Datasheet

PDF: 09005aef8202ec2e/Source: 09005aef8202ebf7 Micron Technology, Inc., reserves the right to change products or specifications without notice.
MT9D111__7_REV5.fm - Rev. B 2/06 EN
156 ©2004 Micron Technology, Inc. All rights reserved.
MT9D111 - 1/3.2-Inch 2-Megapixel SOC Digital Image Sensor
Start-Up and Usage
Micron Confidential and Proprietary
Figure 37: Tonal Mapping
The contrast settings on the MT9D111 are implemented by applying an S-Curve func-
tion on to the data points of the gamma curve. These resulting points then replace the
existing gamma curve points, and the image is processed using this new contrast-
enhanced gamma curve. Identical S-curve is applied to all three RGB components.
The S-curve is created by joining a linear midsection (often with a slope greater than
one) to curved sections for highlights and shadows. The following constraints apply to
the overall curve to ensure a smooth curve appropriate for increased contrast:
1. The first/lowest point must be (0,0) and the last/highest point must be (1,1) (normal-
ized).
2. The midsection and each of the end-curves must intersect on the same points.
3. The slope of the midsection and each of the end-curves must be equal at the intersec-
tion points.
The midsections a simple linear function of the form: y = mx + b. Each of the end-curves
(shadow and highlights) must be a trinomial to satisfy all boundary conditions.
Figure 38: Contrast Diagram
x
1
x
2
y
1
y
2
x
1
x
2
Dark Mid Bright
Dark Mid Bright
Input
Input
OutputOutput
Dark Mid Bright
y
2
y
1
Contrast Only
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
Highlight
Region
Linear Mid
Tone Region
Shadow
Region
(x
1
,y
1
)
(x
2
,y
2
)