C2R Colibri 5 Series, Руководство пользователя

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Colibri serie 5 : User’s guide
© 2000-2008 C2R Technologie, Sarl. All rights reserved.
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Rev. C
Intelligent Signature Capture - IMGBOX
IMGBOX commands can only be used with PDF417, Code 39, Code 128, Aztec, Codabar, and
Interleaved 2 of 5 symbologies.
Intelligent signature capture ships only part of an image to the host application. This method
reduces transfer time and file size, while simplifying signature capture.
Below is an example of an intelligent signature capture application. In this example, the operator
reads the bar code, which is then transmitted to the host application. Upon the receipt of the bar
code data, the host application sends the IMGBOX command, which tells the scanner to output
only the area of the image corresponding to the signature capture box. The scanner also
automatically adjusts for aspect ratio and distortion, issues that arise due to scanner skew with
respect to the bar code.
Align the aimers with the signature area (not with the bar code), then activate the trigger. Send the
IMGBOX command string after the trigger command.
An important aspect of intelligent signature capture is that all dimensions used in the application
are measured as multiples of the minimum element size of the bar code. Using this method,
intelligent signature capture always outputs the correct image size and resolution, no matter the
distance at which the scanner is held from the bar code, assuming that the entire signature
capture area is within the scanner‟s field of view.
The intelligent signature capture command string for this application is:
IMGBOX40S0X70Y190W100H1R0F
IMGBOX Modifiers
D - Pixel Depth: Indicates the number of bits per pixel in the transmitted image.

8D 8 bits per pixel, grayscale image

1D 1 bit per pixel, black and white image
F - File Format: Indicates the type of file format in which to save the image.

0F
KIM format

1F
TIFF binary

2F
TIFF binary group 4, compressed

3F
TIFF grayscale

4F
Uncompressed Binary

5F
Uncompressed grayscale

6F
JPEG image (default)

7F
Outlined image

8F BMP format
H - Height of Signature Capture Area: In the example, the height of the area to be captured is 1
inch, resulting in a value of H = 1/0.01 = 100. The value for H is slightly larger, to accommodate
some extra image capture area outside of the signature capture box.
K - Gamma Correction: Gamma measures the brightness of midtone values produced by the
image. You can brighten or darken an image using gamma correction. A higher gamma correction