Film-Tech Forum ARCHIVE: Best export format from ProRes 422 for E-Cinema?

This is topic Best export format from ProRes 422 for E-Cinema? in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Randell Kelly (Member # 9897) on 03-14-2017, 10:19 AM:

Hi Everyone. I am new around here, so I apologize if this is the wrong area to post this in. We do the AV production work for a horror movie film festival in the Dallas area. Texas Frightmare Weekend. I have an e-cinema server I built that uses VLC to play the films. I am working with some of the film producers and directors to try to get them to move from bringing blu-rays to a digital format. A few have mentioned they have the file in ProRes 422. What export type would you guys recommend they give me?
I am also working to enable playing DSPs. I purchased DCPPlayer but need to upgrade my graphics card before I can test it out.

Posted by Carsten Kurz (Member # 5396) on 03-14-2017, 10:48 AM:

If they have ProRes files, why don't you play these directly? If you don't have/use a DCI server/player, it doesn't make sense to go the DCP route.

- Carsten

Posted by Randell Kelly (Member # 9897) on 03-14-2017, 11:01 AM:

I read some where that the ProRes 422 stuff is best for editing but not playback so much. If that's not the case I need to figure that out. All of the DSPs I would play are not encrypted (all independent films) so DCI hardware shouldn't be required. Granted I am just starting to get into this higher end of festival cinema so I could be wrong with all this. What I am looking to deliver in the end is:
1. Most compatible format. No burning or glitch issues from optical.
2. Ease of distribution for the producer/director
3. Highest possible quality. (within reason/Hardware cost)

Posted by Jim Cassedy (Member # 4115) on 03-14-2017, 02:43 PM:

Ok- - I can't claim I'm an expert in this particular area, but I've had to
deal with this kind of thing on a regular basis for the last 7 or 8 years.
So when I first started doing that, I did a lot of "Google-ing" and it
seems that ProRes 422 is fine 99% of the time

Generally speaking - - unless you're projecting onto a huge screen,
or dealing with 4K, the extra huge file sizes of 422HQ aren't going
to buy you that much more image quality.

Also, from notes I took when investigating this- -
422HQ which has a 10bit pixel depth, isn't going to make something
mastered with an 8bit pixel depth (which many projects are) look any
better. Also, 422HQ requires a much higher data transfer rate to play
properly, which, depending on your combination of software or hardware,
may be tricky to achieve. I was recently called in to troubleshoot playback
problems for a local event which was using ProRes 422HQ & was experiencing
playback problems. Their entire issue was that their hardware couldn't
handle the extra data rate of 422HQ. (7200rpm drives are almost a must)

Long story short- - I've been using plain old Pro-Res 422 for several
years at dozens of small & large film festivals and corporate events.
- - and I've never had any complaints from either attendees or the
film makers about image quality. IMO 422HQ is overkill. (Sure, you can
buy a car that goes 200mph, but how often do you need to go 200mph?)

That's my .02cents worth, based on my personal experiences.

Here's some info I've had filed on my computer for some time explaining
the difference in Pro-Res versions, mainly as they apply to editing, but I
kept it because it explained the different pro-res formats in 'plain language':

ProRes 4444: virtually lossless, extremely high-fidelity codec, only to be
used with high-end acquisition formats such as HDCAM SR, AVC-Intra and
the likes, AND when doing high-end multiple generation compositing or
keying OR when you need to export high-end video with alpha channel
(roundtripping to third party applications).

ProRes 422(HQ): virtually lossless codec, only to be used with high-end
acquisition formats such as HDCAM SR, AVC-Intra and the likes, AND
when you need high-end compositing or keying.

ProRes 422(regular): virtually lossless codec to be used with most
common acquisition formats (HDV, EX, AVCHD...) and when you
need multiple generations in editing or compositing (multiple layers,
renders or exports).

ProRes 422(LT): relatively lossless codec, to be used with most
common acquisition formats and where no heavy editing
or compositing is involved.

ProRes 422"Proxy": for first generation viewing and editing (cuts only).

Posted by Carsten Kurz (Member # 5396) on 03-14-2017, 03:34 PM:

I think someone brought up the idea that the ProRes 422 format has a certain weakness that makes realtime playback unreliable. That is not true. If the ProRes file is technically ok, it is more likely that the playback application is doing a bad job.

- Carsten

Posted by Mike Schulz (Member # 4297) on 03-14-2017, 04:29 PM:

I concur with what other have said here, if you have a decent playback device, then there should be no problem with playback on Prores422.

At one of my high profile venues, we use the rack mounted Aja Ki-Pro (which uses ProRes as its native playback format/codec) to handle all of our alternate content and pre-show. I'm not sure how much it would cost to purchase one of these but I know you should be able to rent a deck for an event fairly easily. That might save you more time and money than to convert everything into a DCP or pay to have some other shop do it for you.

Posted by Randell Kelly (Member # 9897) on 03-15-2017, 11:50 AM:

Thank you for the info guys. I upgraded the graphics card last night and I can now play the test DPCs I have. Unfortunately I discovered that DCPplayer does not allow playing the film on a separate screen. I would have to drag the app to the projector window then go full screen. I don't want the viewers seeing all the app interfaces since I am trying to get this as close as I can to a theater feel. VLC work beautifully for this on just about every other format other than DCPs.

So for the ProRes422 encoding, those always have a .mov wrapper correct?

As for the hard drive speed I built the server with a 1TB SSD. 1 partition for the OS and a second partition for the films.

Posted by Scott Norwood (Member # 30) on 03-15-2017, 12:27 PM:

Agreed with the recommendation of the Ki-Pro. It works well, if you can get the content in the very specific format that it requires. The only significant limitation that I have found is that (unless there have been recent firmware changes) it is not possible to make a playlist of titles with a mix of frame rates.

These go for about $3k new and rent for about $150/day or thereabouts, so they are pretty affordable. They also have pretty much every I/O connection you could want (HD-SDI, HDMI, component analog, etc.). This is less of an issue with D-cinema projectors, but can be important if one needs to work in a venue with an existing audio-visual-type video projector.

Posted by Antti Nayha (Member # 4980) on 03-18-2017, 05:06 AM:

quote: Jim Cassedy
422HQ which has a 10bit pixel depth, isn't going to make something mastered with an 8bit pixel depth (which many projects are) look any better.

All ProRes 422 variants have a 10-bit sample depth, the only difference is the bitrate. The nominal/average bitrates for 1920x1080 24p content are:

ProRes 422 HQ: 176 Mbps
ProRes 422: 118 Mbps
ProRes 422 LT: 82 Mbps
ProRes 422 Proxy: 36 Mbps

I've done a few tests with extremely grainy, difficult-to-compress material, and I could see absolutely no difference between 422 HQ and 422 even when zooming in on a still image. So yeah, HQ is definitely overkill for projection purposes, no matter how huge the screen. And like Jim, I've also experienced cases where the playback equipment couldn't handle HQ's extra bitrate – note that ProRes is not a constant bitrate codec, so the bitrate rises even higher when encoding very grainy/complex material.

I would go so far as to say that even ProRes 422 LT is perfectly fine for projection, too. I'll have to do some more close-up tests at some point, but even if they do show a difference when zooming in on a freeze frame, I doubt that it's actually visible on a moving image.

ProRes 422 Proxy, on the other hand, is definitely visually lossy and should be avoided for this purpose.