Ccd Blemish Detection And Compensation; Ccd Blemish Detection Method Types - Sony SS-HQ1 Application Notes

- SS-HQ1 Application Notes -
Ver.1.0.0 January 7, 2005

11.2. CCD blemish detection and compensation

Blemish specifications are established for spot blemishes, which are a type of pixel defect. During the
production process, Sony CCDs are sorted based on these blemish specifications. However, white blemishes,
in which the blemish level varies in proportion to the temperature, may be observed during use, especially at
high temperatures, due to external factors and the like. The CCD blemish detection and compensation function
automatically detects and corrects such white blemishes, so that high image quality can be maintained.
The SS-HQ1 automatically detects and corrects blemishes in order of blemish level (starting with the highest
blemish level). It can detect and correct 32 blemishes.

11.2.1. CCD blemish detection method types

Static blemish detection (Static detection)
A blemish is recognized by static detection, when a target pixel is more than a fixed level to a black level, while
the CCD is shielded from light.
Dynamic blemish detection (Dynamic detection)
A blemish is recognized by dynamic detection, when a target pixel is more than a fixed level to the surrounding
pixels, during the normal imaging state.
Dynamic detection does not need to shade CCD like Static detection.
However, Since Dynamic detection detects in the normal imaging state, it may incorrect-detect a place without
a defect.
Manual detection
The SS-HQ1 detects and corrects blemishes automatically, so manual blemish detection is not supported.
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