--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/semiconginev2/old/resources/audio.nim	Wed Jul 17 21:01:37 2024 +0700
@@ -0,0 +1,93 @@
+import std/os
+import std/streams
+import std/strformat
+import std/endians
+
+import ../core/audiotypes
+
+type
+  Encoding {.size: sizeof(uint32).} = enum
+    # Unspecified = 0
+    # Uint8Ulaw = 1
+    # Int8 = 2
+    Int16 = 3
+    # Int24 = 4
+    # Int32 = 5
+    # Float32 = 6
+    # Float64 = 7
+
+  AuHeader = object
+    magicNumber: uint32
+    dataOffset: uint32
+    dataSize: uint32
+    encoding: Encoding
+    sampleRate: uint32
+    channels: uint32
+
+proc readSample(stream: Stream, encoding: Encoding, channels: int): Sample =
+  result[0] = stream.readint16()
+  swapEndian16(addr result[0], addr result[0])
+
+  if channels == 2:
+    result[1] = stream.readint16()
+    swapEndian16(addr result[1], addr result[1])
+  else:
+    result[1] = result[0]
+
+# https://en.wikipedia.org/wiki/Au_file_format
+proc ReadAU*(stream: Stream): Sound =
+  var header: AuHeader
+
+  for name, value in fieldPairs(header):
+    var bytes: array[4, uint8]
+    stream.read(bytes)
+    swap(bytes[0], bytes[3])
+    swap(bytes[1], bytes[2])
+    value = cast[typeof(value)](bytes)
+
+  assert header.magicNumber == 0x2e736e64
+  if header.sampleRate != AUDIO_SAMPLE_RATE:
+    raise newException(Exception, &"Only support sample rate of {AUDIO_SAMPLE_RATE} Hz but got {header.sampleRate} Hz, please resample (e.g. ffmpeg -i <infile> -ar {AUDIO_SAMPLE_RATE} <outfile>)")
+  if not (header.channels in [1'u32, 2'u32]):
+    raise newException(Exception, "Only support mono and stereo audio at the moment (1 or 2 channels), but found " & $header.channels)
+
+  var annotation: string
+  stream.read(annotation)
+
+  result = new Sound
+  stream.setPosition(int(header.dataOffset))
+  while not stream.atEnd():
+    result[].add stream.readSample(header.encoding, int(header.channels))
+
+{.compile: currentSourcePath.parentDir() & "/stb_vorbis.c".}
+
+proc stb_vorbis_decode_memory(mem: pointer, len: cint, channels: ptr cint, sample_rate: ptr cint, output: ptr ptr cshort): cint {.importc.}
+proc free(p: pointer) {.importc.}
+
+proc ReadVorbis*(stream: Stream): Sound =
+  var
+    data = stream.readAll()
+    channels: cint
+    sampleRate: cint
+    output: ptr cshort
+
+  var nSamples = stb_vorbis_decode_memory(addr data[0], cint(data.len), addr channels, addr sampleRate, addr output)
+
+  if nSamples < 0:
+    raise newException(Exception, &"Unable to read ogg/vorbis sound file, error code: {nSamples}")
+  if sampleRate != AUDIO_SAMPLE_RATE:
+    raise newException(Exception, &"Only support sample rate of {AUDIO_SAMPLE_RATE} Hz but got {sampleRate} Hz, please resample (e.g. ffmpeg -i <infile> -acodec libvorbis -ar {AUDIO_SAMPLE_RATE} <outfile>)")
+
+  result = new Sound
+  if channels == 2:
+    result[].setLen(int(nSamples))
+    copyMem(addr result[][0], output, nSamples * sizeof(Sample))
+    free(output)
+  elif channels == 1:
+    for i in 0 ..< nSamples:
+      let value = cast[ptr UncheckedArray[int16]](output)[i]
+      result[].add [value, value]
+    free(output)
+  else:
+    free(output)
+    raise newException(Exception, "Only support mono and stereo audio at the moment (1 or 2 channels), but found " & $channels)