4:4:4 12-bit Uncompressed DVX100

[Mark Grgurev]

<<<-- Originally posted by Thomas Smet : The DVX already uses the pixel shift so you cannot use it again. Juan has shown us some images captured however that were blown up to 2k images and they look damn good. A program such as s-spline pro can make it even better. I however have used just Photoshop and even went up to a 4k image size with it still looking pretty damn good although a hair soft. Just having raw RGB pixels alone make the blowups look very good. It is sort of like if you have a 2 megapixel digital camera and it says you can get 8x10 photos from it. Well those 8x10 photos would be less than 150 dpi which isn't as good as getting a 4 x 6 at 300 dpi. However because digital cameras use RGB pixels the blowup looks much better that if you were to try and do it with a video frame. Juan's mod is basically allowing us to turn the DVX into a 1 megapixel digital camera that shoots 24 frames per second at perfect raw RGB.

So to answer your question you can blow up the footage to be 1920 x 1080 HD rez and it will look great except for a slight softness compared to actual HD footage. Some may actually like this softness because it makes the footage seem a little more film like instead of HD like. -->>>

So, your basicly saying that when a camcorder like, lets say, an XL1s uses pixel-shift it then uprezzes it to 720x480. that doesn't quite make sense to me. But then again I never quite understood how shifting the green CCd 1/2 a pixel to the right thus increasing its sampling points would allow a CCd with 270,000 pixels to provide a DV image. If anything I kind of assumed pixel shift would sort of work as and uprezzing thing.

[Juan P. Pertierra]

Phil&Mark

Phil:
You can always use the anamorphic adapter, which is what I am using. Since you can get the full width of the CCD, you actually get a ~1.83 ratio out of it.

I am working hard on re-designing the box and choosing the production circuitry such that both the box and mini35 can be mounted at the same time.

Does anyone have a picture of the ~bottom~ of the DVX with the mini35 on it?

Mark:
The best way I can explain pixel shift, is by looking at how single CCD color cameras work. Each pixel sensor has a color filter on it, such that the raw image is not a black and white image with absolute brightness(Y) for each pixel, but rather a mosaic of colors, with the magnitude of a specific color content for each pixel. Adjacent pixels of different colors can then be used to approximate the color of that pixel.

To the best of my knowledge, pixel shift is this same idea but with 3 CCD's...by simply offsetting CCD's slightly from each other, you can have a pixel element of, say, the green channel capturing a detail which lies in a element division of the other CCD's. The data can be combined into a larger image, with better detail, although as you might expect the color rendition is slightly affected because technically each element of each sensor doesn't capture the exact same detail color.

Now that I lay it out like this, it would be interesting to somehow have an up-rez program like S-Spline take 3 RAW RGB layers and take CCD shift into consideration. What i've been doing so far is aligning the layers, but if there is indeed intentional CCD shift in the DVX, that info can be used to create ~even better~ HD images.

Juan

[Phil Rhodes]

Hi,

Please excuse the repetition, but I'd like to ask again what you are doing about a filesystem on the hard disk recorder. Does your device comprise a microprocessor system running a full-blown operating system or have you implemented a common filesystem in firmware? I would be impressed if you had!

Phil

[Juan P. Pertierra]

I'm using FAT32, in configurable logic.

[Phil Rhodes]

Hi,

I am duly impressed.

- Phil

[Emmanuel Cambier]

Hi Juan
Mini 35 compatibility really is a must I think.
It's well worth the hard work it's putting on you, and I am sure many
will bless you if you succeed.
Can't wait
Take care
Emmanuel

[Juan P. Pertierra]

Well, i've done some significant changes, and the box should now fit snuggly behind the mini35 adapter. I haven't played with a mini35, but I'm assuming that using the tripod mount is out of the question, since any vertical offset may cause the mini35 to not align properly with the lens? Does this make sense?

I'm going to have to figure out some other way of attaching it to the bottom of the DVX.

Juan

[Charles Papert]

Yes it does--did you get the picture of the Mini35 setup I sent you Juan? So, just curious--by "behind" the adaptor, what does this mean exactly?

[Juan P. Pertierra]

Charles:

Yes, i received the picture and it was very helpful, sorry i didn't get back to you.

If you look at the original box in the picture i posted, and imagine splitting the box in half along the length of the camera, the new box occupies what would be the rear half, slightly behind the tripod mount.

Juan

[Wayne Morellini]

Out of curiosity, I've started a discussion thread:

4:4:4 Uncompressed 1080i HDR-FX1?

[Chris Rubin]

I was playing around with edge enhancement on samples Juan has posted so far and I have to say, this stuff has got some juice in it! The uncompressed images can literally be sharpened into oblivion after uprezzing and they still look great. I posted a sample of Juan's cat for your viewing pleasure here:

http://www.hot.ee/whiteroom/sharpening_comparison.psd

This is a 3-layer .psd file. I uprezzed the original image to hi-def, but cropped it in the end to keep the file smaller. Comparison to original size included. Mind you, this is an old example, so pay no attention to the speckles. You know they'll be gone in the final version.

Cheers,
Chris

[Juan P. Pertierra]

I don't remember if I posted this or not:

http://web.ics.purdue.edu/~pertierr/cap11_HD.tif

I showed it to a senior proffessor who does a lot of 4k graphics and HD work. he was very impressed with it, he couldn't beleive it came from a DVX100. He has a macbeth chart and is interested in doing some proper green screen tests in the next few weeks.

There have been several changes, but we are now ready to assemble a final production version of the device. We've done our best to keep costs down for the initial version. Some features such as SDI are a bit costy to implement, so if there is a great demand for it, we will provide a new version or add-on module.

The final design uses USB2.0 instead of Firewire800. It will still work directly to a drive, but USB2.0 allows for a smaller device(and thus compatibility with the Mini35), and it also allows for the use of a firewire800 drive when hooked up to a laptop. Before, the firewire800 port would be occupied with the device. it makes more sense to use USB2.0 because it has enough bandwidth to handle the full quality data. Drivers will be provided so you can use your laptop as a preview screen while you record. The device also has a VGA output port so it can be hooked to any screen which supports 800x600 72Hz. We are using a tiny flat panel from a POS system.

Juan

[Gary McClurg]

so when can we see the web site.

[Wayne Morellini]

Out of curiosity Juan, what is the maxium resolution you are getting from the DVX100?

[Juan P. Pertierra]

773x494 pixels per frame, 36-bits of color information per pixel.