Thsound

What is this?

An audio library for the homebrew on the Nintendo DS.

Features:

• Playback of 8bit, 16bit pcm, ICM-ADPCM
• Looping
• Noise generation
• Tone generation using the PSG (Square wave, adjustable duty cycle, Equal Temperment tuning)
• Arm7's audio registers accessable via arm9
• Adjustable fade out of individual channels
• Audio sample manager (to simplify playback)
• Samples loadable from .wav files on nitrofs, fat-fs, etc..
• Dynamic manipulation of playing samples.. (stopping playing samples, pitch, volume, pan, etc can all be manipulated)
• Playback channel is selectable
• Presetable defaults for sample rate, volume, and pan.

Todo:

• Add auto channel selection

Functions common to both CPU

thSndInit
This needs to be called at startup on both CPU before any other audio functions.

void thSndInit(void);

Sample loading and management functions

thSampleLoadWav
Load a sample from .wav file. Supported formats are 8bit mono, 16bit mono, and IMA-ADPCM. Stereo sample support MAY be added later.

• name - name of file to load

Returns pointer to newly created sample.

thSample_t *thSampleLoadWav(const char *name);

thSampleCreate
Create a sample from raw audio data.

• start - pointer to start of sample in memory
• len - length of sample (in samples)
• loopstart - Loop point of sample. in number of samples from start.
• rate - sample rate in hertz (44100, 11025, etc etc)
• opts - options. Should include one each of: SNDPCM8, SNDPCM16, SNDADPCM. Additionally may OR on SNDLOOP (or even specify a default volume, pan, but wont get into this yet.. :P)

Returns Pointer to newly created sample.

thSample_t *thSampleCreate(void *start, int len, void *loopstart, int rate, u8 opts);

thSampleDestroy
Unloads a sample from memory. If it was loaded from .wav file will automagically unload that as well.. :p

void thSampleDestroy(thSample_t *thSample);

General Sound Functions

thPlayDefaults
Sets default sample playback options.

void thPlayDefaults(int rate, char level, char pan, u32 flags);

thSndPlaySample
Starts playing a previously loaded sample.

• chan - channel to use for playback
• sample - previously loaded sample
• vol - playback volume (0 to 127)
• pan - playback pan (0 to 127, 0 = left, 127 = right, 64 = center)

void thSndPlaySample(char chan, thSample_t *sample, char vol, char pan);

thSndPlayRaw
Plays a sound in raw format from memory on the specified channel.

• chan - channel to use for playback (0 to 15)
• start - pointer to start of audio data in memory
• len - length of sample (in samples)
• vol - playback volume (0 to 127)
• pan - playback pan (0 to 127, 0 = left, 127 = right, 64 = center)
• loopstart - position to start looping sound (in samples)
• opts - options (such as SNDPCM16, SNDPCM8, etc... see options sections)

void thSndPlayRaw(char chan, void *start, int len, int rate, char vol, char pan, u32 loopstart, u32 opts);

thSndRegDirect
Direct manipulation of the arm7's audio registers from the arm9

• chan - channel to manipulate (0 to 15)
• start - start register
• len - length register
• rate - rate register
• loopstart - loopstart register
• opt - channel's CR register

void thSndRegDirect(char chan, u32 start, int len, int rate, u32 loopstart, u32 opts);

thSndDefPlaySample
Playback a sample use default volume and pan settings

• chan - channel to manipulate (0 to 15)
• sample - pointer to previously loaded audio sample

void thSndDefPlaySample(char chan, thSample_t *sample);

thSndDefPlayRaw
Playback a sample using default volume, pan, and rate settings

• chan - channel to manipulate (0 to 15)
• start - pointer to start of audio data
• len - length of audio data (in samples)

void thSndDefPlayRaw(char chan, void *start, int len);

thSndPlayNoise
Plays noise on the specified channel.

• chan - channel to play noise (14 or 15 only! :)
• rate - rate of playback (use 11025 if in doubt ?_?)
• vol - playback volume (0 to 127)
• pan - playback pan (0 to 127, 0 = left, 127 = right, 64 = center)

void thSndPlayNoise(char chan, u16 rate, char vol, char pan);

thSndPlayNote
Plays a note on the specified channel via the PSG. Note is a square wave with adjustable duty cycle.

• chan - channel to play note (8 to 13 only!)
• note - note to play 0 = c, 1 = c#, 2 = d, 3 = d#, 4 = e, 5 = f, etc etc up to 64 or so (range depends on tuning)
• duty - duty cycle of PSG (0 to 7, use 4 if in doubt ?_?)
• vol - playback volume (0 to 127)
• pan - playback pan (0 to 127, 0 = left, 127 = right, 64 = center)

void thSndPlayNote(char chan, char note, char duty, char vol, char pan);

thSndStop
Immediately stops playing sample, note, noise, or raw data the specified channel.

• chan - channel to stop

void thSndStop(char chan);

Changing Active Parameters

These functions change various attributes after sound has already began playing.

thSndSetVol
Change channel's volume.

• chan - channel to change (0-15)
• vol - playback volume (0 to 127)

void thSndSetVol(char chan, char vol);

thSndSetPan
Change channel's Pan..

• chan - channel to change (0-15)
• pan - playback pan (0 to 127, 0 = left, 127 = right, 64 = center)

void thSndSetPan(char chan, char pan);

thSndSetRate
Change channel's sample rate. Usefull for special effects! :p

• chan - channel to change (0-15)
• rate - new channel frequency (in hertz)

void thSndSetRate(char chan, u32 rate);

Change PSG's duty cycle. thSndSetDuty

• chan - channel to play note (8 to 13 only!)
• duty - duty cycle of PSG (0 to 7, use 4 if in doubt ?_?)

void thSndSetDuty(char chan, char duty);

thSndFade
Initiate a fadeout on specified channel. Useful for fading out repeating wavforms, mp3s, or even can be used with PSG note generation for rudamentary synth effects. Once volume reaches 0 audio playback is stopped on specified channel

• chan - channel to change (0-15)
• faderate - how fast to fade out... higher the number, faster the playback.. need to write formula here eh? 256 would = approx 2 seconds if volume = 127. @_@???

could make this a bit simpler, make faderate a time in ms and do math on arm7...hmmm

void thSndFade(char chan, u16 faderate);