MT9D015 Datasheet, PDF (57/75 Pages) ON Semiconductor – CMOS Digital Image Sensor

MT9D015: 1/5-Inch 2 Mp CMOS Digital Image Sensor
Sensor Core Digital Data Path
Fade-to-Gray Color Bars Test Pattern
In this test pattern, shown in Figure 24 on page 58, all pixel data is replaced by a Bayer
version of an 8-color, color-bar chart (white, yellow, cyan, green, magenta, red, blue, and
black). Each bar is 200 pixels wide and occupies 1024 rows of the output image. Each
color bar fades vertically from full intensity at the top of the image to 50 percent inten-
sity (mid-gray) on the 1024th row. Each color bar is divided into a left and a right half, in
which the left half fades smoothly and the right half fades in quantized steps every 8
pixels for a given color. Due to the Bayer pattern of the colors this means that the level
changes every 16 rows. The pattern repeats horizontally after 8 * 200 = 1600 pixels and
vertically after 1024 rows (using 10-bit data, the fade-to-gray pattern goes from 100 to 50
percent or from 0 to 50 percent for each color component, so only half of the 2¹⁰ states of
the 10-bit data are used. However, to get all of the gray levels, each state must be held for
two rows, hence the vertical size of 2¹⁰ / 2 * 2 = 1024). The image size is set by x_ad-
dr_start, x_addr_end, y_addr_start, and y_addr_end and may be affected by the setting
of x_output_size and y_output_size. The color-bar pattern starts at the column identi-
fied by x_addr_start. The number of colors that are visible in the output is dependent
upon x_addr_end – x_addr_start and the setting of x_output_size. The width of each
color-bar is fixed at 200 pixels.
The effect of setting horizontal_mirror or vertical_flip in conjunction with this test
pattern is that the order in which the colors are generated is reversed. The black bar
appears at the left side of the output image. Any pattern repeat occurs at the right side of
the output image regardless of the setting of horizontal_mirror.
The effect of subsampling and scaling of this test pattern is undefined.
MT9D015_DS Rev. M Pub. 4/15 EN
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