Re: OV7620 RGB demosaicing problem



On Oct 5, 7:52 pm, "ksanthos" <taskin.balt...@xxxxxxxxx> wrote:
Hello,

I'm working on an imaging system which uses C3188A digital cmos
camera(contains OV7620 image sensor). It is controlled by a PIC18F452 and
each frame I want to view is stored in a FIFO buffer, AL422B. I can store
a frame and transfer it to my PC by RS232. However I have a problem with
the images, they look gray scale although they should be RGB.
I have configured OV7620 to transmit QVGA images in progressive mode. I
haven't changed the data mode, it's repetitive because one-line output
format is not supported in qvga mode. The camera is configured to output
raw data also.
Anyway, when I display the bayer pattern in bmp format, I see that color
sensors do not seem to work properly. I display each pixel as below:
The bayer pattern form is:
B G B G
G R G R
bmp file form is:
(0, 0, B), (0, G, 0), (0, 0, B), (0, G, 0)
(0, G, 0), (R, 0, 0), (0, G, 0), (R, 0, 0)
This is just for test purposes. I want to see red things red, blue things
blue and green things green however the sensor doesn't seem to sense them
in that way, they all look the same color which is greenish. I have also
converted bayer pattern into RGB and saw that the image is completely gray
scale although the sensor is configured for raw data output(it looks like
that each components digital value is so close to each other that when 3
components are combined it gives a gray scale pixel). Because the image is
QVGA and it is outputted in repetitive format 2 bytes are sent for each
pixel, am I right? So, I should be receiving 153600 pixels(320 x 240 x 2)
and this is exactly what I count during the transfer. So there shouldn't
be any pixel missing issue. Moreover the camera is connected to the FIFO
memory directly so they synchronize each other by hardware therefore there
shouldn't be any problems caused by software. Other than that I couldn't
find any way to resolve that issue, could anybody help me in that
problem??

Thanks!!

Taskin Baltaci

Seems inappropriate register setting to me, have you signed NDA with
OV? If not then i don't think you would be able to get very details.


Just a wild guess,
ali

.