Crate oxideav_mod 

Amiga ProTracker / SoundTracker module (“MOD”) support, plus a structural parser for Scream Tracker v1 (.stm) files.

MOD files are self-contained song data: a 20-byte title, 31 sample descriptors, a pattern order list, a 4-character signature that identifies the channel count, 64×N-channel patterns, then raw signed 8-bit sample bodies.

This crate registers:

• A container (mod) that slurps the entire file and emits it as a single packet. The “packets” abstraction isn’t natural for MOD — playback is driven by song position + effect state, not per-packet decode — so the container just delivers the bytes to the codec.
• A mixed-stereo decoder under codec id CODEC_ID_STR = "mod". Emits one interleaved S16 stereo AudioFrame every ~1024 samples; the drop-in option for plug-and-play playback. Stereo pan defaults to a partial L/R separation rather than the strict Amiga hard pan — see player::PlayerState::set_pan_separation for the override and the rationale (Protracker-effects-MODFIL12.txt §11 itself recommends against full hard pan “Especially when using headphones”).
• A per-channel decoder under codec id CODEC_ID_PLANAR_STR = "mod_planar". Emits planar S16P AudioFrames with one plane per MOD tracker channel (4 / 6 / 8 / … / 32), post-volume but pre-pan/pre-mix. Consumers that need independent channel streams (DAWs, visualisers, per-instrument remastering) select this codec id instead of "mod".
• A container (stm) that recognises Scream Tracker v1 modules (pre-S3M, 4-channel-fixed), parses the header + instrument table + pattern data + sample bodies, and exposes them for downstream consumers. A minimum STM playback engine is wired via the shared mixer::MixerVoice core and mixer::StmC3Pitch pitch model; drive it via stm_player::StmPlayerState::render. The associated codec id CODEC_ID_STM_STR = "stm" is still a parsing-only decoder registration (it validates the packet then returns an explicit unsupported), because effect support and global mixer parameters are not yet feature-complete; callers wiring STM into the broader oxideav pipeline should hook up StmPlayerState::render directly for now.
• A container (xm) that recognises FastTracker 2 Extended Module files by the 17-byte "Extended Module: " ASCII banner at offset 0. Parses the 336-byte file header (banner, module/tracker names, version, header size, song length, restart position, channel / pattern / instrument counts, frequency-table flag, default tempo / BPM, 256-entry order table), the variable-length bit-packed patterns (note / instrument / volume-column / effect / effect-param, each optional per mask byte), and the instrument table (per-note sample mapping, volume + panning envelopes, vibrato state, fadeout, multiple samples per instrument with delta-encoded 8- or 16-bit PCM bodies). A minimum XM playback engine is wired via the shared mixer::MixerVoice core and mixer::XmPitch pitch model (both Amiga and Linear frequency tables supported); drive it via xm_player::XmPlayerState::render. Volume + panning envelopes (tick-based linear interpolation with sustain-point hold and loop-start/loop-end looping), fadeout (on key-off / note 97), and key-off events are supported. Vibrato, tone portamento, and the bulk of the Bxy/Dxy/Exy/Fxy/Kxy/Lxy effect space remain unimplemented. The codec id CODEC_ID_XM_STR = "xm" remains a parsing-only decoder pending effect-set completeness — use xm::parse_header / xm::parse_patterns / xm::parse_instruments / xm::extract_sample_bodies for structural access, or drive XmPlayerState directly for PCM output.

The tracker convention of exposing per-channel streams alongside a mixed stereo mix is shared across tracker formats — see MEMORY.md → MOD multichannel for the broader sketch.

Decode only — there is no MOD or STM encoder, by design.

Modules

container

MOD as a container format.

decoder

MOD codec decoder — ProTracker playback.

header

ProTracker / SoundTracker MOD header parser.

mixer

Shared tracker mixer core.

player

ProTracker playback engine.

samples

Sample-body extraction for MOD files.

stm

Scream Tracker v1.0 (“STM”) module parsing.

stm_player

Scream Tracker v1 (.stm) playback engine.

xm

FastTracker 2 Extended Module (“XM”) structural parser.

xm_player

FastTracker 2 Extended Module (.xm) playback engine.

Constants

CODEC_ID_PLANAR_STR

Codec id for the planar per-channel MOD decoder.

CODEC_ID_STM_STR

Codec id for the STM (Scream Tracker v1) parsing-only decoder.

CODEC_ID_STR

Codec id for the mixed-stereo MOD decoder.

CODEC_ID_XM_STR

Codec id for the XM (FastTracker 2 Extended Module) parsing-only decoder.

Functions

register

Unified entry point: install every codec and container provided by oxideav-mod into a RuntimeContext.

register_codecs

register_containers