Split Compression

[Gavin Greenwalt]

It's not a jpeg issue. It's in the uncompressed. I would be 99% confident that it's a codec 'feature'.

Jpeg2k uses multiple tiles which become apparent in noisy images. I was hoping RED wouldn't employ tiles but so be it, hopefully once CF cards increase in speed we can disable that 'feature'.

 

[Justin Anderson]

It's not a jpeg issue. It's in the uncompressed. I would be 99% confident that it's a codec 'feature'.

Jpeg2k uses multiple tiles which become apparent in noisy images. I was hoping RED wouldn't employ tiles but so be it, hopefully once CF cards increase in speed we can disable that 'feature'.

What if you just split the image into more tiles? Shouldn't that reduce the noise variation?

 

[Jannard]

This is a known issue with a fix on the way. It will be a simple firmware upgrade. We had it with Boris and Natasha, thought we fixed it and it resurfaced recently. We are on it.

Jim

 

[erbp]

This is a known issue with a fix on the way. It will be a simple firmware upgrade. We had it with Boris and Natasha, thought we fixed it and it resurfaced recently. We are on it.

Jim

Thanks for clarifying. Will the compression artifacts in the blue channel be fixed as well?

 

[Álex Montoya]

Nice, Jim.

 

[Steve Sherrick]

Thanks for clarifying. Will the compression artifacts in the blue channel be fixed as well?

Yeah, blue channel is really suffering. I certainly see some compression in the other channels as well, but not nearly as much.

Steve

 

[Graeme Nattress]

We're continually working to improve the compression in all it's aspects.

Graeme

 

[Steve Sherrick]

No doubt Graeme. This has to be a huge challenge trying to maintain high level of quality, yet keeping the size manageable for the format. Is it possible that we're seeing any weirdness introduced in these TIFFs? I'm really looking forward to seeing footage come directly off the camera to make a more hands on judgement.

Steve

 

[Graeme Nattress]

Yes, it's a challenge. It's doable, but a challenge. Each and every image you put through a scheme is different, and compression will act in different ways. As Jim mentioned, we saw this early on in B & N, but we put some more code in to stop it happening. That it's come back is annoying, but there's still plenty of things left for use to try!

Graeme

 

[Steve Freebairn]

Yes, it's a challenge. It's doable, but a challenge. Each and every image you put through a scheme is different, and compression will act in different ways. As Jim mentioned, we saw this early on in B & N, but we put some more code in to stop it happening. That it's come back is annoying, but there's still plenty of things left for use to try!

Graeme

Great news!, I'm sure you'll get it knocked out. So far, even with the minor issues, the footage still looks great.

 

[Steve Sherrick]

Graeme, I assume you have played around with some footage from the RAW port. Based on how good the images look in Redcode RAW even with some of these issues popping up, I imagine the RAW stuff must look even more breathtaking. However, from the beginning you guys have said it was hard for people to tell the difference when playing them back to back. Are these artifacts just tougher to see when playing back the 4K in motion on high quality monitor or projector? Are these things that people are just not catching until you look really carefully at stills? The footage I have downloaded that has been in motion has been .264 and any banding or other compression issues I have attributed to that codec.

Sorry for all of the questions. A lot of my curiosity about compression is directly related to a potential client's needs to do exteremly high end compositing and I am concerned about any issues that would give them reason to not use the camera.

Thanks,
Steve

 

[Nik Manning]

All I can say is I would have never saw that line and still don't really see it. If any one wants to switch my hv20 for their Red until they figure out this deal breaking problem I am right here for you buddy.

 

[conrad gaunt]

I have noticed the same thing way back when the first frames from "Crossing the line" were posted. I didn't want to mention it back then because it was from a beta camera.

I don't think the reason is that one particular channel is taking all the bandwidth. You can see the same effect in the following frame even if you don't watch a particular color channel. Observe well...

For a full frame: http://www.red.com/skin/img/gallery-still/009000.jpg

the split is exactly on the middle of the frame!

is that a wavelet based jpeg2000 or a normal 4:2:2 jpeg recompress? If it 4:2:2 it will screw with the blue, and the red a little too

 

[MikeCurtis]

I just LOVE the development process of this camera!

It used to be that a camera shipped, that's probably just how it was going to be, forever more. Minor, minor things could be tweaked with a firmware update, but it was often a fairly big deal to do so.

No more!

Get an email, load up a CF (soon SD) card with the fix, and you're off to the races with new/improved functionality.

In the 10 days I was in NYC with Offhollywood, I saw 2 firmware updates come in and multiple code builds as things ever improve. Not just fix, but IMPROVE.

I love it!

Even as software dev goes, these guys are INCREDIBLY fast. Forget hardware vendors - "Uhh...check back with us at NAB."

-mike

 

[jbeale]

A lot of my curiosity about compression is directly related to a potential client's needs to do exteremly high end compositing and I am concerned about any issues that would give them reason to not use the camera.

If you're at liberty to say, do you know what camera the high-end compositor would use instead? The Red compression issues I have seen so far are quite small in comparison to normal film grain, unless maybe you are shooting 65mm film or IMAX (?)

 

[Rob Lohman]

is that a wavelet based jpeg2000 or a normal 4:2:2 jpeg recompress? If it 4:2:2 it will screw with the blue, and the red a little too

We don't do 4:2:2

 

[Evan Owen]

We don't do 4:2:2

Not in the strict sense of the term, no. But all the shots I've seen show lots of resolution in the green channel, which doesn't seem to have any compression artifacts (visible anyway), while the red and blue channels exhibit significant compression artifacts and loss of detail.

At 4K, it doesn't seem to affect the image quality as much as 4:2:2 would normally, but you have to admit, there's not exactly an equal level of resolution among all three channels.

 

[Rob Powell]

If you're at liberty to say, do you know what camera the high-end compositor would use instead? The Red compression issues I have seen so far are quite small in comparison to normal film grain, unless maybe you are shooting 65mm film or IMAX (?)

I have similar concerns due to our compositing applications. It's not the compression that is the issue, per se. It's the fact that it is split. Trying to composit an image with settings that don't work for the whole image is problematic.

You're right, film does have grain, but at least it's consistent. While this artifact is not as noticable to the eye, it is exactly the type of difference that software could potentially lock on to creating varying noise patterns in a composited shot.

 

[Cail Young]

I have similar concerns due to our compositing applications. It's not the compression that is the issue, per se. It's the fact that it is split. Trying to composit an image with settings that don't work for the whole image is problematic.

As long as the compositor knows where the line is I don't see any problem - one already deals with spill suppression, holdout mattes, garbage mattes... a simple geometric mask shouldn't be too hard, but as I said, it means the compositor needs to know exactly where that line is.

 

[Graeme Nattress]

Sure uncompressed looks "better", but actually, the method of RAW decode / demosaic actually makes more difference to the end quality, so although I'm not using pristine Frankie uncompressed footage, the current compressed footage actually looks better.

Graeme