Optimum projection of ProHD footage

[David Knaggs]

This is a continuation of this thread:

http://www.dvinfo.net/conf/showthread.php?t=125086

which has probably strayed a fair way off its original topic about the availability of the ProHD DVD PLAYER SRDVD-100U. So I thought I'd start a dedicated thread.

Now, even JVC's own promotional blurb states:

"The smallest and most affordable HD Cinema production camera available! JVC's GY-HD110U opens a new area of digital cinematography, ... "

Okay, so it's a "digital cinema" camera. Yet most cinema-related posts in this forum over the past few years have concerned transfers to film. And even if someone does a digital projection at a festival or whatever, it's really so that a distributor will pick it up and "transfer it to film".

Therefore, with this thread, I'm specifically and only looking for "film-free" ProHD projection methods.

And the standard I'm looking for is "direct projection of ProHD footage to a paying cinema audience". (I.e. "non-festival".)

Now, we already know (thanks to Tim) that playing a camera-native .m2t file on PlayStation 3 (PS3) hooked up to an HD projector gives fantastic results (see the above thread).

So, I guess, if you had minimal color correction (created your "looks" in-camera) and minimal effects in your movie, then outputting it as a pure .m2t and playing it on PS3 hooked up to the projector might still give a very acceptable result.

So that's one method.

The other method I'm currently experimenting with (I've got an IT wizard helping me with this, fortunately) is a small purpose-built computer which will play the movie through software (we'll probably use a Linux OS and use an application such as "mplayer" to play the movie). This method also gives one the opportunity to install some security (anti-piracy) measures if one wishes. (To some, this will be an important consideration and, to others, perhaps not. But at least this method puts the option there.)

The major consideration in all of this is the selection of codec. Specifically:
i) Post-Production codec, and
ii) Projection codec.

If you have recorded your footage to tape or DR-HD100, then your images have already received an HDV compression. For the most optimum final results (after successive generations of the images through color correction and effects, etc.) it's best to use a "lossless" codec for post-production such as Uncompressed 4:2:2 or SheerVideo or similar.

In the perfect world, the projection codec would also be your post-production codec. Then you wouldn't lose quality through encoding from your post codec to a different projection codec.

Some of the projection codecs I'll be testing later this week are:
Native HDV
Apple Intermediate Codec (AIC)
H.264
JPEG 2000 (The codec of choice for Hollywood's DCI [Digital Cinema Initiative])
SheerVideo (10 different variations)
Uncompressed 8-bit 4:2:2
Uncompressed 10-bit 4:2:2

To do this test, I took a clip captured natively in Final Cut Pro (native .m2t file enclosed in a QuickTime wrapper) and exported it as a series of QuickTime movies, each in a different codec.

As a preliminary test, I opened each QuickTime movie on the computer screen, including the original clip. With ONE exception, you couldn't tell one from the other. They all looked terrific. Now, if you were to go through several generations of the image, then I'm sure that the lossless codecs would begin to stand out. But, with only a single transcode, they all looked great. And exactly the same.

Except for H.264!!!
It was tack-sharp. But the colors were off! They were kind of washed out (desaturated a little?) and a little brighter or less contrasty.

I was totally shocked by this. Isn't H.264 one of the main authoring codecs for a Blu-ray disc?

So I hope that I just made some sort of knuckle-headed goof with my H.264 export, as I'd earlier had H.264 listed as one of my favored projection codec options.

If others could test this for themselves (take a natively captured clip, place it in a sequence and export it as H.264, then open up both clips side-by-side in the QuickTime player and compare) and report what they find, I'd really appreciate it.

The only other thing worth mentioning is that my editing computer played each of the QuickTime movies really smoothly, except for JPEG 2000. The JPEG 2000 clip playback was very jerky and stuttering. I'm told that this is because the JPEG 2000 codec has a lot of "bells and whistles" attached to it. So I'm really wondering if JPEG 2000 is best played back through hardware rather than software.

Anyway, I hope that this thread might be used by others to share their successful methods for optimum ProHD projection. Perhaps someone has already blazed this trail! If so, it'll save me a lot of stumbling around.

[Sean Adair]

Hi David,
I've been following your thread from before, but have limited time to comment at the moment. I have a nice projector (Panasonic PT-AX200U native 720p).
Currently, there are 2 ways I can look at my own HD footage.
1/ HDMI out from my BR-HD50 deck
2/ 2nd monitor output from my mac
3/ HD-DVD player with DVD-R authored HD discs from DVD studio pro (also HDMI)

The latter is most interesting. Despite being an end-of-life product, hd-dvd was much more friendly for smaller production concerns. It was especially interesting since DVD-SP had this capability expressly designed to make HD programming on standard red laser DVD-R.
These discs are made with no special effort, by exporting from FCP to compressor, and adjusting a few settings. They are pretty universal in working with the Toshiba HD-dvd players (PS - under $100 these days). They also play back in any modern mac at HD resolution using the standard DVD player.
Unlike the blu-ray hacks, they can be authored with menus, buttons, scene selections.
While making discs for the PS3, has been established, it's my understanding that compatibility in set-tops is much less consistent.

One issue I saw with your earlier expressed workflow was that rendering/conforming was being used to make the m2T. It's this 2nd stage of mpeg2 compression that is challenging
to us. I think that by compressing for playback using compressor or a system other than the fixed rate hardware output, results can be better. 2-pass compression can certainly make a difference with mpeg2, and data rates can be dialed in a bit closer. There is a limit in what DVD-R can deliver in bit rate however, as Tim described, and higher rates also limit the programming length - although a dual-layer DVD helps. I haven't done extensive empirical testing, but I found H264 to be better, and I was using data rates higher than the original footage.

What is your workflow in creating the test compressed files where H264 disappointed you?
I suspect that somewhere there is a colorspace issue going on or inappropriate settings (perhaps web optimized?), and that this isn't a fault of the codec itself - what was the datarate for instance?. Yes, it's used for HD movie compression on blu-ray and hd-dvd, along with mpeg2 and a MS codec. As a more modern codec, it is supposed to give better performance at the same datarate.

I was also surprised that there isn't a way to reverse convert QT HDV files back to m2t, other than this clumsy process of outputting to tape and capturing again. Isn't it just a matter of putting a different "shell" on the compressed information, without any transcoding? Then there would at least be a way of quickly assembling rough cuts of native footage on disc (blu-ray or hd-dvd) without additional compression.

What I'm eager for is Apple to come out with a directly supported path to create and burn authored Blu-ray discs. The adobe path I've heard is still fraught with issues. This step will finally open up HD production to the next level for many of us.

Meanwhile, creating dvd-r discs can solve many display situations. A relatively low cost player can be set up for dedicated retail, shows, presentations with a burnt disc program. If it's a single presentation, taking the deck or camera for direct playback is hard to beat for convenience and quality.

The next big hurdle will be creating small run production. I'm used to doing runs of 100 or so dvd-r or 1,000 or so DVD pressed for authored SD projects here, and expected a much clearer path for these types of runs in HD by now. Licensing Fees, copy-protection requirements and equipment costs look like big impediments to this opening up soon. This was one aspect of the format war that looked a lot more promising on the hd-dvd side.

But I'm getting off track - this all probably belongs somewhere else on the forum, and I have an editing deadline to deal with. 2 camera JVC prohd studio shoot of self defense for women, looking great in HD, and due to be dumbed down for SD-DVD release in a few days....

[Steve Mullen]

Originally Posted by David Knaggs

Except for H.264!!!
It was tack-sharp. But the colors were off! They were kind of washed out (desaturated a little?) and a little brighter or less contrasty. I was totally shocked by this. Isn't H.264 one of the main authoring codecs for a Blu-ray disc?

1) I've found that exporting H.264 from a Mac that two overall corrections help: about a +5% increase in saturation and an 8% decrease in black level. The latter adjustment could better be replaced by an alteration of the gamma curve -- EZ to do on an Avid MC.

You can see my experiments on some very HIGH dynamic range video at:

http://exposureroom.com/members/DVC.aspx/

2) If you will be playing on the PC system you build, remember PC and Mac gammas are different. This bites folks who post on the web.

3) I LOVE HD DVD for this purpose because if your movies are < 20M you can burn on red-laser discs using DVDSP 4 or $50 Ulead MFP6. (You can get 40M on a DL disc.) BE SURE YOU USE AC3 2/0!

4) Lastly, Toast will burn AVCHD to red-laser discs that can play on NEW BD players. Burn at 17Mbps to 20Mbps.

[David Knaggs]

Thanks Sean and Steve for your great answers!

Originally Posted by Sean Adair

What is your workflow in creating the test compressed files where H264 disappointed you?
I suspect that somewhere there is a colorspace issue going on or inappropriate settings (perhaps web optimized?), and that this isn't a fault of the codec itself - what was the datarate for instance?

I made three separate tests with H.264.

1/ Direct export from FCP as a QuickTime movie,
2/ Export via compressor using the H.264 setting, and
3/ Export via compressor using the Apple TV (H.264) setting.

The specific workflow steps (all on the same Native HDV sequence) were:

1/ Direct export from FCP as a QuickTime movie
I selected File>Export>QuickTime Movie, then from the pop-up window under "Setting:" I scrolled down to "Custom" and selected it. From the new window, under "QuickTime Video Settings", I scrolled down the pop-up window next to "Compressor" and selected "H.264". I made sure that the Quality slider was set to 100% and then clicked the “Advanced” button. On that window, I slid the Quality slider in the Compressor to “Best”. Then I exported.

2/ Export via compressor using the H.264 setting
I selected File>Export>Using Compressor. In Compressor 3.0.3, I selected Settings>Apple>Formats>QuickTime>H.264. In the Inspector tab, I selected Encoder, clicked the Video Settings button and, in that new window, I slid the Quality slider under “Compressor” to “Best” and left Encoding at “Best quality”. Under “Motion” I checked “Automatic” next to “Keyframes”. Data rate was left at “Automatic”. Then I submitted.

3/ Export via compressor using the Apple TV (H.264) setting
In Compressor, I selected Settings>Apple>Apple Devices>H.264 for Apple TV. Then I submitted.


For the same 48.75 second sequence, the resultant file sizes were:
1/ 26.4 MB
2/ 165.1 MB
3/ 29.8 MB

And, just for comparison, I exported the same sequence as Native HDV and the resultant file size was 115.5 MB.

So it looks like the H.264 setting on Compressor applied the least amount of compression. It also had a higher picture quality compared to the other two, but all three (H.264) looked a bit "washed out" compared to the Native HDV clip.

Originally Posted by Sean Adair

I was also surprised that there isn't a way to reverse convert QT HDV files back to m2t, other than this clumsy process of outputting to tape and capturing again. Isn't it just a matter of putting a different "shell" on the compressed information, without any transcoding?

I was told by someone that an application called ffmpegX might be able to do it (both wrap and unwrap the QuickTime from the .m2t file). I haven't yet been able to figure out an approach to test this but, if it were true, it would really be like finding the "grail" as far as working with ProHD footage is concerned.

And I agree with your comments about the need for "proper" Blu-ray support.

Originally Posted by Steve Mullen

1) I've found that exporting H.264 from a Mac that two overall corrections help: about a +5% increase in saturation and an 8% decrease in black level. The latter adjustment could better be replaced by an alteration of the gamma curve -- EZ to do on an Avid MC.

Thanks, Steve. That's a very useful tip.
It's good to know that I'm not the only one to have noticed this H.264 export problem on the Mac. (I'm wondering if PC users are experiencing the same thing?) I've been suspecting that it might be an inbuilt gamma problem with Mac's H.264 QuickTime export and your comment about gamma curve adjustment tends to further confirm this.

Originally Posted by Steve Mullen

2) If you will be playing on the PC system you build, remember PC and Mac gammas are different. This bites folks who post on the web.

Again, thanks for the tip!

[Tim Dashwood]

Originally Posted by David Knaggs

I was told by someone that an application called ffmpegX might be able to do it (both wrap and unwrap the QuickTime from the .m2t file). I haven't yet been able to figure out an approach to test this but, if it were true, it would really be like finding the "grail" as far as working with ProHD footage is concerned.

I've been down that road (as well as VLC) in attempting to remove the quicktime encapsulation. Hours and days I will never get back!

[Steve Mullen]

Originally Posted by Tim Dashwood

I've been down that road (as well as VLC) in attempting to remove the quicktime encapsulation. Hours and days I will never get back!

About 4 years ago I wrote an application in C that made files that I could send to a JVC D-VHS VTR. I sold a bunch, but when DVHS didn't fly -- sales fell-off. I'll dig back into my files and find it.

I remember someone used it to make a DVHS tape with 5.1 surround sound for a festival. He was going to ship the deck to them. I guess now a PS3 would be the deal.

[David Knaggs]

I've been continuing my projection experiments. I even did an HD projection of ProHD footage compressed with the "H.264 for Apple TV" preset on Apple's Compressor. It was played out of a Windows PC using iTunes. It wasn't too shabby at all. (But nowhere near as good as projecting the .m2t from a Blu-Ray.) I also found a good solution to the "washed-out" look I was finding with H.264. I emailed Steve Martin of Ripple Training about it and asked if he could put out a tutorial on it. He emailed back and said it was a known issue and he simply adds a .1 gamma filter in Compressor before outputting. I ended up adding a .11 filter (Inspector>Filters>Gamma Correction>1.11) and it worked very nicely with my particular footage.

I came across this player (US $130) by Western Digital yesterday:

WD TV HD Media Player ( WDAVN00 )

Amongst other things, it plays .mov files in both H.264 and MPEG-4 (presumably the MPEG-4 is the .m4v file from the Apple TV preset?). It also plays MPEG-2 files. I don't know how it handles Transport Stream files such as the .m2t (one reviewer said that he had to change his extension from .TS to .MPG as the player won’t recognize .TS files).

I'm hoping that the WD player plays each movie out through hardware (in a similar vein to a DVD player or Blu-Ray player) rather than software. I've found that software players run the fatal risk of stuttering playback, plus the way Windows plays a movie through QuickTime or iTunes always looks "off" to me (even allowing for gamma differences between Mac and PC).

Has anyone tested the WD player with ProHD footage yet? (Either projected or on a large HD TV?)

I'm really hoping that the WD player will give as good a result with ProHD footage as Blu-Ray does.

[Marc Colemont]

I use since a few weeks a MiniMac to play the 720P Files on my Plasma.
I used Cineform AVI, and ProRes, and H.264 as a test.
The ProRes is a bit on the limit for the harddrive, H.264 works well, but the Cineform codec gives the best quality comparable with ProRes result without hickups from the drive.
The H.264 was tested with the 'AppleTV setting' in compressor, and H.264 export from FCP.
The AppleTV preset compression was visible through some artifacts.
That was actually the reason why I didn't took a ApplyTV vs MiniMac as it uses too compressed H.264 settings for my taste.