
2004 Apr 05
59
Philips Semiconductors
Product specification
XGA dual input flat panel controller
SAA6713H
7.11.3.3
Pixel measurement
For exact measurements within the incoming video
stream, two reference pixel positions can be defined with
ref_row_0, ref_col_0 and ref_row_1, ref_col_1. The
R, G and B components of this pixel are sampled and
available at ref_pixel_red_0/1, ref_pixel_green_0/1 and
ref_pixel_blue_0/1. The reference pixel colour values can
be used for fine tuning the external PLL in frequency and
phase and for colour gain adjustment.
Three submodes are available to output the maximum
value, the minimum value or the mean value at the
dedicated position (see Table 36).
To simplify the measurements, the values can be taken as
asinglesnapshotrepresentingthemomentaryvalueofthe
pixel at the reference position or they can be build up over
several frames, which is activated by programming the
number of frames to bits aa_cycles.
Table 36
Mode 10 (pixel measurement)
BIT
DESCRIPTION
Input values
aa_submode[1:0]
submode
00: maximum of pixel at dedicated positions
01: minimum of pixel at dedicated positions
10: mean value of pixel at dedicated positions
11: mean value of pixel at dedicated positions
measurement interval
00: 1 frame
01: 4 frames
10: 8 frames
11: 16 frames
pixel position 0 column
pixel position 0 row
pixel position 1 column
pixel position 1 row
aa_cycles[1:0]
ref_col_0[10:0]
ref_row_0[11:0]
ref_col_1[10:0]
ref_row_1[11:0]
Output values
ref_pixel_red_0[7:0]
ref_pixel_green_0[7:0] green channel colour value at position 0
ref_pixel_blue_0[7:0]
blue channel colour value at position 0
ref_pixel_red_1[7:0]
red channel colour value at position 1
ref_pixel_green_1[7:0] green channel colour value at position 1
ref_pixel_blue_1[7:0]
blue channel colour value at position 1
red channel colour value at position 0