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#include "engine/cachingreader/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::audio::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(std::move(sampleBuffer)) {
DEBUG_ASSERT(m_sampleBuffer.length() == kSamples);
}
void CachingReaderChunk::init(SINT index) {
DEBUG_ASSERT(m_index == kInvalidChunkIndex || index == kInvalidChunkIndex);
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 {
DEBUG_ASSERT(m_index != kInvalidChunkIndex);
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) {
DEBUG_ASSERT(m_index != kInvalidChunkIndex);
const auto sourceFrameIndexRange = frameIndexRange(pAudioSource);
mixxx::AudioSourceStereoProxy audioSourceProxy(
pAudioSource,
tempOutputBuffer);
DEBUG_ASSERT(
audioSourceProxy.getSignalInfo().getChannelCount() ==
kChannels);
m_bufferedSampleFrames =
audioSourceProxy.readSampleFrames(
mixxx::WritableSampleFrames(
sourceFrameIndexRange,
mixxx::SampleBuffer::WritableSlice(m_sampleBuffer)));
DEBUG_ASSERT(m_bufferedSampleFrames.frameIndexRange().empty() ||
m_bufferedSampleFrames.frameIndexRange() <= sourceFrameIndexRange);
return m_bufferedSampleFrames.frameIndexRange();
}
mixxx::IndexRange CachingReaderChunk::readBufferedSampleFrames(
CSAMPLE* sampleBuffer,
const mixxx::IndexRange& frameIndexRange) const {
DEBUG_ASSERT(m_index != kInvalidChunkIndex);
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 {
DEBUG_ASSERT(m_index != kInvalidChunkIndex);
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(std::move(sampleBuffer)),
m_state(FREE),
m_pPrev(nullptr),
m_pNext(nullptr) {
}
void CachingReaderChunkForOwner::init(SINT index) {
// Must not be accessed by a worker!
DEBUG_ASSERT(m_state != READ_PENDING);
// Must not be referenced in MRU/LRU list!
DEBUG_ASSERT(!m_pNext);
DEBUG_ASSERT(!m_pPrev);
CachingReaderChunk::init(index);
m_state = READY;
}
void CachingReaderChunkForOwner::free() {
// Must not be accessed by a worker!
DEBUG_ASSERT(m_state != READ_PENDING);
// Must not be referenced in MRU/LRU list!
DEBUG_ASSERT(!m_pNext);
DEBUG_ASSERT(!m_pPrev);
CachingReaderChunk::init(kInvalidChunkIndex);
m_state = FREE;
}
void CachingReaderChunkForOwner::insertIntoListBefore(
CachingReaderChunkForOwner** ppHead,
CachingReaderChunkForOwner** ppTail,
CachingReaderChunkForOwner* pBefore) {
DEBUG_ASSERT(m_state == READY);
// Both head and tail need to be adjusted
DEBUG_ASSERT(ppHead);
DEBUG_ASSERT(ppTail);
// Cannot insert before itself
DEBUG_ASSERT(this != pBefore);
// Must not yet be referenced in MRU/LRU list
DEBUG_ASSERT(this != *ppHead);
DEBUG_ASSERT(this != *ppTail);
DEBUG_ASSERT(!m_pNext);
DEBUG_ASSERT(!m_pPrev);
if (kLogger.traceEnabled()) {
kLogger.trace()
<< "insertIntoListBefore()"
<< this
<< ppHead << *ppHead
<< ppTail << *ppTail
<< pBefore;
}
if (pBefore) {
// List must already contain one or more item, i.e. has both
// a head and a tail
DEBUG_ASSERT(*ppHead);
DEBUG_ASSERT(*ppTail);
m_pPrev = pBefore->m_pPrev;
pBefore->m_pPrev = this;
m_pNext = pBefore;
if (*ppHead == pBefore) {
// Replace head
*ppHead = this;
}
} else {
// Append as new tail
m_pPrev = *ppTail;
*ppTail = this;
if (m_pPrev) {
m_pPrev->m_pNext = this;
}
if (!*ppHead) {
// Initialize new head if the list was empty before
*ppHead = this;
}
}
}
void CachingReaderChunkForOwner::removeFromList(
CachingReaderChunkForOwner** ppHead,
CachingReaderChunkForOwner** ppTail) {
DEBUG_ASSERT(m_state == READY);
// Both head and tail need to be adjusted
DEBUG_ASSERT(ppHead);
DEBUG_ASSERT(ppTail);
if (kLogger.traceEnabled()) {
kLogger.trace()
<< "removeFromList()"
<< this
<< ppHead << *ppHead
<< ppTail << *ppTail;
}
// Disconnect this chunk from the double-linked list
const auto pPrev = m_pPrev;
const auto pNext = m_pNext;
m_pPrev = nullptr;
m_pNext = nullptr;
// Reconnect the adjacent list items and adjust head/tail if needed
if (pPrev) {
DEBUG_ASSERT(this == pPrev->m_pNext);
pPrev->m_pNext = pNext;
} else {
// Only the current head item doesn't have a predecessor
if (this == *ppHead) {
// pNext becomes the new head
*ppHead = pNext;
} else {
// Item was not part the list and must not have any successor
DEBUG_ASSERT(!pPrev);
}
}
if (pNext) {
DEBUG_ASSERT(this == pNext->m_pPrev);
pNext->m_pPrev = pPrev;
} else {
// Only the current tail item doesn't have a successor
if (this == *ppTail) {
// pPrev becomes the new tail
*ppTail = pPrev;
} else {
// Item was not part the list and must not have any predecessor
DEBUG_ASSERT(!pPrev);
}
}
}
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