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Old Apr 17, 2003, 6:22 PM   #21
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Last week i stated in an above post:

"*Unless some non-lossy compression format is used internally that the processor can handle at high enough speeds, then the total buffer capacity would have to be approx. 96mb to hold 5x 17-18mb 6mp RGB 24 bit files. "

It would appear that this, or a similar phenomena is the case. At the moment, Jkirk has only been able to find 1 x 8megabyte chip and 2 x 16megabyte chips. But, considering tht fuji claims 12 bit A/D rather then the 8bit i was 'wrongly' assuming since the files outputed are only 8bit(24bit composite) then this is even more odd then ever so far.

http://forums.dpreview.com/forums/re...essage=4892516

-Chris
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Old Apr 18, 2003, 4:32 AM   #22
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Quote:
It would appear that this, or a similar phenomena is the case. At the moment, Jkirk has only been able to find 1 x 8megabyte chip and 2 x 16megabyte chips. But, considering tht fuji claims 12 bit A/D rather then the 8bit i was 'wrongly' assuming since the files outputed are only 8bit(24bit composite) then this is even more odd then ever so far.
Dont forget about the scratchpad memory! Unlike a Foveon CCD which can capture all three colors at every photosites. Most CCDs are black and white and will convert the incoming light through three Red, Green and Blue CFA filter array, regardless if it's square or diagonal (or complementary color instead). The camera must then hold this intermediate 12-bit of individual R, G, and B values after the A/D (the output of the CCD is serial), before it can interpolate this to either 3 or 6Mp image of (256,256,256) color. Everyone must also realize that any arithmetic operation will also automatically double the number of bits in any intermediate file (before round-off)! So in reality not all that memories can be assumed as 'buffer' to hold pictures, but are required by the camera as scratchpad to run its foreground/background tasks.

Most cameras would have two memory banks: one for the custom ASIC, and one for the processor all working in concert to one another to increase the camera speed... Chips counts (or sizes) are not everything. The s602 may compute the final picture on the fly for all we know, or can it be infer by the long write time to the flash cards (The D7i does it in 8s)? A better approach would have been for the camera to provide the raw picture which is still 12-bit, instead of tiff (8-bit only) and the resulting files would even be more compact, saving all that memory space as well as shortening the writes time! ops:
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Old Apr 18, 2003, 9:49 AM   #23
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Everyone must also realize that any arithmetic operation will also automatically double the number of bits in any intermediate file (before round-off)! So in reality not all that memories can be assumed as 'buffer' to hold pictures, but are required by the camera as scratchpad to run its foreground/background tasks.

The itemized totals whch jkirk has been able to locate so far(which are specified in the link i provided):

Flash - 2MB Ext + 512-768KB Internal
RAM - 40MB External + 40KB Internal

-Chris
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Old Apr 19, 2003, 12:25 AM   #24
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I thought I felt my ears burning :-)
The Buffer issue has been perfectly analysed and wrapped up.
3.1Meg of 16 bit data is Flushed directly to primary Buffer. Since the A/D is 10/12 bit that leaves Hardware 4/6 bits free to add the ISO (gain) to the Top bits, b15-b14. The ISO bits are crutial to give the final value, and because they are added (by weight) in hardware, there is NO MIPS loss. This is a standard tequnique we use in Strain guage. Doing the maths, MIPS available by the M32R, Fuji could have actually given us 30fps in RAW without sweat (100 MIPS), but post processing would have been a KILLER :-). They DO move that rate in movie mode. The Primary Buffer is now pretty much full. From here on, ALL proessing is done "on the fly", as we can see by the different "freeze times". The Secondary Buffer holds 118KB for the LCD / EVF, Video Frames, CF or SM cache, USB cache etc. ALL algorithm conversions are done in the INTERNAL Buffer, 40KB x 32bits wide, up to 400MHZ peak w/pipeline. It is an excellent design and the reason we have such incredible speeds.
I only wish they went 1 STEP further ... Just losslessy compressed the RAW data, say to 3MB at a cost of 10-20% MIPS overhead (=peanuts), and forgot all about stupid TIFF or JPG. Imagine the option of 30fps RAW piped straight down a USB2 line .. droooool.
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Old Apr 19, 2003, 4:09 AM   #25
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There's more MIPS in common with both cameras than anyone thought! :lol: :lol: :lol:
http://forums.dpreview.com/forums/re...essage=3283322

... and the Minolta folks are drooling too!
http://forums.dpreview.com/forums/re...essage=4590524

Also don't forget theses tiny things run on batteries so the more one ups the MHz, or makes them to be a Cray, the less power there's is left for the pictures... Theses cameras run on 4 AA's, and not a 500W AC powered PSU! ops: ops: ops:
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