lib-image · crate

kinogaki-png

Libraryenvironment

PNG images (ISO/IEC 15948, W3C PNG Third Edition) over kinogaki_deflate.

Repository: lib-image (kinogaki/lib-image)
Folder: libs/lib-image/crates/png
Source: 4 files, 932 lines
Tests: 1 file, 195 lines

depends onused by tests alonedependencies for tests alone are listed below, not drawn

What it is

PNG images (ISO/IEC 15948, W3C PNG Third Edition) over kinogaki_deflate.

Images are owned and interleaved (Image, shared by every lib-image format): grey, grey and alpha, RGB or RGBA, 8 or 16 bits per sample, straight alpha. decode reads every standard PNG — greyscale, truecolor, indexed, with or without alpha, 1 to 16 bits per sample, interlaced or not, tRNS transparency — keeping the file's channels and sample size; Png reads its chunks first, so a caller knows what decoding takes before it decodes, and decodes until a stop flag is raised; encode writes any Image with a per-row adaptive filter, encode_tagged saying which display its code values are for, display_tag reading that back; decoding ignores color management chunks (samples are taken as sRGB). Chunk CRCs and the zlib checksum are verified.

Depends on

Crate	Repository	As	What it is
`kinogaki-deflate`	lib-image	normal	DEFLATE (RFC 1951) and zlib (RFC 1950) compression and decompression, with the CRC-32 and Adler-32 checksums the formats around them use.
`kinogaki-image`	lib-image	normal	The owned image every lib-image format decodes to and encodes from.

Third-party

None.

Used by

Crate	Repository	As	What it is
`kinogaki-capture-diff`	Core and the app	normal	Compares two sets of UI reference captures (`tools/ui_captures.py compare BEFORE AFTER`).
`kinogaki-comp`	Comp	tests	Comp as an SDK package (`kinogaki.comp`): what fills Studio's Comp context (`kinogaki.core.comp`, core declares it, inside a Render Output object).
`kinogaki-harness`	Core and the app	normal	Studio's test harness: the real editor, its event routing and its background work, driven offscreen with only the packages a test names.
`kinogaki-jpeg-format`	JPEG	tests	JPEG, a format plugin: a JPEG reads as one standard `Image` as the file holds it, and an Image writes as one baseline JPEG.
`kinogaki-layout`	Layout	tests	The Layout context: a page on the 2D canvas and the pieces arranged on it, images and text, back to front in the order their nodes run.
`kinogaki-png-format`	PNG	normal	PNG, a format plugin: a PNG reads as one standard `Image` as the file holds it, and an Image writes as one PNG.
`kinogaki-spectre`	Spectre	tests	Spectre, the spectral path tracer, as a Kinogaki Studio render plugin.
`kinogaki-spectre-testing`	Spectre	normal	What Spectre's GPU tests share (a dev-dependency of the plugin's tests alone): the engine on an offscreen device, waits on its wakes, and images compared with a tolerance.
`kinogaki-ui-wgpu`	lib-ui	normal	kinogaki-ui drawn with wgpu.
`kinogaki-workflows`	Workflows	tests	Tests alone: `tests/workflows` drives what a person does across the plugins the app ships, through the real editor offscreen.

Modules

decode (private)Reading PNGs: their chunks first (Png), then their pixels.531 lines
encode (private)Writing 8-bit RGBA PNGs.139 lines
filter (private)Scanline filters (PNG §7.3, §9): each row is stored as its difference from a predictor over the pixel to the left (a), above (b) and above left (c), bpp bytes apart.179 lines

Public types and traits

At the crate root

Structs Png

Enums DisplayTagError

Type aliases ReadTag

Re-exported from other crates

From kinogaki_deflate Level

From kinogaki_image ImageSamples

By module: 3 public types and traits in 2 modules

decode PngReadTag

encode DisplayTag