Appendix 2B – JPEG2000 specifications
The Supplier must deliver the image files in accordance with the specifications below.
- Encoding:JPEG 2000, Part 1 (ISO/IEC 15444-1. JPEG 2000 image coding system - Part 1: Core coding system)
- File format:JP2 (ISO/IEC 15444-1. JPEG 2000 image coding system - Part 1: Core coding system, Annex I: JP2 file format)
- Colour space and depth:Greyscale, 8 bits per pixel
- Transformation/compression:Lossless (5-3 reversible)
- Decomposition levels: 6 levels, each half the size of the previous.
- Quality layers:Multiple quality layers, highest quality should be lossless. 16 layers. After lossless, 4 bits/pixel, 2 bits/pixel, and so on down to 0.015625 bits/pixel.
- Progression order:Resolution level-position-component-layer (RPCL)
- Tile size:1024 x 1024 pixels
- Code-block size:64x64
- Embedded metadata:No embedded metadata in the JP2 file. Metadata instead should be stored in separate MIX files (see elsewhere).
- Coder bypass mode:Yes.
- Tile-length markers (TLM): Yes.
- Start of Packet (SOP) markers:Yes.
- End of Packet header (EPH) markers:Yes.
- Segmentation symbols:Yes.
- Regions of interest (ROI):No.
- Note: Be careful with generating JP2-files from TIFF files that have colours coded in the palette-format. We have experienced problems with our encoder in that case. Namely clearly deteriorated graphics especially visible along the edges of printed letters.