AR0130 Datasheet, PDF (28/53 Pages) ON Semiconductor – CMOS Digital Image Sensor

AR0130: 1/3-Inch CMOS Digital Image Sensor
Features
Embedded Statistics
The embedded statistics contain frame identifiers and histogram information of the
image in the frame. This can be used by downstream auto-exposure algorithm blocks to
make decisions about exposure adjustment.
This histogram is divided into 244 bins with a bin spacing of 64 evenly spaced bins for
digital code values 0 to 2¹², 120 evenly spaced bins for values 2¹² to 2¹⁶, 60 evenly spaced
bins for values 2¹⁶ to 2²⁰.
The first pixel of each line in the embedded statistics is a tag value of 0x0B0. This signi-
fies that all subsequent statistics data is 10 bit data aligned to the MSB of the 12-bit pixel.
The figure below summarizes how the embedded statistics transmission looks like. It
should be noted that data, as shown in Figure 19, is aligned to the msb of each word:
Figure 19: Format of Embedded Statistics Output within a Frame
stats line 1
data_format_
code =8'h0B
#words =
10’h1EC
{2’b00, frame _{{2’b00, frame} {2’b00, frame {2’b00, frame histogram
_count MSB} _{_count LSB}} _ID MSB}
_ID LSB}
bin0 [19:10]
histogram
bin0 [9:0]
histogram _histogram
bin1 [19:10] _{bin1 [9:0]}
histogram
histogram
bin243 [19:10] bin243 [9:0]
8'h07
8'h07
stats line 2
data_format_
code =8'h0B
#words =
10’h1C
mean [ 19:10]
mean [9:0]
hist_begin
[19:10]
hist_begin
[9:10]
hist_end
[19:10]
hist_end
[9:10]
lowEndMean lowEndMean perc_lowEnd perc_lowEnd norm_abs_dev ^{lnorm_abs_dev}
[19:10]
[9:0]
[19:10]
[9:0]
[19:10]
[9:0]
8'h07
The statistics embedded in these rows are as follows:
Line 1:
• 0x0B0 - identifier
• Register 0x303A - frame_count
• Register 0x31D2 - frame ID
• Histogram data - histogram bins 0-243
Line 2:
• 0x0B0 (identifier)
• Mean
• Histogram Begin
• Histogram End
• Low End Histogram Mean
• Percentage of Pixels Below Low End Mean
• Normal Absolute Deviation
AR0130 DS Rev. L Pub. 6/15 EN
28
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