First REDCODE image!

I would assume that the reason 100x compression will not be available is that it is not possible for the camera to do in realtime. From Jim's description it sounds like the footage was captured Raw (real raw 4.9k) and then Redcoded in post.

But why was it cropped to 4k?

Also, can someone tell me the difference between "Active Sensor Array" which is 4520x2540 and "Full Sensor Array" which is 4900x2580? Why is there a distinction between Active and Full.

These images look amazing.
 
billy fattey said:
But why was it cropped to 4k?
Click to expand...

I think REDCODE has only ever been mentioned for use up to 4k, not 2540p. I assume 4k is the most it can do in real-time in camera, so I guess they cropped to 4k to emulate this.
 
There are some block borders (for all sorts of reasons) in the full array. You crop those out to get the active pixels.
 
billy fattey said:
Also, can someone tell me the difference between "Active Sensor Array" which is 4520x2540 and "Full Sensor Array" which is 4900x2580? Why is there a distinction between Active and Full.
Click to expand...
I believe (and I may be very wrong) but full sensor array is the physical size of the sensor but it crops off the edges to 4520x2540 in order to retain the same aspect ratio as others industry standards (In other words the same shape rectangle).

1080p = 1920 × 1080
2540p = 4520 × 2540

If you used the full sensor array the images you capture would be the wrong shape. Whilst I'm not 100% I believe that film has the same aspect ratio and so by continuing to use it with digital cameras it means that all equipment used whether accessorieslike lenses or projectors, as well as editing between film or digital all fits to a standard.

I think it'd be an aspect ratio of about 1.78:1. Obviously what you see at the cinema crops the image at the top and bottom to make it 2.40:1.

Like I say though I'm no expert so if this is wrong then please feel free to step in and set me straight.

Congrats on the new images, they're looking great, it also kinda makes me wish I'd reserved a 300mm lense now... you shoulda released these images last week!
 
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This is truly amazing. The depth of field is sweet.


Oh, and Actors will definitely nees to clean their ears and noses well for this camera.
 
The camera could do this level of compression in camera, but I think we're going to improve things significantly in camera compred to the software prototype that Jim is using today.

Compression ratios are funny beasts and you can get funny results with them. The 100:1 is about right if you think RGB, in that the uncompressed tiff is about 100 times bigger than the compressed file that generates it. However, if anyone wants the gory details in RAW, here they are:

4k image starts as 4096x2304 pixels at 12bit per pixel = 14,155,776 bytes.
Compression first does a lin to log curve to get it to 10bits, then applies REDCODE RAW compression. Resulting file was around 550k, I think. This gives about 25:1 compression, whereas in camera we'll use about 12:1 and also do some other magic to improve the quality of the compression. I'd take a rough guess to say that although in camera it will half as compressed, but will look even better still. File size of a frame in camera will be just over 1MB, but would look in comparison to the above frame to be the equivalent quality of about 1.5MB due to the improvements we'll be implementing in camera.

Hope that explains the scary math, but bottom line is: REDCODE RAW works, looks really good now, will look better in camera as higher data rate and more efficient encoding. I think you'll be happy with the results.

Graeme
 
I've made an impression that full sensor array is used for camera operator to see more than camera records to disk. And i believe that itll show full resolution image (4900x..) in viewfinder and lcd, just to help to deside composition and framing.

P.S. i aswell may be wrong
 
Awesome work, Graeme and RED.
Do you think at some point someone could post equivalent compression size on a more common format (h.264?) for comparison? I have trouble getting my head around how amazing this is.
Only thing I can see are some weird jaggies on eyes, edge of nose and edge of glass - is there anything else?
 
penfever said:
Do you think at some point someone could post equivalent compression size on a more common format (h.264?) for comparison?
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You can't really compare REDCODE and h.264 "like for like" as they are not alike. h.264 is a delivery codec and has interframe compression. This makes it aparently more efficient in terms of bit-rate, but makes it unsuitable for sourcing material to be edited. Multi-generation h.264 would fall apart pretty quickly, even if the first generation looked superficially 'good'. REDCODE is an intraframe (ie each frame is independently compressed) compression format.

penfever said:
Only thing I can see are some weird jaggies on eyes, edge of nose and edge of glass - is there anything else?
Click to expand...

I have to say I can't see any of the jaggies you are talking about. Are you viewing it "actual pixels" in Photoshop? It sounds like you may be viewing it in something which is (badly) scaling the image to a window.

Apologies if I'm telling you stuff you already know.

Nick
 
Oh my... This is unbelievable. I'm in shock. 100:1 compression?! You people in RED are insane. I love it.

I'm so happy I have a reservation!
 
Oh give me a break. I compared this picture with the original,
and IT'S NOT AS BIG! The 100x is achieved using CROPPING!
(in the original there is another woman, and a bus, and lots of
other stuff).

:)
 
I think he was being sarcastic... or at least I hope he was. You can never quite tell exactly what a smiley means at the end of a confusing post. :-P
 
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