From 506d316f5560803e4b24541b18d17ec39e59061b Mon Sep 17 00:00:00 2001
From: Chris Robinson <chris.kcat@gmail.com>
Date: Sun, 31 Dec 2017 16:11:00 -0800
Subject: Wake up the packet send loop when more frames are needed
---
examples/alffplay.cpp | 88 +++++++++++++++++++++++++++++----------------------
1 file changed, 50 insertions(+), 38 deletions(-)
(limited to 'examples/alffplay.cpp')
diff --git a/examples/alffplay.cpp b/examples/alffplay.cpp
index 285ec7f1..60b60a65 100644
--- a/examples/alffplay.cpp
+++ b/examples/alffplay.cpp
@@ -45,8 +45,8 @@ LPALGETSOURCEI64VSOFT alGetSourcei64vSOFT;
const std::chrono::duration<double> AVSyncThreshold(0.01);
const std::chrono::seconds AVNoSyncThreshold(10);
-const std::chrono::milliseconds AudioBufferTime(100); /* Per-buffer */
-#define AUDIO_BUFFER_QUEUE_SIZE 8 /* Number of buffers to queue */
+const std::chrono::milliseconds AudioBufferTime(20); /* Per-buffer */
+#define AUDIO_BUFFER_QUEUE_SIZE 25 /* Number of buffers to queue (~500ms) */
#define MAX_QUEUE_SIZE (15 * 1024 * 1024) /* Bytes of compressed data to keep queued */
#define SAMPLE_CORRECTION_MAX_DIFF 0.05
#define AUDIO_DIFF_AVG_NB 20
@@ -127,8 +127,8 @@ struct AudioState {
int AvgCount;
} mDiff;
- /* Time (in seconds) of the next sample to be buffered */
- std::chrono::duration<double> mCurrentPts;
+ /* Time (in nanoseconds) of the next sample to be buffered */
+ std::chrono::nanoseconds mCurrentPts;
/* Decompressed sample frame, and swresample context for conversion */
AVFrame *mDecodedFrame;
@@ -155,7 +155,7 @@ struct AudioState {
AudioState(MovieState *movie)
: mMovie(movie), mStream(nullptr), mCodecCtx(nullptr)
- , mDiff{0.0, 0.0, 0.0, 0}, mCurrentPts(0.0), mDecodedFrame(nullptr)
+ , mDiff{0.0, 0.0, 0.0, 0}, mCurrentPts(0), mDecodedFrame(nullptr)
, mSwresCtx(nullptr), mDstChanLayout(0), mDstSampleFmt(AV_SAMPLE_FMT_NONE)
, mSamples(nullptr), mSamplesLen(0), mSamplesPos(0), mSamplesMax(0)
, mFormat(AL_NONE), mFrameSize(0), mSource(0), mBufferIdx(0)
@@ -265,6 +265,11 @@ struct MovieState {
std::chrono::microseconds mClockBase;
+ std::mutex mSendMtx;
+ std::condition_variable mSendCond;
+ /* NOTE: false/clear = need data, true/set = no data needed */
+ std::atomic_flag mSendDataGood;
+
std::atomic<bool> mQuit;
AudioState mAudio;
@@ -324,7 +329,7 @@ std::chrono::nanoseconds AudioState::getClock()
* OpenAL's current position, and subtracting the source latency from that
* gives the timestamp of the sample currently at the DAC.
*/
- nanoseconds pts = std::chrono::duration_cast<nanoseconds>(mCurrentPts);
+ nanoseconds pts = mCurrentPts;
if(mSource)
{
ALint64SOFT offset[2];
@@ -405,6 +410,9 @@ int AudioState::decodeFrame()
int ret = avcodec_receive_frame(mCodecCtx, mDecodedFrame);
if(ret == AVERROR(EAGAIN))
{
+ mMovie->mSendDataGood.clear(std::memory_order_relaxed);
+ std::unique_lock<std::mutex>(mMovie->mSendMtx).unlock();
+ mMovie->mSendCond.notify_one();
do {
mQueueCond.wait(lock);
ret = avcodec_receive_frame(mCodecCtx, mDecodedFrame);
@@ -412,6 +420,8 @@ int AudioState::decodeFrame()
}
lock.unlock();
if(ret == AVERROR_EOF) break;
+ mMovie->mSendDataGood.clear(std::memory_order_relaxed);
+ mMovie->mSendCond.notify_one();
if(ret < 0)
{
std::cerr<< "Failed to decode frame: "<<ret <<std::endl;
@@ -1072,18 +1082,22 @@ int VideoState::handler()
int ret = avcodec_receive_frame(mCodecCtx, mDecodedFrame);
if(ret == AVERROR(EAGAIN))
{
+ mMovie->mSendDataGood.clear(std::memory_order_relaxed);
+ std::unique_lock<std::mutex>(mMovie->mSendMtx).unlock();
+ mMovie->mSendCond.notify_one();
do {
mQueueCond.wait(lock);
ret = avcodec_receive_frame(mCodecCtx, mDecodedFrame);
} while(ret == AVERROR(EAGAIN));
}
lock.unlock();
- if(ret == AVERROR_EOF)
- break;
+ if(ret == AVERROR_EOF) break;
+ mMovie->mSendDataGood.clear(std::memory_order_relaxed);
+ mMovie->mSendCond.notify_one();
if(ret < 0)
{
std::cerr<< "Failed to decode frame: "<<ret <<std::endl;
- break;
+ continue;
}
std::chrono::nanoseconds pts = synchronize(
@@ -1286,42 +1300,40 @@ int MovieState::parse_handler()
do {
/* Send whatever queued packets we have. */
- bool sent;
- do {
- sent = false;
- if(!audio_queue.empty())
- {
- std::unique_lock<std::mutex> lock(mAudio.mQueueMtx);
- int ret = avcodec_send_packet(mAudio.mCodecCtx, audio_queue.front());
- if(ret != AVERROR(EAGAIN))
- {
- lock.unlock();
- mAudio.mQueueCond.notify_one();
- audio_queue.pop();
- sent = true;
- }
- }
- if(!video_queue.empty())
- {
- std::unique_lock<std::mutex> lock(mVideo.mQueueMtx);
- int ret = avcodec_send_packet(mVideo.mCodecCtx, video_queue.front());
- if(ret != AVERROR(EAGAIN))
- {
- lock.unlock();
- mVideo.mQueueCond.notify_one();
- video_queue.pop();
- sent = true;
- }
- }
- } while(sent);
+ if(!audio_queue.empty())
+ {
+ std::unique_lock<std::mutex> lock(mAudio.mQueueMtx);
+ int ret;
+ do {
+ ret = avcodec_send_packet(mAudio.mCodecCtx, audio_queue.front());
+ if(ret != AVERROR(EAGAIN)) audio_queue.pop();
+ } while(ret != AVERROR(EAGAIN) && !audio_queue.empty());
+ lock.unlock();
+ mAudio.mQueueCond.notify_one();
+ }
+ if(!video_queue.empty())
+ {
+ std::unique_lock<std::mutex> lock(mVideo.mQueueMtx);
+ int ret;
+ do {
+ ret = avcodec_send_packet(mVideo.mCodecCtx, video_queue.front());
+ if(ret != AVERROR(EAGAIN)) video_queue.pop();
+ } while(ret != AVERROR(EAGAIN) && !video_queue.empty());
+ lock.unlock();
+ mVideo.mQueueCond.notify_one();
+ }
/* If the queues are completely empty, or it's not full and there's
* more input to read, go get more.
*/
size_t queue_size = audio_queue.totalSize() + video_queue.totalSize();
if(queue_size == 0 || (queue_size < MAX_QUEUE_SIZE && !input_finished))
break;
+
/* Nothing to send or get for now, wait a bit and try again. */
- std::this_thread::sleep_for(std::chrono::milliseconds(10));
+ { std::unique_lock<std::mutex> lock(mSendMtx);
+ if(mSendDataGood.test_and_set(std::memory_order_relaxed))
+ mSendCond.wait_for(lock, std::chrono::milliseconds(10));
+ }
} while(!mQuit.load(std::memory_order_relaxed));
}
/* Pass a null packet to finish the send buffers (the receive functions
--
cgit v1.2.3