Aegisub/aegisub/libmedia/cache/audio_ram.cpp

175 lines
5 KiB
C++

// Copyright (c) 2005-2006, Rodrigo Braz Monteiro, Fredrik Mellbin
// 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 Project http://www.aegisub.org/
//
// $Id$
/// @file audio_provider_ram.cpp
/// @brief Caching audio provider using heap memory for backing
/// @ingroup audio_input
///
#include "config.h"
#include "audio_provider_ram.h"
#include "dialog_progress.h"
#include "frame_main.h"
#include "main.h"
#include "utils.h"
/// DOCME
#define CacheBits ((22))
/// DOCME
#define CacheBlockSize ((1 << CacheBits))
/// @brief Constructor
/// @param source
///
RAMAudioProvider::RAMAudioProvider(AudioProvider *src) {
std::auto_ptr<AudioProvider> source(src);
// Init
blockcache = NULL;
blockcount = 0;
samples_native_endian = source->AreSamplesNativeEndian();
// Allocate cache
int64_t ssize = source->GetNumSamples() * source->GetBytesPerSample();
blockcount = (ssize + CacheBlockSize - 1) >> CacheBits;
blockcache = new char*[blockcount];
for (int i = 0; i < blockcount; i++) {
blockcache[i] = NULL;
}
// Allocate cache blocks
try {
for (int i = 0; i < blockcount; i++) {
blockcache[i] = new char[std::min<size_t>(CacheBlockSize,ssize-i*CacheBlockSize)];
}
}
catch (...) {
Clear();
throw AudioOpenError("Couldn't open audio, not enough ram available.");
}
// Copy parameters
bytes_per_sample = source->GetBytesPerSample();
num_samples = source->GetNumSamples();
channels = source->GetChannels();
sample_rate = source->GetSampleRate();
filename = source->GetFilename();
// Start progress
volatile bool canceled = false;
DialogProgress *progress = new DialogProgress(AegisubApp::Get()->frame,_("Load audio"),&canceled,_("Reading into RAM"),0,source->GetNumSamples());
progress->Show();
progress->SetProgress(0,1);
// Read cache
int readsize = CacheBlockSize / source->GetBytesPerSample();
for (int i=0;i<blockcount && !canceled; i++) {
source->GetAudio((char*)blockcache[i],i*readsize, i == blockcount-1 ? (source->GetNumSamples() - i*readsize) : readsize);
progress->SetProgress(i,blockcount-1);
}
// Clean up progress
if (canceled) {
Clear();
throw agi::UserCancelException("Audio loading cancelled by user");
}
progress->Destroy();
}
/// @brief Destructor
///
RAMAudioProvider::~RAMAudioProvider() {
Clear();
}
/// @brief Clear
///
void RAMAudioProvider::Clear() {
// Free ram cache
if (blockcache) {
for (int i = 0; i < blockcount; i++) {
delete [] blockcache[i];
}
delete [] blockcache;
}
blockcache = NULL;
blockcount = 0;
}
/// @brief Get audio
/// @param buf
/// @param start
/// @param count
///
void RAMAudioProvider::GetAudio(void *buf, int64_t start, int64_t count) const {
// Requested beyond the length of audio
if (start+count > num_samples) {
int64_t oldcount = count;
count = num_samples-start;
if (count < 0) count = 0;
// Fill beyond with zero
if (bytes_per_sample == 1) {
char *temp = (char *) buf;
for (int i=count;i<oldcount;i++) {
temp[i] = 0;
}
}
if (bytes_per_sample == 2) {
short *temp = (short *) buf;
for (int i=count;i<oldcount;i++) {
temp[i] = 0;
}
}
}
if (count) {
// Prepare copy
char *charbuf = (char *)buf;
int i = (start*bytes_per_sample) >> CacheBits;
int start_offset = (start*bytes_per_sample) & (CacheBlockSize-1);
int64_t bytesremaining = count*bytes_per_sample;
// Copy
while (bytesremaining) {
int readsize = std::min<int>(bytesremaining, CacheBlockSize - start_offset);
memcpy(charbuf,(char *)(blockcache[i++]+start_offset),readsize);
charbuf+=readsize;
start_offset=0;
bytesremaining-=readsize;
}
}
}