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-rw-r--r--akode/lib/wav_decoder.cpp236
1 files changed, 236 insertions, 0 deletions
diff --git a/akode/lib/wav_decoder.cpp b/akode/lib/wav_decoder.cpp
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+++ b/akode/lib/wav_decoder.cpp
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+/* aKode: Wav-Decoder
+
+ Copyright (C) 2004 Allan Sandfeld Jensen <kde@carewolf.com>
+
+ This library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public
+ License as published by the Free Software Foundation; either
+ version 2 of the License, or (at your option) any later version.
+
+ This library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public License
+ along with this library; see the file COPYING.LIB. If not, write to
+ the Free Software Foundation, Inc., 51 Franklin Steet, Fifth Floor,
+ Boston, MA 02110-1301, USA.
+*/
+
+#include <string.h>
+
+#include "audioframe.h"
+#include "decoder.h"
+#include "file.h"
+#include "wav_decoder.h"
+
+#include <iostream>
+
+namespace aKode {
+
+bool WavDecoderPlugin::canDecode(File* src) {
+ char header[4];
+ bool res = false;
+ src->openRO();
+ if (src->read(header, 4) != 4 || memcmp(header, "RIFF",4) != 0 ) goto close;
+ src->seek(8);
+ if (src->read(header, 4) != 4 || memcmp(header, "WAVE",4) != 0 ) goto close;
+ src->seek(20);
+ if (src->read(header, 2) != 2 || memcmp(header, "\x01\0",2) != 0 ) goto close;
+ res = true;
+close:
+ src->close();
+ return res;
+
+}
+
+extern "C" { WavDecoderPlugin wav_decoder; }
+
+struct WavDecoder::private_data
+{
+ private_data() : valid(false), buffer_length(0), buffer(0) {};
+ AudioConfiguration config;
+ bool valid;
+ long position;
+
+ long pos;
+ long length;
+
+ unsigned int buffer_length;
+ unsigned char *buffer;
+
+ File *src;
+};
+
+
+WavDecoder::WavDecoder(File *src) {
+ d = new private_data;
+
+ openFile(src);
+}
+
+bool WavDecoder::openFile(File* src) {
+ d->src = src;
+ src->openRO();
+ src->fadvise();
+
+ // Get format information
+ unsigned char buffer[4];
+ src->seek(4);
+ src->read((char*)buffer, 4); // size of stream
+ d->length = buffer[0] + buffer[1]*256 + buffer[2] * (1<<16) + buffer[3] * (1<<24) + 8;
+
+ src->seek(16);
+ src->read((char*)buffer, 4); // should really be 16
+ d->pos = 20 + buffer[0] + buffer[1]*256;
+ if (buffer[2] != 0 || buffer[3] != 0) goto invalid;
+
+ src->read((char*)buffer, 2); // check for compression
+ if (*(short*)buffer != 1) goto invalid;
+
+ src->read((char*)buffer, 2);
+ d->config.channels = buffer[0] + buffer[1]*256;
+ if (d->config.channels <=2)
+ d->config.channel_config = MonoStereo;
+ else
+ d->config.channel_config = MultiChannel;
+
+ src->read((char*)buffer, 4);
+ d->config.sample_rate = buffer[0] + buffer[1]*256 + buffer[2] * (1<<16) + buffer[3] * (1<<24);
+
+ src->seek(34);
+ src->read((char*)buffer, 2);
+ d->config.sample_width = buffer[0] + buffer[1]*256;
+
+ // Various sanity checks
+ if (d->config.sample_width != 8 && d->config.sample_width != 16 && d->config.sample_width != 32) goto invalid;
+ if (d->config.sample_rate > 200000) goto invalid;
+
+find_data:
+ src->seek(d->pos);
+ src->read((char*)buffer, 4);
+ if (memcmp(buffer, "data", 4) != 0)
+ if (memcmp(buffer, "clm ", 4) != 0)
+ goto invalid;
+ else {
+ src->read((char*)buffer, 4);
+ d->pos = d->pos+ 8 + buffer[0] + buffer[1]*256;
+ goto find_data;
+ }
+
+ src->seek(d->pos+8); // start of data
+ d->position = 0;
+ d->valid = true;
+ // 1024 samples:
+ d->buffer_length = 1024*((d->config.sample_width+7)/8)*d->config.channels;
+ d->buffer = new unsigned char[d->buffer_length];
+ return true;
+
+invalid:
+ std::cerr << "Invalid WAV file\n";
+ d->valid = false;
+ src->close();
+ return false;
+}
+
+void WavDecoder::close() {
+ d->src->close();
+ delete[] d->buffer;
+ d->valid = false;
+}
+
+WavDecoder::~WavDecoder() {
+ delete d;
+}
+
+bool WavDecoder::readFrame(AudioFrame* frame)
+{
+ if (!d->valid || eof()) return false;
+
+ unsigned long samples = 1024;
+ // read a frame
+ unsigned long length;
+ length = d->src->read((char*)d->buffer, d->buffer_length);
+ if (length != d->buffer_length) {
+ samples = length / (d->config.channels * ((d->config.sample_width+7)/8));
+ }
+ d->pos += length;
+ d->position += samples;
+ // Ensure the frame is properly configured
+ frame->reserveSpace(&d->config, samples);
+
+ int channels = d->config.channels;
+ if (d->config.sample_width == 8) {
+ // WAV 8bit is unsigned
+ uint8_t* buffer = (uint8_t*)d->buffer;
+ int8_t** data = (int8_t**)frame->data;
+ for(unsigned int i=0; i<samples; i++)
+ for(int j=0; j<channels; j++)
+ data[j][i] = (int(buffer[i*channels+j])) - 128;
+ }
+ else
+ if (d->config.sample_width == 16) {
+ int16_t* buffer = (int16_t*)d->buffer;
+ int16_t** data = (int16_t**)frame->data;
+ for(unsigned int i=0; i<samples; i++)
+ for(int j=0; j<channels; j++)
+ data[j][i] = buffer[i*channels+j];
+ } else
+ if (d->config.sample_width == 32) {
+ int32_t* buffer = (int32_t*)d->buffer;
+ int32_t** data = (int32_t**)frame->data;
+ for(unsigned int i=0; i<samples; i++)
+ for(int j=0; j<channels; j++)
+ data[j][i] = buffer[i*channels+j];
+ } else
+ return false;
+
+ frame->pos = position();
+
+ return true;
+}
+
+long WavDecoder::length() {
+ if (!d->valid) return -1;
+ long byterate = d->config.sample_rate * d->config.channels * ((d->config.sample_width+7)/8);
+ return (d->length-44)/byterate;
+}
+
+long WavDecoder::position() {
+ if (!d->valid) return -1;
+ long div = (d->position / d->config.sample_rate) * 1000;
+ long rem = (d->position % d->config.sample_rate) * 1000;
+ return div + (rem / d->config.sample_rate);
+}
+
+bool WavDecoder::eof() {
+ if (!d->src) return true;
+ else return d->src->eof();
+}
+
+bool WavDecoder::error() {
+ return !d->valid;
+}
+
+bool WavDecoder::seek(long pos) {
+ int samplesize = d->config.channels * ((d->config.sample_width+7)/8);
+ long byterate = d->config.sample_rate * samplesize;
+ long sample_pos = (pos * byterate) / 1000;
+ long byte_pos = sample_pos * samplesize;
+ if (byte_pos+44 >= d->length) return false;
+ if (!d->src->seek(byte_pos+44)) return false;
+ d->pos = byte_pos + 44;
+ return true;
+}
+
+bool WavDecoder::seekable() {
+ return d->src->seekable();
+}
+
+const AudioConfiguration* WavDecoder::audioConfiguration() {
+ if (!d->valid) return 0;
+ return &d->config;
+}
+
+} // namespace
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