec. Then you output back to the deck or export as sequential TIFF files for a film out elsewhere by selecting RGB as the export color space.

If you want real time SDI and monitoring, you can take you entire project and media, open it up on a Media Composer Adrenaline and hit play or use the newly announced Avud Symphony Nitris for real time color correction and effects for output.

Michael
 
Thanks for your input. It's appreciated.

So the deck connected to the avid, serves a similar function as the Kona 2 card in FCP ?

Also as to DNxHD, the editor I talked too said that if your going to filmout you don't want to step on the image, and using DNxHD would be putting it through another compression algorithim - essentially degrading it. Ideally when going to film out, using HD you want to put the datastream through as few hoops as possible.

I understand DVCPRO is 4:2:2 and if it were truly uncompressed it would be 4:4:4.
I'd like to do as much postproduction in house as possible before going to an online session. So with a deck I'll have the same fuctionality as FCP ?
 
Let me be a little clearer as I now realize what you are really asking. DVCPRO, like DV50 and DV25 all behave in the same manner and other than the differences in SD and HD resolutions, your workflow choices will be similar.

But you still need to decide whether you want to edit DVCPRO natively or uncompressed. If we use the DV25 example, you can capture DV25 natively over FireWire, edit, color correct, render, and output as DV25. The same goes for the other formats. DV25 and other formats have gone on to film outs with very good results (Incident at Loch Ness was done this way from Xpress Pro).

But in each of these cases, whenever a render is performed, the DV25 is decoded to an uncompressed stream, the effect added, then rendered back do a DV25 format. It is when you start doing multiple generations of this that artifacting will occur because of the decompress and recompress stages. If you were to capture your DV25 via SDI to an uncompressed SD signal, then you are not suffering the generational loss of renders.

The same can be said of DVCPRO100, you can always take the decompressed full uncompressed HD signal from the SDI connection and work in an 8 or 10 bit uncompressed HD format for all your work. This is not possible on Xpress Pro or Media Composer Adrenaline. Uncompressed HD is available on Symphony Nitris and DS Nitris.

As far as DNxHD, compression can be done in a variety of ways and the DNxHD codecs were designed for the post process and does not suffer the generational loss of other camera type codecs. I recently did test where I took 2K scans and rendered one as uncompressed 10 bit HD and the same files as DNxHD 220 10 bit. I did a split and exported the sequence as DPX files. The files were then output to 35mm film. the DPX files were also viewed on a 2K projector in a high quality color correction room which is far more less forgiving than film and no one to this day has been able to tell me how the split was done, not which side is which.

A lot of this depends on your workflow and budget.

Michael
 
Thanks Michael !

That clears it up. You're a real mate (the best compliment I can give).

Cheers.
 
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