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#include "engine/cachingreaderchunk.h"
#include <QtDebug>
#include "sources/audiosourcestereoproxy.h"
#include "engine/engine.h"
#include "util/math.h"
#include "util/sample.h"
#include "util/logger.h"
namespace {
mixxx::Logger kLogger("CachingReaderChunk");
const SINT kInvalidChunkIndex = -1;
} // anonymous namespace
// One chunk should contain 1/2 - 1/4th of a second of audio.
// 8192 frames contain about 170 ms of audio at 48 kHz, which
// is well above (hopefully) the latencies people are seeing.
// At 10 ms latency one chunk is enough for 17 callbacks.
// Additionally the chunk size should be a power of 2 for
// easier memory alignment.
// TODO(XXX): The optimum value of the "constant" kFrames depends
// on the properties of the AudioSource as the remarks above suggest!
const mixxx::AudioSignal::ChannelCount CachingReaderChunk::kChannels = mixxx::kEngineChannelCount;
const SINT CachingReaderChunk::kFrames = 8192; // ~ 170 ms at 48 kHz
const SINT CachingReaderChunk::kSamples =
CachingReaderChunk::frames2samples(CachingReaderChunk::kFrames);
CachingReaderChunk::CachingReaderChunk(
mixxx::SampleBuffer::WritableSlice sampleBuffer)
: m_index(kInvalidChunkIndex),
m_sampleBuffer(sampleBuffer) {
DEBUG_ASSERT(sampleBuffer.length() == kSamples);
}
CachingReaderChunk::~CachingReaderChunk() {
}
void CachingReaderChunk::init(SINT index) {
m_index = index;
m_bufferedSampleFrames.frameIndexRange() = mixxx::IndexRange();
}
// Frame index range of this chunk for the given audio source.
mixxx::IndexRange CachingReaderChunk::frameIndexRange(
const mixxx::AudioSourcePointer& pAudioSource) const {
if (!pAudioSource) {
return mixxx::IndexRange();
}
const SINT minFrameIndex =
pAudioSource->frameIndexMin() +
frameIndexOffset();
return intersect(
mixxx::IndexRange::forward(minFrameIndex, kFrames),
pAudioSource->frameIndexRange());
}
mixxx::IndexRange CachingReaderChunk::bufferSampleFrames(
const mixxx::AudioSourcePointer& pAudioSource,
mixxx::SampleBuffer::WritableSlice tempOutputBuffer) {
const auto sourceFrameIndexRange = frameIndexRange(pAudioSource);
mixxx::AudioSourceStereoProxy audioSourceProxy(
pAudioSource,
tempOutputBuffer);
DEBUG_ASSERT(audioSourceProxy.channelCount() == kChannels);
m_bufferedSampleFrames =
audioSourceProxy.readSampleFrames(
mixxx::WritableSampleFrames(
sourceFrameIndexRange,
mixxx::SampleBuffer::WritableSlice(m_sampleBuffer)));
DEBUG_ASSERT(m_bufferedSampleFrames.frameIndexRange() <= sourceFrameIndexRange);
return m_bufferedSampleFrames.frameIndexRange();
}
mixxx::IndexRange CachingReaderChunk::readBufferedSampleFrames(
CSAMPLE* sampleBuffer,
const mixxx::IndexRange& frameIndexRange) const {
const auto copyableFrameIndexRange =
intersect(frameIndexRange, m_bufferedSampleFrames.frameIndexRange());
if (!copyableFrameIndexRange.empty()) {
const SINT dstSampleOffset =
frames2samples(copyableFrameIndexRange.start() - frameIndexRange.start());
const SINT srcSampleOffset =
frames2samples(copyableFrameIndexRange.start() - m_bufferedSampleFrames.frameIndexRange().start());
const SINT sampleCount = frames2samples(copyableFrameIndexRange.length());
SampleUtil::copy(
sampleBuffer + dstSampleOffset,
m_bufferedSampleFrames.readableData(srcSampleOffset),
sampleCount);
}
return copyableFrameIndexRange;
}
mixxx::IndexRange CachingReaderChunk::readBufferedSampleFramesReverse(
CSAMPLE* reverseSampleBuffer,
const mixxx::IndexRange& frameIndexRange) const {
const auto copyableFrameIndexRange =
intersect(frameIndexRange, m_bufferedSampleFrames.frameIndexRange());
if (!copyableFrameIndexRange.empty()) {
const SINT dstSampleOffset =
frames2samples(copyableFrameIndexRange.start() - frameIndexRange.start());
const SINT srcSampleOffset =
frames2samples(copyableFrameIndexRange.start() - m_bufferedSampleFrames.frameIndexRange().start());
const SINT sampleCount = frames2samples(copyableFrameIndexRange.length());
SampleUtil::copyReverse(
reverseSampleBuffer - dstSampleOffset - sampleCount,
m_bufferedSampleFrames.readableData(srcSampleOffset),
sampleCount);
}
return copyableFrameIndexRange;
}
CachingReaderChunkForOwner::CachingReaderChunkForOwner(
mixxx::SampleBuffer::WritableSlice sampleBuffer)
: CachingReaderChunk(sampleBuffer),
m_state(FREE),
m_pPrev(nullptr),
m_pNext(nullptr) {
}
CachingReaderChunkForOwner::~CachingReaderChunkForOwner() {
}
void CachingReaderChunkForOwner::init(SINT index) {
DEBUG_ASSERT(READ_PENDING != m_state);
CachingReaderChunk::init(index);
m_state = READY;
}
void CachingReaderChunkForOwner::free() {
DEBUG_ASSERT(READ_PENDING != m_state);
CachingReaderChunk::init(kInvalidChunkIndex);
m_state = FREE;
}
void CachingReaderChunkForOwner::insertIntoListBefore(
CachingReaderChunkForOwner* pBefore) {
DEBUG_ASSERT(m_pNext == nullptr);
DEBUG_ASSERT(m_pPrev == nullptr);
DEBUG_ASSERT(m_state != READ_PENDING); // Must not be accessed by a worker!
m_pNext = pBefore;
if (pBefore) {
if (pBefore->m_pPrev) {
m_pPrev = pBefore->m_pPrev;
DEBUG_ASSERT(m_pPrev->m_pNext == pBefore);
m_pPrev->m_pNext = this;
}
pBefore->m_pPrev = this;
}
}
void CachingReaderChunkForOwner::removeFromList(
CachingReaderChunkForOwner** ppHead,
CachingReaderChunkForOwner** ppTail) {
// Remove this chunk from the double-linked list...
CachingReaderChunkForOwner* pNext = m_pNext;
CachingReaderChunkForOwner* pPrev = m_pPrev;
m_pNext = nullptr;
m_pPrev = nullptr;
// ...reconnect the remaining list elements...
if (pNext) {
DEBUG_ASSERT(this == pNext->m_pPrev);
pNext->m_pPrev = pPrev;
}
if (pPrev) {
DEBUG_ASSERT(this == pPrev->m_pNext);
pPrev->m_pNext = pNext;
}
// ...and adjust head/tail.
if (ppHead && (this == *ppHead)) {
*ppHead = pNext;
}
if (ppTail && (this == *ppTail)) {
*ppTail = pPrev;
}
}
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