Crate ultrahdr 

Safe Rust bindings for Google’s libultrahdr, the reference implementation of UltraHDR gain-map JPEG encoding/decoding.

The crate exposes a small, stateful API that mirrors the C library while handling memory ownership and validation for you:

• Decoder reads JPEGs, exposes gain-map metadata (if present), and produces packed pixel views.
• Encoder writes UltraHDR or plain JPEGs from packed pixel buffers or compressed inputs.
• RawImage, CompressedImage, and DecodedPackedView describe image buffers without requiring you to depend on sys directly.

For a higher-level walkthrough, see examples/ultrahdr_app.rs in this crate and the CLI in the companion ultrahdr-bake package.

Re-exports

pub use ultrahdr_sys as sys;

Structs

CompressedImage

Borrowed descriptor over a caller-provided compressed JPEG buffer.

DecodedPacked

Owned packed pixels plus metadata returned by a [Decoder].

DecodedPackedView

Borrowed view over packed pixels owned by a [Decoder].

Decoder

UltraHDR JPEG decoder. Owns the underlying uhdr_codec_private_t and provides safe access to decoded pixel buffers and gain-map metadata.

EncodedImage

Owned compressed JPEG (and optional gain-map) returned by an [Encoder].

EncodedView

Borrowed view over an encoded stream owned by an [Encoder] or [Decoder].

Encoder

UltraHDR JPEG encoder. Owns the underlying uhdr_codec_private_t and can be reused across multiple encodes by calling reset.

Error

Error produced by the safe wrappers around libultrahdr.

GainMapMetadata

Parsed metadata describing an embedded gain map.

OwnedPackedImage

Owns a packed raw buffer and exposes it as uhdr_raw_image.

RawImage

Borrowed descriptor over a caller-provided packed pixel buffer.

Constants

SDR_WHITE_NITS

Nominal SDR diffuse white used by libultrahdr for capacity math (ISO/TS 22028-5).

Functions

bytes_per_pixel

Bytes-per-pixel helper for the supported packed formats.

Type Aliases

Codec

Output codec to write.

ColorGamut

Scene-referred color gamut.

ColorRange

Chroma sample range.

ColorTransfer

Transfer function describing the relationship between encoded values and scene light.

EncPreset

Encoder tuning preset.

ErrorCode

Error codes returned by the underlying C API.

ImgFormat

Pixel layout for packed buffers accepted/returned by libultrahdr.

ImgLabel

Whether an image is the base view or the gain map.

Result

Result alias used throughout the crate.