Technology / Imaging

LEADTOOLS Signed Image Support

Image Processing: Signed Image Data Support

Image (bitmap) data values may be expressed as absolute value-only, or as positive/negative integer values ("signed" images). These image values are stored in a look-up table (LUT), where the image data range is represented as a single series of (positive) integer values.

Most LEADTOOLS image functions now support both signed (+/– integer) and unsigned images. Where signed images are supported, LEADTOOLS can manipulate either the LUT values, or the image data directly. When displaying images, mapping the negative and positive values of the signed images to LUT values speeds up processing.

Who uses signed images?

Signed images are most commonly used by medical imaging applications supporting the DICOM standard. Astronomical and geophysical image data may also be signed.

When and why do signed image values matter?

Signed image data is often used when image classification is based on variation from a reference value. For example, image values for DICOM images acquired from a Modality depend on a reference plate, with some (positive) values recorded above the plate threshold, and some (negative) below. Some astronomical images are also signed as variations from a nominal background reference value.

When would I want to manipulate the LUT, and when would I want to manipulate the image data directly?

For many effects, the final result will be the same whether you apply the effect on the LUT or the source data—but processing the LUT will be much faster. For example, inverting the start and end colors of the LUT is faster than inverting the intensity value of each pixel.

Other LEADTOOLS SDK Technologies Related to Document Image Processing

LEADTOOLS SDK Products that Include Document Image Processing

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LEADTOOLS Imaging Pro SDK

LEADTOOLS Imaging Pro includes the tools developers need to add powerful imaging technology to applications. With more than 20 years of imaging development expertise, LEADTOOLS Imaging Pro includes display functions and controls, image compression, image processing, TWAIN and WIA scanning, color conversion, 200+ display effects, 150+ image formats, printing, database imaging, imaging common dialogs and screen capture.

LEADTOOLS Document Imaging SDK

Develop powerful document imaging applications with LEADTOOLS Document Imaging. Features include comprehensive image annotation, specialized bitonal image display such as scale-to-gray and favor-black, and specialized bitonal image processing. Other features include performance and memory optimizations for bitonal images, document image clean-up including inverted text, border, hole-punch and line removal, and scanning with LEADTOOLS Fast TWAIN and WIA.

LEADTOOLS Recognition Imaging SDK

The LEADTOOLS Recognition Imaging SDK is a handpicked collection of LEADTOOLS SDK features designed to build end-to-end document imaging applications as part of an enterprise level document automation solution that requires scanning, OCR, OMR, forms recognition and processing, archival, annotation and display functionality. This powerful set of tools utilizes LEAD's industry LEADing image processing technology to intelligently identify document features that can be used to recognize any type of scanned or faxed form image.

LEADTOOLS Document Imaging Suite SDK

The LEADTOOLS Document Imaging Suite SDK is a comprehensive collection of LEADTOOLS SDK features designed to build end-to-end document imaging applications within enterprise level document automation solutions that requires capture, OCR, OMR, forms recognition and processing, PDF, print capture, archival, annotation and display functionality. This powerful set of tools utilizes LEAD's industry LEADing image processing technology to intelligently identify document features that can be used to recognize any type of scanned or faxed form image.

LEADTOOLS Medical Imaging SDK

Develop powerful Medical Imaging applications with the LEADTOOLS Medical Imaging SDK. Features include comprehensive full DICOM dataset support, 8-16 bit extended grayscale image support, image annotation, specialized extended grayscale image display such as window level and LUT processing, and specialized medical image processing. Other features include lossless JPEG compression, and signed and unsigned image data processing.

LEADTOOLS PACS Imaging SDK

Develop robust PACS Imaging applications with LEADTOOLS PACS Imaging. Features include Medical Web Viewer Framework, high and low level PACS SCP and SCU functions and controls, secure PACS communication, comprehensive DICOM data set support, image annotation, extended grayscale image display such as window level and LUT processing, and specialized medical image processing. Other features include lossless JPEG compression, JPIP and signed and unsigned image data processing.

LEADTOOLS Medical Imaging Suite SDK

Develop powerful PACS and Medical imaging applications with LEADTOOLS Medical Imaging Suite. Features include Medical Web Viewer Framework, Medical 3D, Zero Footprint HTML5 DICOM Viewer, DICOM Multimedia codecs, high and low level PACS SCP and SCU functions and controls, secure PACS communication, Print to PACS, comprehensive DICOM data set support, image annotation, extended grayscale image display such as window level and LUT processing, and specialized medical image processing. Other features include lossless JPEG compression, JPIP, and signed and unsigned image data processing.

LEADTOOLS Multimedia Suite SDK

The Multimedia Suite SDK is a comprehensive collection of multimedia development technology from LEAD Technologies. By bundling features from the Multimedia SDK, DVD Module, Video Streaming Module, MPEG-2 Transport Module, Imaging Pro SDK and Distributed Computing SDK, the Multimedia Suite provides everything a developer needs to create enterprise level multimedia applications for a wide variety of industries including defense, broadcast, security and more.

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