ISO/TS 20498-4:2020

TECHNICAL ISO/TS
SPECIFICATION 20498-4
First edition
2020-10
Traditional Chinese medicine —
Computerized tongue image analysis
system —
Part 4:
Peripheral visual instruments
Médecine traditionnelle chinoise — Système d’analyse d’images
numérisées de la langue —
Partie 4: Instruments visuels périphériques
Reference number
©
ISO 2020
© ISO 2020
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ii © ISO 2020 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Performance . 2
4.1 Colour reproduction . 2
4.2 Display resolution . 2
4.3 Distortion . 2
4.4 Viewing environment . 3
Annex A (informative) sRGB values of colour chart . 5
Bibliography . 6
Foreword
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iv © ISO 2020 – All rights reserved

TECHNICAL SPECIFICATION ISO/TS 20498-4:2020(E)
Traditional Chinese medicine — Computerized tongue
image analysis system —
Part 4:
Peripheral visual instruments
1 Scope
This document specifies the performance criteria of peripheral visual instruments in the computerized
tongue image analysis system (CTIS), including colour reproduction, distortion and resolution.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/TS 20498-3, Computerized tongue image analysis system — Part 3: Colour chart
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
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