Aegisub/core/audio_provider_stream.cpp
Rodrigo Braz Monteiro 41a4cd3c2c Preparations for audio scrubbing
Originally committed to SVN as r459.
2006-07-04 05:10:29 +00:00

131 lines
3.5 KiB
C++

// Copyright (c) 2006, Rodrigo Braz Monteiro
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
// * Neither the name of the Aegisub Group nor the names of its contributors
// may be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// -----------------------------------------------------------------------------
//
// AEGISUB
//
// Website: http://aegisub.cellosoft.com
// Contact: mailto:zeratul@cellosoft.com
//
///////////
// Headers
#include "audio_provider_stream.h"
#include "utils.h"
///////////////
// Constructor
StreamAudioProvider::StreamAudioProvider() {
bufLen = 8192;
startPos = 0;
endPos = 8192;
}
//////////////
// Destructor
StreamAudioProvider::~StreamAudioProvider() {
for (std::list<BufferChunk*>::iterator cur=buffer.begin();cur!=buffer.end();cur++) {
delete *cur;
}
buffer.clear();
}
/////////////
// Get audio
void StreamAudioProvider::GetAudio(void *buf, __int64 start, __int64 count) {
// Write
__int64 left = count;
__int64 written = 0;
int toWrite;
while (left > 0) {
// Discard done
if (startPos == 8192) {
buffer.pop_front();
startPos = 0;
}
// Is last?
bool isLast = buffer.size() == 1;
int size = 8192;
if (isLast) size = endPos;
// Write
toWrite = MIN(int(size-startPos),int(left));
memcpy(((short*)buf)+written,&(buffer.front()->buf[startPos]),toWrite);
startPos += toWrite;
written += toWrite;
left -= toWrite;
// Last
if (isLast) break;
}
// Still left, fill with zero
if (left > 0) {
short *dst = (short*) buf;
for (__int64 i=written;i<count;i++) {
dst[i] = 0;
}
}
}
//////////////////////////
// Append audio to stream
void StreamAudioProvider::Append(void *src, __int64 count) {
// Read
__int64 left = count;
__int64 read = 0;
int toRead;
while (left > 0) {
// Check space
if (endPos == 8192) {
buffer.push_back(new BufferChunk);
endPos = 0;
}
// Read
toRead = MIN(int(8192-endPos),int(left));
memcpy(&(buffer.back()->buf[endPos]),((short*)src)+read,toRead);
endPos += toRead;
read += toRead;
left -= toRead;
}
}
////////////////////////////
// Buffer chunk constructor
StreamAudioProvider::BufferChunk::BufferChunk() {
buf.resize(4096);
isFree = true;
}