Re: C3088 CMOS Imaging Sensor Questions

"Meindert Sprang" <ms@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
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<weg22@xxxxxxxxxx> wrote in message
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Can you please explain why you need two buffers when doing image
processing (I'm new at this)? My PIC has 3.94 KB of RAM and I probably
won't be processing the entire image...more like a 100 x 292 image.

Ehhm, 100 x 292 is 29kbytes. How is that going to fit into 3.94kbytes?

Regarding the sampling: I have used a Motorola DSP (DSP56303) to sample a
5MHz pixel rate, using an interrupt handler written in assembly that only
read one line at a time. This DSP ran at 80MHz. I very much doubt that a
PIC
would be able to do the same, especially when programmed in C....

Meindert

I don't know if it will easily interface to your PIC, but I used a IDT 7205
FIFO to capture sub-windowed images from a camera. Once a sub-frame is in
the FIFO, you can read it out non-destructively for multiple passes at the
data. Gruesome, but better than nothing. I was using an AtMega64 at the
time. If you can afford the princely sum of, of, $10 or $20, you could get a
real processor with DMA and an address space that could eat the whole image.
You still need some serious horsepower to do anything with it at 5 fps.

BTW: can't a PIC read an entire port as one byte? Why did you think you
needed code like this?

image[row][col] = Y7*128+Y6*64+Y5*32+Y4*16+Y3*8+Y2*4+Y1*2+Y0;

instead of

imagePtr++ = PORTY;

Bob



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