I did a Systran.com translation of part of this article (credit to tke918 for posting the link). There is some info that gives me hope for the C3000, if the translation proves to be correct. I will not comment on the article, though, because even where I can decipher the translation, I only have a vauge understanding of the technical information.
(PXA270 Graphics Capabilities)
As for main CPU, PXA270 of Intel. The clock is 416MHz. Function of wireless MMX and the like is added in comparison with PXA255, accumulates also the various peripheral circuits as the one for PDA device. This time there is no ATI W100, but the LCD controller of PXA270 built-in is utilized in regard to indication. In addition, the function and the like where W100 processed until recently in the type seems that is actualized with the software entirely.
The LCD controller of PXA270 corresponds to the largest 800×600 dot, those whose two graphic overlays are possible. When there is an overlay display function, playback processing of the animated picture data becomes simple. Because it should have kept writing the animated picture frame data to the overlay private memory territory animated picture playback application - without considering Shaun's itself indicatory and display position and the like. In addition, in the overlay indication of PXA270, YCbCr which is used with JPEG and MPEG not only RGB type (brightness and color difference) indication being possible even with type, it is not necessary to do color spatial conversion at the time of indication. The frame buffer is taken into memory, uses DMA and to LCD has reached the point where output is done.
The LCD controller of PXA250/255 which was used with SL-C700 - 860, is thought that display function of the simple frame buffer furthermore the device like ATI W100 in the shelf damaging and indication of the multimedia data was necessary. Vis-a-vis this, the LCD controller of PXA270 function becomes high, in addition, because there is also wireless MMX order and the like the external graphic controller unnecessary. In addition, it meaning that the device decreases, it is possible that much to decrease electric power consumption.
Thoughts, anyone?
Hi ZeeUser,
The ATI W100 in current Zauri does more ore less two things
* Color Space Transformation
* Video Overlay / HW Scaling
Color Space Transformation :
If you would have to describe an Image, you could save for every Pixel the amount of Red, Green and Blue that is needed to get its color. Such a Color Space is called RGB and you need 3 values per pixel. This is basically a *.BMP image
In video coding another way of describing an image is common: YCrCb
There you have aswell 3 values per pixel (Y = "luminance", intensity of a B&W image, Cr = "Chrominance Red", how much more red than green, Cb = "Chrominance Blue" - How much more blue than green)
You still have 3 values per pixel, But the eye is less sensitive to Color Difference that to light intensity, so it is possible to compress color difference more agressively
This would correspond to a *.jpg with maximum quality setting.
Now the problem is when you want to play back a video that was coded using YCrCb (like MPEG/divx) you will have to convert it back to RGB at some point, because the LCD works internally in RGB. In 700 Series this was done by ATI W100 because the PXA255 had no hardware converter and not enough computing power to do it in software alone. If you take a look at figure 7-1 of Intels PXA27X spec's you will find that PXA27X includes a hardware based Color Space transformer in its internal LCD controller.
Video Overlay / Scaling:
If you want your video (which uses YCrCb) in a window ontop of your desktop which uses RGB, you need a way to Mix Color Spaces . This is what the Overlay is for. It lays the video image over the normal one. PXA27X has actually *two* overlay units.
Then there is the scaler, which basically scales your video from its resolution to the reolution of the LCD (otherwise it would not be possible to to fullscreen video) This had to be done by ATI W100 in current Zauri, because PXA255 is not fast enough. But with Wireless MMX, this has changed.
IMHO this is a good thing:
* PXA27X is fully documented unlike the W100
* yon dont have an additional chip to buy, and
* you save power. SL-C7XX series uses W100 but PXA's internal controller is still there and consumes power doing nothing.
Over all Sharp had to put a W100 on the side of PXA255 because it was not yet up to the job. But PXA27X has grown and can stand on its own feet, so no need for W100 anymore.
tom
PS: I think, the mplayer which needs W100 will not work with C3000.
You need to wait until somebody adapts mplayer for PXA27X.
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