winamp/Src/nu/GaplessRingBuffer.cpp

64 lines
1.5 KiB
C++

#include "GaplessRingBuffer.h"
#include <bfc/platform/types.h>
#include <bfc/error.h>
#include <algorithm>
GaplessRingBuffer::GaplessRingBuffer()
{
pregapBytes = 0;
frameBytes = 0;
postgapBytes = 0;
currentPregapBytes = 0;
}
GaplessRingBuffer::~GaplessRingBuffer()
{
}
int GaplessRingBuffer::Initialize(size_t samples, size_t bps, size_t channels, size_t pregap, size_t postgap)
{
this->frameBytes = channels * bps / 8;
this->currentPregapBytes = this->pregapBytes = pregap * frameBytes;
this->postgapBytes = postgap * frameBytes;
ring_buffer.reserve(samples * frameBytes + pregapBytes);
return NErr_Success;
}
bool GaplessRingBuffer::Empty() const
{
return (ring_buffer.size() <= pregapBytes);
}
size_t GaplessRingBuffer::Read(void *destination, size_t destination_bytes)
{
// make sure we've filled enough of the buffer to satisfy the postgap
if (Empty()) {
return 0;
}
// don't read into postgap area
size_t remaining = ring_buffer.size() - postgapBytes;
destination_bytes = min(remaining, destination_bytes);
return ring_buffer.read(destination, destination_bytes);
}
size_t GaplessRingBuffer::Write(const void *input, size_t input_bytes)
{
// cut pregap if necessary
if (currentPregapBytes) {
size_t cut = min(input_bytes, currentPregapBytes);
currentPregapBytes -= cut;
input_bytes -= cut;
input = (const uint8_t *)input + cut;
}
return ring_buffer.write(input, input_bytes);
}
void GaplessRingBuffer::Reset()
{
currentPregapBytes = pregapBytes;
ring_buffer.clear();
}