oxideav-generator

Pure-Rust synthetic media generator for the oxideav framework. Provides audio synth (sine / square / triangle / sawtooth / Karplus-Strong pluck / white-pink-brown noise / silence), image basics (solid colour, linear / radial gradient, checkerboard, horizontal / vertical stripes), procedural imagery (Mandelbrot + Julia fractals, plasma, Perlin noise), and video (ffmpeg-style testsrc, SMPTE colour bars, animated Mandelbrot zoom, hue-rotating gradient).

Two integration shapes are exposed:

1. Source driver — generate://... URIs, registered through the standard SourceRegistry. Opening one returns a SourceOutput::Frames handle (Box<dyn FrameSource>) — frames are produced natively (audio: one AudioFrame per call until the configured duration is exhausted; image: a single still VideoFrame followed by Eof; video: one VideoFrame per call until the configured frame count is exhausted). Both audio and video URI inputs are supported end-to-end; generate://testsrc?… no longer bails with Unsupported.
2. Zero-input filter — every generator is also exposed as a StreamFilter factory (audio.synth, image.xc, …, video.testsrc, …) that emits frames in flush() without any upstream input.

Dependency-only on oxideav-core and serde_json — no image, no png, no wav crate, no rand. LCG / Perlin / diamond-square are all hand-rolled in tree. (Earlier rounds shipped hand-rolled WAV / PNG encoders for the byte-shaped URI path; those are gone now that the URI path produces frames natively.)

URI catalogue

generate://synth?type=sine&freq=440&duration=5
generate://synth?type=square&freq=220&duration=2&amplitude=0.5
generate://synth?type=pluck&freq=440&decay=0.99&duration=3
generate://synth?type=noise&color=pink&duration=10

generate://xc?color=red&w=640&h=480
generate://xc?color=%23ff0000      # #ff0000 percent-encoded
generate://gradient?w=640&h=480&from=red&to=blue&direction=horizontal
generate://gradient?w=640&h=480&from=red&to=blue&type=radial
generate://pattern?type=checkerboard&w=640&h=480&size=32
generate://fractal?type=mandelbrot&w=640&h=480&cx=-0.5&cy=0&zoom=2&iter=256
generate://fractal?type=julia&w=640&h=480&cx=-0.7&cy=0.27&iter=256
generate://plasma?w=640&h=480&seed=42
generate://noise?type=perlin&w=640&h=480&scale=64&seed=42

CLI shorthands (convert verb only)

The convert verb's arg parser runs every input through oxideav_generator::shorthand::translate before reaching the source registry. Recognised prefixes:

Shorthand	Canonical
xc:red	generate://xc?color=red
xc:#ff0000	generate://xc?color=%23ff0000
pattern:checkerboard	generate://pattern?type=checkerboard
gradient:red-blue	generate://gradient?from=red&to=blue
radial:red-blue	generate://gradient?type=radial&from=red&to=blue
plasma:	generate://plasma
mandelbrot:	generate://fractal?type=mandelbrot
julia:	generate://fractal?type=julia
synth:5,sine,440	generate://synth?duration=5&type=sine&freq=440
testsrc:	generate://testsrc
smptebars:	generate://smptebars
noise:perlin	generate://noise?type=perlin

probe / transcode / remux / run accept the canonical generate:// URI form only — they don't expand shorthands.

Wiring

use oxideav_core::{RuntimeContext, SourceRegistry};

let mut ctx = RuntimeContext::new();
oxideav_source::register(&mut ctx);                      // file://
oxideav_generator::register_source(&mut ctx.sources);    // generate://
oxideav_generator::register_filters(&mut ctx);           // audio.synth, image.xc, ...

Status

Round 2 (2026-05-02): URI source path migrated to the new typed SourceRegistry FrameSource shape — every generate://… URI returns SourceOutput::Frames directly, and the round-1 video-bails-with- Unsupported gotcha is gone. Audio + image + video URIs all work end-to-end with no intermediate encode/decode round-trip; the hand-rolled WAV / PNG emitters that the bytes-shaped path required have been removed (they were internal-only — no public API change for the filter or shorthand surfaces). The filter API and CLI shorthand translator are unchanged.

Round 1: audio basics + image basics + procedural images + video generators all landed.

CSS colour parser

Hand-rolled. Accepts a curated subset of the CSS/HTML4 named colours plus #RGB, #RGBA, #RRGGBB, and #RRGGBBAA.

Determinism

All randomness is seeded — every generator that takes a seed= query parameter is bit-deterministic across builds. Defaults: seed=42 for plasma / Perlin, seed=0x12345678 for white / pink / brown noise.