Color Space Converter And Pixel Formatter - Matrox Radient eCL Series Installation And Hardware Reference

58 Chapter 4: Matrox Radient eCL hardware reference
I n
8 - b i t m o n o c h r o m e
1 6 - b i t m o n o c h r o m e
2 4 - b i t p a c k e d B G R
4 8 - b i t p a c k e d B G R

Color space converter and pixel formatter

The color space converter and pixel formatter can convert data being transferred
off-board as follows:
• Resizing. Image data can be cropped (ROI capture) and/or subsampled. This can
be useful to implement custom software-based motion detection because at a
reduced scale, image comparison is faster. The color space converter and pixel
formatter can subsample in the horizontal direction by integer factors of 1 to 16;
whereas, there is no restriction in the vertical direction; subsampling occurs using
nearest-neighbor interpolation.
• Flipping. Image data can be flipped vertically.
• Color space conversion. Image data can be converted as follows:
8 - b i t 1 6 - b i t
m o n o c h r o m e m o n o c h r o m e
y e s
y e s y e s
y e s
y e s y e s
The equations for the YUV16 conversion are described in the following table. The
value of depth is either 8 or 16 when converting BGR24 or BGR48 data,
respectively. Note that while performing BGR48-to-YUV color space conversion,
the operations are carried out on 16-bit data; then each resulting YUV component
is bit-shifted right by 8 bits ( >> (depth - 8) where the value of depth is 16).
C o l o r s p a c e c o n v e r s i o n
B G R - t o - Y U V
O u t
2 4 - b i t 3 2 - b i t 4 8 - b i t
p a c k e d p a c k e d p a c k e d
B G R B G R a B G R
y e s y e s
y e s y e s y e s
y e s y e s
y e s y e s y e s
E q u a t i o n s
• Y = ( 0 . 1 1 4 B + 0 . 5 8 7 G + 0 . 2 9 9 R ) > > ( d e p t h - 8 )
• U = ( 0 . 5 0 0 B - 0 . 3 3 1 G - 0 . 1 6 9 R + 2
• V = ( - 0 . 0 8 1 B - 0 . 4 1 9 G + 0 . 5 0 0 R + 2
1 6 - b i t 2 4 - b i t 4 8 - b i t
Y U V R G B R G B
( Y U Y V ) p l a n a r p l a n a r
y e s y e s
y e s y e s y e s
y e s y e s
y e s y e s y e s
( d e p t h - 1 )
) > > ( d e p t h - 8 )
( d e p t h - 1 )
) > > ( d e p t h - 8 )