Instruction manual

Description of the data path
8.15 Color interpolation and correction
The color sensors capture the color information via so called primary color (R-G-B) filters placed
over the individual pixels in a ”BAYER mosaic” layout. An effective Bayer -> RGB color
color version cameras. Before converting to the
Color processing can be bypassed by using the so called RAW image transfe
RAW-mode is primarily used to
 save bandwidths on the IEEE-1394 bus
 achieve higher frame rates
 use different BAYER demosaicing algorithms on the PC
RAW-mode is accessible via Format_7 Mode_1.
 If the PC does not perform BAYER to RGB post-processing the b/w image will be
superimposed with a checkerboard pattern.
8.15.1 Color interpolation (BAYER demosaicing)
i d for each pixel. Only two lines are
needed for this interpolation:
interpolation already takes place in all Marlin
YUV format, color correction is done after Bayer demosaicing.
r.
In color interpolation a red, green or blue value s determine
R1 G1 R2 G2
G3
B1
G4 B2
P1
P2 P3
Input:
Output:
Figure 53: Bayer demosaicing (interpolation)
11
2
31
G
+
1
11
BP
G
P
RP
blue
green
red
=
=
=
12
BP
blue
=
2
4
2
22
G
P
RP
green
=
=
1
G
red
+
2B=3
2
4
3
23
P
P
RP
blue
green
red
=
2 GG +
=
Please or camera, a black ne p left and
right image borders. This is also a consequence of BAYER demosaicing as the image width
displayed on the color camera is
not
 note that on the col border o ixel wide forms on the
scaled down.
MARLIN Technical Manua
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