test/wav.cpp

   1 /* ------------------------------------------------------------------
   2  * Copyright (C) 2009 Martin Storsjo
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *      http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
  13  * express or implied.
  14  * See the License for the specific language governing permissions
  15  * and limitations under the License.
  16  * -------------------------------------------------------------------
  17  */
  18
  19 #include "wav.h"
  20
  21 void WavWriter::writeString(const char *str) {
  22         fputc(str[0], wav);
  23         fputc(str[1], wav);
  24         fputc(str[2], wav);
  25         fputc(str[3], wav);
  26 }
  27
  28 void WavWriter::writeInt32(int value) {
  29         fputc((value >>  0) & 0xff, wav);
  30         fputc((value >>  8) & 0xff, wav);
  31         fputc((value >> 16) & 0xff, wav);
  32         fputc((value >> 24) & 0xff, wav);
  33 }
  34
  35 void WavWriter::writeInt16(int value) {
  36         fputc((value >> 0) & 0xff, wav);
  37         fputc((value >> 8) & 0xff, wav);
  38 }
  39
  40 void WavWriter::writeHeader(int length) {
  41         writeString("RIFF");
  42         writeInt32(4 + 8 + 16 + 8 + length);
  43         writeString("WAVE");
  44
  45         writeString("fmt ");
  46         writeInt32(16);
  47
  48         int bytesPerFrame = bitsPerSample/8*channels;
  49         int bytesPerSec = bytesPerFrame*sampleRate;
  50         writeInt16(1);             // Format
  51         writeInt16(channels);      // Channels
  52         writeInt32(sampleRate);    // Samplerate
  53         writeInt32(bytesPerSec);   // Bytes per sec
  54         writeInt16(bytesPerFrame); // Bytes per frame
  55         writeInt16(bitsPerSample); // Bits per sample
  56
  57         writeString("data");
  58         writeInt32(length);
  59 }
  60
  61 WavWriter::WavWriter(const char *filename, int sampleRate, int bitsPerSample, int channels) {
  62         wav = fopen(filename, "wb");
  63         if (wav == NULL)
  64                 return;
  65         dataLength = 0;
  66         this->sampleRate = sampleRate;
  67         this->bitsPerSample = bitsPerSample;
  68         this->channels = channels;
  69
  70         writeHeader(dataLength);
  71 }
  72
  73 WavWriter::~WavWriter() {
  74         if (wav == NULL)
  75                 return;
  76         fseek(wav, 0, SEEK_SET);
  77         writeHeader(dataLength);
  78         fclose(wav);
  79 }
  80
  81 void WavWriter::writeData(const unsigned char* data, int length) {
  82         if (wav == NULL)
  83                 return;
  84         fwrite(data, length, 1, wav);
  85         dataLength += length;
  86 }
  87