aboutsummaryrefslogtreecommitdiff
path: root/audio/decoders/adpcm.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'audio/decoders/adpcm.cpp')
-rw-r--r--audio/decoders/adpcm.cpp32
1 files changed, 22 insertions, 10 deletions
diff --git a/audio/decoders/adpcm.cpp b/audio/decoders/adpcm.cpp
index 535652a0b3..2fe509e1f3 100644
--- a/audio/decoders/adpcm.cpp
+++ b/audio/decoders/adpcm.cpp
@@ -71,13 +71,19 @@ int Oki_ADPCMStream::readBuffer(int16 *buffer, const int numSamples) {
int samples;
byte data;
- assert(numSamples % 2 == 0);
+ for (samples = 0; samples < numSamples && !endOfData(); samples++) {
+ if (_decodedSampleCount == 0) {
+ data = _stream->readByte();
+ _decodedSamples[0] = decodeOKI((data >> 4) & 0x0f);
+ _decodedSamples[1] = decodeOKI((data >> 0) & 0x0f);
+ _decodedSampleCount = 2;
+ }
- for (samples = 0; samples < numSamples && !_stream->eos() && _stream->pos() < _endpos; samples += 2) {
- data = _stream->readByte();
- buffer[samples] = decodeOKI((data >> 4) & 0x0f);
- buffer[samples + 1] = decodeOKI(data & 0x0f);
+ // (1 - (count - 1)) ensures that _decodedSamples acts as a FIFO of depth 2
+ buffer[samples] = _decodedSamples[1 - (_decodedSampleCount - 1)];
+ _decodedSampleCount--;
}
+
return samples;
}
@@ -117,13 +123,19 @@ int DVI_ADPCMStream::readBuffer(int16 *buffer, const int numSamples) {
int samples;
byte data;
- assert(numSamples % 2 == 0);
+ for (samples = 0; samples < numSamples && !endOfData(); samples++) {
+ if (_decodedSampleCount == 0) {
+ data = _stream->readByte();
+ _decodedSamples[0] = decodeIMA((data >> 4) & 0x0f, 0);
+ _decodedSamples[1] = decodeIMA((data >> 0) & 0x0f, _channels == 2 ? 1 : 0);
+ _decodedSampleCount = 2;
+ }
- for (samples = 0; samples < numSamples && !_stream->eos() && _stream->pos() < _endpos; samples += 2) {
- data = _stream->readByte();
- buffer[samples] = decodeIMA((data >> 4) & 0x0f);
- buffer[samples + 1] = decodeIMA(data & 0x0f, _channels == 2 ? 1 : 0);
+ // (1 - (count - 1)) ensures that _decodedSamples acts as a FIFO of depth 2
+ buffer[samples] = _decodedSamples[1 - (_decodedSampleCount - 1)];
+ _decodedSampleCount--;
}
+
return samples;
}