DPCM Tools

Zeta's tools for DPCM sample generation, targeting Ricoh 2A03. Most tools can generate both raw .dmc and also .fti instruments, for use with FamiTracker and its various forks.

To use, make sure you're running some flavor of Python 3, then clone the source directory and directly run the tools. No external dependencies yet, just the standard library.

Looper

Generates looping melodic DPCM samples. Given a target note, it works out a sample length and a number of repeats of a source waveform to fill out that length and get the note as close to in-tune as possible. In addition to basic shapes, a custom waveform can be provided; use 8-bit PCM in Mono for the .wav file.

This tool prioritizes clean loops, trading perfect tuning as necessary. Generated samples will vary in length, and a few notes (especially in the extreme bass) cannot be reliably tuned. The target size and acceptable tuning error can be tweaked. Don't be afraid to experiment!

usage: looper.py [-h] [-s DIRECTORY] [-i INSTRUMENT] [--prefix PREFIX]
                 [-g GENERATOR] [-w WAVEFILE] [-v VOLUME]
                 [-e ERROR_THRESHOLD] [-b BIAS] [-l MAX_LENGTH]
                 [--safe-volume | --no-safe-volume] [-d DELTA]
                 [--repitch | --no-repitch] [--fullname FULLNAME]
                 notes

Automatically generate looping DPCM samples

positional arguments:
  notes                 Notes to generate. Ex: gs2,f3-a3

optional arguments:
  -h, --help            show this help message and exit
  -s DIRECTORY, --directory DIRECTORY
                        Directory to store generated samples as .dmc
  -i INSTRUMENT, --instrument INSTRUMENT
                        FamiTracker instrument filename to generate
  --prefix PREFIX       Samples will be named [prefix]-[note] (default:
                        filename)

Sample Generation:
  -g GENERATOR, --generator GENERATOR
                        One of: sine, square, triangle, sawtooth, wave,
                        artificial_ramp
  -w WAVEFILE, --wavefile WAVEFILE
                        For the wave generator. Should contain one loop,
                        like N163.
  -v VOLUME, --volume VOLUME
                        Linear volume multiplier for generated waveforms
  -e ERROR_THRESHOLD, --error-threshold ERROR_THRESHOLD
                        Prefer smaller samples within this tuning percentage
                        (default: 0%)
  -b BIAS, --bias BIAS  Bias generated samples in this direction. (default:
                        0)
  -l MAX_LENGTH, --max-length MAX_LENGTH
                        Longest sample size to consider. Generally improves
                        tuning, costs more space. (default: 255)
  --safe-volume, --no-safe-volume
                        Scale volume for high notes, to avoid triangle shape
                        creep. (default: True)

FamiTracker Instruments:
  -d DELTA, --delta DELTA
                        Set the delta counter when playback begins
  --repitch, --no-repitch
                        Fill out an instrument's lower range with repitched
                        samples (default: True)
  --fullname FULLNAME   The full name of this instrument, show in
                        FamiTracker's UI

    Examples:
      Sawtooth, Sunsoft style:
        looper.py -g sawtooth -i sunsaw.fti as2-d3

      Half-volume triangle, positive bias:
        looper.py -g triangle -v 0.5 -b 1 -i tri-50.fti c4-c5

      Custom waveform:
        looper.py -g wave -w organ.wav -i organ.fti c4-c5

Repitcher

Melodically repitches a single wave file into many individual DPCM samples, with options to tweak the resulting size and quality. The generated instrument can fill in the lower notes with hardware repitching. Other than a basic resample, no modification is done to the source waveform, so you'll want to apply your low pass and other tweaks in your favorite DAW before processing.

usage: repitcher.py [-h] [-r REFERENCE] [-i INSTRUMENT] [--prefix PREFIX]
                    [-l MAX_LENGTH] [-q QUALITY] [-d DELTA]
                    [--repitch | --no-repitch] [--fullname FULLNAME]
                    source notes

Generate melodic DPCM from a single source sample

positional arguments:
  source                Path to a source .wav file. Accepts unsigned 8bit,
                        signed 16bit, mono or stereo.
  notes                 Notes to generate. Ex: gs2,f3-a3

optional arguments:
  -h, --help            show this help message and exit
  -r REFERENCE, --reference REFERENCE
                        Reference note for the source waveform, used for
                        repitching. (default: C4)
  -i INSTRUMENT, --instrument INSTRUMENT
                        FamiTracker instrument filename to generate
  --prefix PREFIX       Samples will be named [prefix]-[note] (default:
                        filename)

Sample Generation:
  -l MAX_LENGTH, --max-length MAX_LENGTH
                        Samples longer than this will be truncated. Values
                        larger than 4081 are invalid. (default: 4081)
  -q QUALITY, --quality QUALITY
                        DPCM playback rate, ranging from 0 - 15. (default:
                        15)

FamiTracker Instruments:
  -d DELTA, --delta DELTA
                        Set the delta counter when playback begins
  --repitch, --no-repitch
                        Fill out an instrument's lower range with repitched
                        samples (default: True)
  --fullname FULLNAME   The full name of this instrument, show in
                        FamiTracker's UI