winamp/Src/nu/AudioOutput.h
2024-09-24 14:54:57 +02:00

389 lines
9.7 KiB
C++

#pragma once
#include <bfc/platform/types.h>
#include "../Winamp/in2.h"
#include "../Winamp/out.h"
#include "SpillBuffer.h"
#include <assert.h>
/* A class to manage Winamp input plugin audio output
** It handles the following for you:
** * Ensuring that Vis data is sent in chunks of 576
** * Dealing with gapless audio
** (you need to pass in the number of pre-delay and post-delay samples)
** * dealing with the DSP plugin
** * Waiting for CanWrite()
** * dealing with inter-timestamps
** e.g. you pass it >576 samples and it can give you a timestamp based on the divided chunk position
to use, you need to derive from a class that declares
int WaitOrAbort(int time_in_ms);
return 0 on success, non-zero when you need to abort. the return value is passed back through Write()
*/
namespace nu // namespace it since "AudioOutput" isn't a unique enough name
{
template <class wait_t>
class AudioOutput : public wait_t
{
public:
AudioOutput( In_Module *plugin ) : plugin( plugin )
{
Init( nullptr );
}
~AudioOutput()
{
post_buffer.reset();
buffer576.reset();
}
/* Initializes and sets the output plugin pointer
** for most input plugins, the nu::AudioOutput object will be a global,
** so this will be necessary to call at the start of Play thread */
void Init( Out_Module *_output )
{
output = _output;
audio_opened = false;
first_timestamp = 0;
sample_size = 0;
output_latency = 0;
post_buffer.reset();
buffer576.reset();
cut_size = 0;
pre_cut_size = 0;
pre_cut = 0;
decoder_delay = 0;
channels = 0;
sample_rate = 0;
bps = 0;
}
/* sets end-of-stream delay (in samples)
** WITHOUT componesating for post-delay.
** some filetypes (e.g. iTunes MP4) store gapless info this way */
void SetPostDelay(int postSize)
{
if (postSize < 0)
{
postSize = 0;
}
else if (postSize)
{
if (sample_size)
post_buffer.reserve(postSize*sample_size);
cut_size = postSize;
}
}
/* set end-of-stream zero padding, in samples
** compensates for decoder delay */
void SetZeroPadding(int postSize)
{
postSize -= decoder_delay;
if (postSize < 0)
{
postSize = 0;
}
SetPostDelay(postSize);
}
/* set decoder delay, initial zero samples and end-of-stream zero samples, all in one shot
** adjusts zero samples for decoder delay. call SetDelays() if your zero samples are already compensated */
void SetGapless(int decoderDelaySize, int preSize, int postSize)
{
decoder_delay = decoderDelaySize;
SetZeroPadding(postSize);
pre_cut_size = preSize;
pre_cut = pre_cut_size + decoder_delay;
}
/* set decoder delay, initial delay and end-of-stream delay, all in one shot
** WITHOUT componesating for post-delay.
** some filetypes (e.g. iTunes MP4) store gapless info this way */
void SetDelays(int decoderDelaySize, int preSize, int postSize)
{
decoder_delay = decoderDelaySize;
SetPostDelay(postSize);
pre_cut_size = preSize;
pre_cut = pre_cut_size;
}
/* Call on seek */
void Flush(int time_in_ms)
{
if (audio_opened)
{
pre_cut = pre_cut_size;
output->Flush(time_in_ms);
first_timestamp = 0; // once we've flushed, we should be accurate so no need for this anymore
buffer576.clear();
post_buffer.clear();
}
else
first_timestamp = time_in_ms;
}
bool Opened() const
{
return audio_opened;
}
int GetLatency() const
{
return output_latency;
}
int GetFirstTimestamp() const
{
return first_timestamp;
}
/* timestamp is meant to be the first timestamp according to the containing file format
** e.g. many MP4 videos start on 12ms or something, for accurate a/v syncing */
bool Open(int timestamp, int channels, int sample_rate, int bps, int buffer_len_ms=-1, int pre_buffer_ms=-1)
{
if (!audio_opened)
{
int latency = output->Open(sample_rate, channels, bps, buffer_len_ms, pre_buffer_ms);
if (latency < 0)
return false;
plugin->SAVSAInit(latency, sample_rate);
plugin->VSASetInfo(sample_rate, channels);
output->SetVolume(-666);
plugin->SetInfo(-1, sample_rate / 1000, channels, /* TODO? 0*/1);
output_latency = latency;
first_timestamp = timestamp;
sample_size = channels*bps / 8;
this->channels=channels;
this->sample_rate=sample_rate;
this->bps=bps;
SetPostDelay((int)cut_size); // set this again now that we know sample_size, so buffers get allocated correctly
buffer576.reserve(576*sample_size);
audio_opened=true;
}
return audio_opened;
}
void Close()
{
if (audio_opened && output)
{
output->Close();
plugin->SAVSADeInit();
}
output = 0;
first_timestamp = 0;
}
/* outSize is in bytes
** */
int Write(char *out, size_t outSize)
{
if (!out && !outSize)
{
/* --- write contents of buffered audio (end-zero-padding buffer) */
if (!post_buffer.empty())
{
void *buffer = 0;
size_t len = 0;
if (post_buffer.get(&buffer, &len))
{
int ret = Write576((char *)buffer, len);
if (ret != 0)
return ret;
}
}
/* --- write any remaining data in 576 spill buffer (skip vis) */
if (!buffer576.empty())
{
void *buffer = 0;
size_t len = 0;
if (buffer576.get(&buffer, &len))
{
int ret = WriteOutput((char *)buffer, len);
if (ret != 0)
return ret;
}
}
output->Write(0, 0);
return 0;
}
// this probably should not happen but have seen it in some crash reports
if (!sample_size)
return 0;
assert((outSize % sample_size) == 0);
size_t outSamples = outSize / sample_size;
/* --- cut pre samples, if necessary --- */
size_t pre = min(pre_cut, outSamples);
out += pre * sample_size;
outSize -= pre * sample_size;
pre_cut -= pre;
//outSize = outSamples * sample_size;
// do we will have samples to output after cutting pre-delay?
if (!outSize)
return 0;
/* --- if we don't have enough to fully fill the end-zero-padding buffer, go ahead and fill --- */
if (outSize < post_buffer.length())
{
size_t bytes_written = post_buffer.write(out, outSize);
out+=bytes_written;
outSize-=bytes_written;
}
// if we're out of samples, go ahead and bail
if (!outSize)
return 0;
/* --- write contents of buffered audio (end-zero-padding buffer) */
if (!post_buffer.empty())
{
void *buffer = 0;
size_t len = 0;
if (post_buffer.get(&buffer, &len))
{
int ret = Write576((char *)buffer, len);
if (ret != 0)
return ret;
}
}
/* --- make sure we have enough samples left over to fill our post-zero-padding buffer --- */
size_t remainingFill = /*cut_size - */post_buffer.remaining();
int outWrite = max(0, (int)outSize - (int)remainingFill);
/* --- write the output that doesn't end up in the post buffer */
if (outWrite)
{
int ret = Write576(out, outWrite);
if (ret != 0)
return ret;
}
out += outWrite;
outSize -= outWrite;
/* --- write whatever is left over into the end-zero-padding buffer --- */
if (outSize)
{
post_buffer.write(out, outSize);
}
return 0;
}
/* meant to be called after Write(0,0) */
int WaitWhilePlaying()
{
while (output->IsPlaying())
{
int ret = WaitOrAbort(10);
if (ret != 0)
return ret;
output->CanWrite(); // some output drivers need CanWrite
// to be called on a regular basis.
}
return 0;
}
private:
/* helper methods */
int WaitForOutput(int write_size_bytes)
{
while (output->CanWrite() < write_size_bytes)
{
int ret = WaitOrAbort(55);
if (ret != 0)
return ret;
}
return 0;
}
/* writes one chunk (576 samples) to the output plugin, waiting as necessary */
int WriteOutput(char *buffer, size_t len)
{
int ret = WaitForOutput((int)len);
if (ret != 0)
return ret;
// write vis data before so we guarantee 576 samples
if (len == 576*sample_size)
{
plugin->SAAddPCMData(buffer, channels, bps, output->GetWrittenTime() + first_timestamp);
plugin->VSAAddPCMData(buffer, channels, bps, output->GetWrittenTime() + first_timestamp);
}
if (plugin->dsp_isactive())
len = sample_size * plugin->dsp_dosamples((short *)buffer, (int)(len / sample_size), bps, channels, sample_rate);
output->Write(buffer, (int)len);
return 0;
}
/* given a large buffer, writes 576 sample chunks to the vis, dsp and output plugin */
int Write576(char *buffer, size_t out_size)
{
/* if we have some stuff leftover in the 576 sample spill buffer, fill it up */
if (!buffer576.empty())
{
size_t bytes_written = buffer576.write(buffer, out_size);
out_size -= bytes_written;
buffer += bytes_written;
}
if (buffer576.full())
{
void *buffer = 0;
size_t len = 0;
if (buffer576.get(&buffer, &len))
{
int ret = WriteOutput((char *)buffer, len);
if (ret != 0)
return ret;
}
}
while (out_size >= 576*sample_size)
{
int ret = WriteOutput(buffer, 576*sample_size);
if (ret != 0)
return ret;
out_size -= 576*sample_size;
buffer+=576*sample_size;
}
if (out_size)
{
assert(out_size < 576*sample_size);
buffer576.write(buffer, out_size);
}
return 0;
}
private:
Out_Module *output;
In_Module *plugin;
SpillBuffer post_buffer, buffer576;
size_t cut_size;
size_t pre_cut, pre_cut_size, decoder_delay;
bool audio_opened;
int first_timestamp; /* timestamp of the first decoded audio frame, necessary for accurate video syncing */
size_t sample_size; /* size, in bytes, of one sample of audio (channels*bps/8) */
int output_latency; /* as returned from Out_Module::Open() */
int channels, sample_rate, bps;
};
}