wavetable stuff

common/riffwriter.py

@@ -1,3 +1,6 @@
+# riffwriter.py -- Generic RIFF writing framework
+# (C) 2023 a dinosaur (zlib)
+
 from abc import ABC, abstractmethod
 from typing import BinaryIO, List
 

common/wavesampler.py

@@ -1,7 +1,10 @@
+# wavesampler.py -- Support for the non-standard "Sampler" WAVE chunk
+# (C) 2023 a dinosaur (zlib)
+
 import struct
 from enum import Enum
-from riffwriter import AbstractRiffChunk
 from typing import BinaryIO, List
+from common.riffwriter import AbstractRiffChunk
 
 
 class WaveSamplerSMPTEOffset:

common/waveserum.py

@@ -0,0 +1,18 @@
+# waveserum.py -- Serum comment chunk support
+# (C) 2023 a dinosaur (zlib)
+
+from enum import Enum
+from common.wavewriter import WaveCommentChunk
+
+
+class SerumWavetableInterpolation(Enum):
+	NONE = 0
+	LINEAR_XFADE = 1
+	SPECTRAL_MORPH = 2
+
+
+class WaveSerumCommentChunk(WaveCommentChunk):
+	def __init__(self, size: int, mode: SerumWavetableInterpolation, factory=False):
+		comment = f"<!>{size: <4} {mode.value}{'1' if factory else '0'}000000"
+		comment += " wavetable (www.xferrecords.com)"
+		super().__init__(comment.encode("ascii"))

common/wavewriter.py

@@ -1,8 +1,11 @@
+# wavewriter.py -- Extensible WAVE writing framework
+# (C) 2023 a dinosaur (zlib)
+
 import struct
 from abc import abstractmethod
 from enum import Enum
 from typing import BinaryIO, List
-from riffwriter import RiffFile, AbstractRiffChunk
+from common.riffwriter import RiffFile, AbstractRiffChunk
 
 
 class WaveSampleFormat(Enum):
@@ -46,6 +49,11 @@ class WaveAbstractFormatChunk(AbstractRiffChunk):
 				self.bitdepth()))
 
 
+class WaveFile(RiffFile):
+	def __init__(self, format: WaveAbstractFormatChunk, chunks: List[AbstractRiffChunk]):
+		super().__init__(b"WAVE", [format] + chunks)
+
+
 class WavePcmFormatChunk(WaveAbstractFormatChunk):
 	def sampleformat(self) -> WaveSampleFormat: return WaveSampleFormat.PCM
 
@@ -88,8 +96,3 @@ class WaveCommentChunk(AbstractRiffChunk):
 
 	def __init__(self, comment: bytes):
 		self._comment = comment
-
-
-class WaveFile(RiffFile):
-	def __init__(self, format: WaveAbstractFormatChunk, chunks: List[AbstractRiffChunk]):
-		super().__init__(b"WAVE", [format] + chunks)