Overview
ISO 20616-1:2021 - Print requirements eXchange (PRX) - defines an extensible XML 1.0 file format for exchanging print quality requirements and associated metadata. Designed by ISO/TC 130, PRX enables one-way digital transmission of a print buyer’s quality expectations (references, tolerances, scoring/grading rules and calculation formulas) to print quality control applications and print quality management systems. It is explicitly not intended for automating the loading of job orders or directly populating service provider production systems.
Key topics and technical requirements
- XML-based schema: Conforms with W3C XML 1.0; an official XML schema (ISO20616-1prx.xsd) is provided (Annex A).
- Extensibility: Support for TagCollection and CustomResources to allow vendor‑ or customer‑specific metadata without breaking interoperability.
- CxF integration: References ISO 17972‑3 (CxF/X‑3) for colour target and output target data; elements exist to employ CxF reference data.
- PRX quality specification model: Structured elements such as PRX, PRXInfo, BuyerInfo, EvaluationInfo, GradingInfo, GradingScale, Grade, ValueRange, ZeroBaseline and BasisOfCalculation define how buyers express quality expectations.
- Scoring, weighting and grading: Elements for ScoreWeightingFactor, GradeWeightingFactor and CalculationVariable let buyers define mathematical formulas for assessment.
- Sampling and evidence: SamplingPosition, SamplingPositionImageData, PositionLocationImage and SamplingPositionMatrix support where and how measurements/images relate to quality checks.
- Quality aspects covered: Color, registration, defects, barcodes, customer job/item metadata and compliance goals are supported.
- Supporting materials: Annex C contains samples; electronic files and examples (parsable .prx samples and printable PDFs) are available from the ISO resources listed in the standard.
Applications and users
- Print buyers: Capture and communicate formal quality policies and acceptance criteria to suppliers.
- Print service providers & quality labs: Interpret buyer requirements for manual review, reporting, or to inform internal QC checks (note: not for automated loading of production targets).
- Quality management systems (QMS) and MIS vendors: Integrate PRX import/export to standardize exchange of quality metadata across the supply chain.
- Prepress and color management specialists: Use CxF-linked data in PRX to align color targets and tolerances with buyer expectations.
Related standards
- ISO 20616 (series) - other parts of the series address complementary exchange formats.
- ISO 17972‑3 (CxF/X‑3) - normative reference for output target (CxF) data used by PRX.
Keywords: ISO 20616-1, PRX, print quality, XML schema, print quality management, CxF, quality control metadata, print buyer, grading scale.
Open preview (PDF)Graphic technology — File format for quality control and metadata — Part 1: Print requirements eXchange (PRX)
