Canon N650U - Manual (Page 63)

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Scan Mode
Any one of the various methods used to reproduce image data. Scan modes are
distinguished by the number of bits used to describe each pixel. Plug-in Module
CS-U features the following scan modes.
• Color (Photos)/Color (Documents): assigns 8 bits of data for each color
channel (RGB) in each pixel. Each pixel is therefore assigned 24 bits.
• Grayscale: assigns 8 bits of data to its single color channel. Each pixel is
therefore assigned 8 bits.
• Black and White: assigns 1 bit of data to each pixel.
Scanning
The process of using a scanner to read image data. Scanned data is sent to the
computer as image data.
Shadows
The darkest portions of an image scanned in a color or grayscale image mode.
Threshold Value
The dividing value at which a pixel is determined to be either black or white
when the image is reproduced as a black and white image. The higher the
threshold, the darker the image. The lower the threshold, the brighter the
image.
Tone Curve
A function used to adjust image brightness. The tone curve (or gamma curve) is
a graphic representation of the relationship of the input from the scanner to the
output to the monitor or printer.
Unsharp Mask
A function that sharpens image outlines. Makes an image appear naturally
sharper without changing the brightness, contrast or color balance.
White Eyedropper Tool
Tool used to the select the brightest portion of an image in the preview area.
Used with the Histogram function to adjust image brightness. When this tool is
clicked on the image, all areas that are brighter are set to pure white.