Overview
ISO 12640-1:1997 defines the standard for the prepress digital data exchange of CMYK standard colour image data (CMYK/SCID) within the graphic technology sector. Developed by ISO Technical Committee 130, this international standard provides a reliable framework for evaluating changes in image quality during essential prepress processes such as coding, image processing, data compression, storage, and transmission. The standard is widely recognized for its role in promoting consistent and objective evaluation of colour reproduction systems and workflows in graphic arts and related industries.
Key Topics
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Standard CMYK Colour Image Data: ISO 12640-1 specifies a set of carefully chosen standard colour test images, available in digital form, intended for use in research, development, product evaluation, and process control.
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Test Image Sets: The standard includes two sets of image data (primary and alternate), both in CMYK format:
- Natural images: Featuring diverse subject matter such as skin tones, highlights, shadows, fine detail, and challenging colours.
- Synthetic images: Including resolution charts and colour charts for evaluating image processing, printing sharpness, moiré, and aliasing effects.
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Image Data Characteristics:
- Data is supplied at two resolutions: 16 pixels/mm and 12 pixels/mm, corresponding to intended industry needs.
- TIFF/IT file format is used, ensuring compatibility with a wide range of imaging software and systems.
- Pixel interleaving and defined colour sequence (C, M, Y, K) allow systematic data handling.
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Global Application: The images are intended for use regardless of equipment type, supporting consistent evaluation processes across different sites and systems.
Applications
ISO 12640-1:1997 has broad value in prepress, printing, and digital imaging environments:
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System and Output Comparison: The standard’s reference images enable objective comparisons across printing systems, proofing devices, and colour copiers or facsimiles, supporting quality control and troubleshooting.
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Image Processing Evaluation: By monitoring reference images before and after various processing stages, users can assess the effects of image enhancement, transformation, and compression algorithms.
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Process Control and Calibration: The standard assists in the characterization and calibration of digital workflows, helping maintain accurate colour reproduction and minimizing variability between equipment.
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Research and Development: Manufacturers, software developers, and academic institutions utilize these test images in performance benchmarking, process optimization, and new technology validation.
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Industry Collaboration: The standard facilitates collaboration by ensuring all parties evaluate results using identical reference data, eliminating subjective interpretation due to image content or origin.
Related Standards
Relevant ISO standards and references associated with ISO 12640-1:1997 include:
- ISO 9660: Volume and file structure of CD-ROM for information interchange, related to the distribution format of test images.
- ISO/IEC 10149: Data interchange on read-only 120 mm optical data disks, underpinning the physical medium requirements.
- ISO 12639: Tag image file format for image technology (TIFF/IT), specifying file format compatibility.
- ISO 12642: Input data for characterization of 4-colour process printing, complementing the use of standard colour targets.
- ISO 14672: Statistics of SCID images, providing further analysis and characterization of test image data.
Keywords: ISO 12640-1, CMYK standard colour image data, prepress digital data exchange, graphic technology, printing, image quality evaluation, TIFF/IT file format, standard test images, colour reproduction, process control.
Open preview (PDF)Graphic technology — Prepress digital data exchange — Part 1: CMYK standard colour image data (CMYK/SCID)