Motorola DS4800 Series, Руководство по продукции

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Intelligent Document Capture 7 - 3
The IDC Maximum Rotation parameter controls the maximum rotation any edge of the form can have in
relation to the imager's horizontal or vertical axis.
IDC Operating Mode = Free-Form or Linked
The document capture region is a rectangular piece of paper, or a portion of it enclosed by a rectangular
border. In either case, all four sides of the capture region must be completely within the engine's field-of-view,
and there must be sufficient contrast at the border of the capture region. For example, if a piece of white paper
contains the document to capture, it must be put in front of a dark background.
By default, the engine captures the largest rectangular region within the field-of-view. To specify a particular
border type, use the
IDC Border Type parameter.
The region must contain at least 10% of the field-of-view in two dimensions.
If an IDC bar code is decoded, its location is used to start the search for the capture region. Otherwise, the
capture region is searched from the center of the field-of-view. IDC also uses the orientation of a decoded IDC
bar code to orient the output image.
Image Post Processing
After determining the document capture region, the firmware de-skews and re-samples the region as described
below. Enabling
IDC Captured Image Brighten calls normalization, where the brightness of the image is made
uniform, and contrast is enhanced as a large percent of background pixels is made completely white (a smaller
percent of pixels is made completely black if the firmware determines there is no danger of enhancing the
contrast of a very bland area). Enabling
IDC Captured Image Sharpen enhances the sharpness of the image.
The image is re-sampled about one output pixel per input pixel for Free-Form or Linked modes and two
pixels-per-module in Anchored mode.
The image is compressed and transmitted in one of the standard image formats selected by the IDC File
Format Selector , IDC Bits Per Pixel , and IDC JPEG Quality parameters.
Note that it may take several seconds for post processing to complete, depending on the size of the captured
region, the options enabled, and the decoder model.
Data Transmission
After processing the captured image, it is assembled with the decoded bar code data (if applicable) into an
ISO/IEC 15434 style packet and transmitted to the host. The decoder issues the standard decode beep and
the trigger can be released. Be sure the
USB Device Type on page 3-4 is set to Symbol Native API (SNAPI)
with Imaging Interface .
PC Application and Programming Support
For a sample application running on the Microsoft Windows operating system, contact your Motorola Solutions
representative. This application displays bar code data and/or captured images from Intelligent Document
Capture enabled decoders and allows setting and reading IDC parameters. Complete source code and
documentation are also provided for developing custom applications. The application includes documentation
for the ISO/IEC 15434 format as used by the IDC firmware and C# code to process it.