EXR Format Supported and Unsupported Features

This is a tracking issue for EXR features which are currently supported and which are not.

Supported pixel types:

• Half: 16-bit floating-point numbers
• Float: 32-bit IEEE-754 floating-point numbers
• Uint: 32-bit unsigned integers;

Supported compression's for decoding:

• NO_COMPRESSION: pixel data is not compressed
• RLE_COMPRESSION: run length encoding
• ZIPS_COMPRESSION: zlib compression, one scan line at a time
• ZIP_COMPRESSION: zlib compression, in blocks of 16 scan lines
• B44_COMPRESSION: lossy 4-by-4 pixel block compression, fixed compression rate
• B44A_COMPRESSION: lossy 4-by-4 pixel block compression, flat fields are compressed more
• DWAA_COMPRESSION: lossy DCT based compression, in blocks of 32 scanlines. More efficient for partial buffer access.
• DWAB_COMPRESSION: lossy DCT based compression, in blocks of 256 scanlines. More efficient space-wise and faster to decode full frames than DWAA_COMPRESSION.
• PIZ_COMPRESSION: piz-based wavelet compression
• PXR24_COMPRESSION: lossy 24-bit float compression, Pull-Request
• HTJ2K256_COMPRESSION: JPEG 2000 lossless coding, in blocks of 256 scanlines and using the High-Throughput block coder specified in Rec. ITU-T T.814 and ISO/IEC 15444-15. The compressor offers both speed and high coding efficiency.
• HTJ2K32_COMPRESSION: Same as HTJ2K256_COMPRESSION, but in blocks of 32 scanlines, More efficient for partial buffer access, but slightly less efficient space-wise.

Other EXR image features:

• Tiled images
• Multi-part EXR files

The EXR specification can be found here: https://openexr.com/en/latest/index.html

Start with the EXR specification linked in the issue and compare its unchecked compression and image features with the repository's current EXR support. Done means implementing the selected missing features, validating them against suitable EXR files or tests, and updating the tracking checklist.