nivedita velagaleti / Mbed 2 deprecated lab3_musicplayer

music main

Dependencies:   USBHost mbed

Fork of AppBoard_Waveplayer by jim hamblen

WaveFileReader.h@11:e48cb1e38995, 2015-04-14 (annotated)

Committer:
niv17
Date:
Tue Apr 14 03:46:33 2015 +0000
Revision:
11:e48cb1e38995
Version that needs to be fixed

Who changed what in which revision?

UserRevisionLine numberNew contents of line
niv17 11:e48cb1e38995 1 /* Read the wavefile */
niv17 11:e48cb1e38995 2
niv17 11:e48cb1e38995 3 typedef struct uFMT_STRUCT {
niv17 11:e48cb1e38995 4 short comp_code;
niv17 11:e48cb1e38995 5 short num_channels;
niv17 11:e48cb1e38995 6 unsigned sample_rate;
niv17 11:e48cb1e38995 7 unsigned avg_Bps;
niv17 11:e48cb1e38995 8 short block_align;
niv17 11:e48cb1e38995 9 short sig_bps;
niv17 11:e48cb1e38995 10 } FMT_STRUCT;
niv17 11:e48cb1e38995 11
niv17 11:e48cb1e38995 12 class WaveFileReader {
niv17 11:e48cb1e38995 13
niv17 11:e48cb1e38995 14 private:
niv17 11:e48cb1e38995 15 FILE * wavefile;
niv17 11:e48cb1e38995 16 bool isRepeat;
niv17 11:e48cb1e38995 17 unsigned dataChunkSize;
niv17 11:e48cb1e38995 18 long int startofdata;
niv17 11:e48cb1e38995 19 void readHeader();
niv17 11:e48cb1e38995 20 FMT_STRUCT wav_format;
niv17 11:e48cb1e38995 21
niv17 11:e48cb1e38995 22 public:
niv17 11:e48cb1e38995 23 WaveFileReader( FILE *, bool);
niv17 11:e48cb1e38995 24 float readSamplePeriod();
niv17 11:e48cb1e38995 25 size_t read(unsigned short *buf, size_t size);
niv17 11:e48cb1e38995 26 };
niv17 11:e48cb1e38995 27
niv17 11:e48cb1e38995 28 WaveFileReader::WaveFileReader(FILE *wavefile, bool isRepeat){
niv17 11:e48cb1e38995 29 this->wavefile = wavefile;
niv17 11:e48cb1e38995 30 this->isRepeat = isRepeat;
niv17 11:e48cb1e38995 31 readHeader();
niv17 11:e48cb1e38995 32 }
niv17 11:e48cb1e38995 33
niv17 11:e48cb1e38995 34 float WaveFileReader::readSamplePeriod(){
niv17 11:e48cb1e38995 35 return 1000000/(wav_format.sample_rate);
niv17 11:e48cb1e38995 36 }
niv17 11:e48cb1e38995 37
niv17 11:e48cb1e38995 38 void WaveFileReader::readHeader(){
niv17 11:e48cb1e38995 39 unsigned chunk_id, data, chunk_size;
niv17 11:e48cb1e38995 40 fread(&chunk_id,4,1,wavefile);
niv17 11:e48cb1e38995 41 fread(&chunk_size,4,1,wavefile);
niv17 11:e48cb1e38995 42
niv17 11:e48cb1e38995 43 while (!feof(wavefile)){
niv17 11:e48cb1e38995 44 switch (chunk_id) {
niv17 11:e48cb1e38995 45 case 0x46464952:
niv17 11:e48cb1e38995 46 fread(&data,4,1,wavefile);
niv17 11:e48cb1e38995 47 break;
niv17 11:e48cb1e38995 48 case 0x20746d66:
niv17 11:e48cb1e38995 49 fread(&wav_format,sizeof(wav_format),1,wavefile);
niv17 11:e48cb1e38995 50 if (chunk_size > sizeof(wav_format))
niv17 11:e48cb1e38995 51 fseek(wavefile,chunk_size-sizeof(wav_format),SEEK_CUR);
niv17 11:e48cb1e38995 52 break;
niv17 11:e48cb1e38995 53 case 0x5453494c:
niv17 11:e48cb1e38995 54 fseek(wavefile,chunk_size,SEEK_CUR);
niv17 11:e48cb1e38995 55 break;
niv17 11:e48cb1e38995 56 case 0x61746164:
niv17 11:e48cb1e38995 57 startofdata = ftell(wavefile);
niv17 11:e48cb1e38995 58 dataChunkSize = chunk_size;
niv17 11:e48cb1e38995 59 fseek(wavefile,chunk_size,SEEK_CUR);
niv17 11:e48cb1e38995 60 break;
niv17 11:e48cb1e38995 61 default:
niv17 11:e48cb1e38995 62 data=fseek(wavefile,chunk_size,SEEK_CUR);
niv17 11:e48cb1e38995 63 break;
niv17 11:e48cb1e38995 64 }
niv17 11:e48cb1e38995 65 fread(&chunk_id,4,1,wavefile);
niv17 11:e48cb1e38995 66 fread(&chunk_size,4,1,wavefile);
niv17 11:e48cb1e38995 67 }
niv17 11:e48cb1e38995 68 fseek(wavefile,startofdata,SEEK_SET);
niv17 11:e48cb1e38995 69 }
niv17 11:e48cb1e38995 70
niv17 11:e48cb1e38995 71 size_t WaveFileReader::read(unsigned short *DAC_fifo, size_t size){
niv17 11:e48cb1e38995 72 unsigned channel;
niv17 11:e48cb1e38995 73 short unsigned dac_data;
niv17 11:e48cb1e38995 74 long long slice_value;
niv17 11:e48cb1e38995 75 char *slice_buf;
niv17 11:e48cb1e38995 76 short *data_sptr;
niv17 11:e48cb1e38995 77 unsigned char *data_bptr;
niv17 11:e48cb1e38995 78 int *data_wptr;
niv17 11:e48cb1e38995 79
niv17 11:e48cb1e38995 80 slice_buf=(char *)malloc(wav_format.block_align);
niv17 11:e48cb1e38995 81 if (!slice_buf) {
niv17 11:e48cb1e38995 82 printf("Unable to malloc slice buffer");
niv17 11:e48cb1e38995 83 exit(1);
niv17 11:e48cb1e38995 84 }
niv17 11:e48cb1e38995 85
niv17 11:e48cb1e38995 86 for (size_t i=0; i<size; i++){
niv17 11:e48cb1e38995 87 fread(slice_buf,wav_format.block_align,1,wavefile);
niv17 11:e48cb1e38995 88 if (feof(wavefile)) {
niv17 11:e48cb1e38995 89 if(isRepeat){
niv17 11:e48cb1e38995 90 fseek(wavefile,startofdata,SEEK_SET);
niv17 11:e48cb1e38995 91 printf("Reached end of file, reapeat is on");
niv17 11:e48cb1e38995 92 }else{
niv17 11:e48cb1e38995 93 printf("Reached end of file, reapeat is off");
niv17 11:e48cb1e38995 94 return i;
niv17 11:e48cb1e38995 95 }
niv17 11:e48cb1e38995 96 }
niv17 11:e48cb1e38995 97 data_sptr=(short *)slice_buf; // 16 bit samples
niv17 11:e48cb1e38995 98 data_bptr=(unsigned char *)slice_buf; // 8 bit samples
niv17 11:e48cb1e38995 99 data_wptr=(int *)slice_buf; // 32 bit samples
niv17 11:e48cb1e38995 100 slice_value=0;
niv17 11:e48cb1e38995 101 for (channel=0;channel<wav_format.num_channels;channel++) {
niv17 11:e48cb1e38995 102 switch (wav_format.sig_bps) {
niv17 11:e48cb1e38995 103 case 16:
niv17 11:e48cb1e38995 104 slice_value+=data_sptr[channel];
niv17 11:e48cb1e38995 105 break;
niv17 11:e48cb1e38995 106 case 32:
niv17 11:e48cb1e38995 107 slice_value+=data_wptr[channel];
niv17 11:e48cb1e38995 108 break;
niv17 11:e48cb1e38995 109 case 8:
niv17 11:e48cb1e38995 110 slice_value+=data_bptr[channel];
niv17 11:e48cb1e38995 111 break;
niv17 11:e48cb1e38995 112 }
niv17 11:e48cb1e38995 113 }
niv17 11:e48cb1e38995 114 slice_value/=wav_format.num_channels;
niv17 11:e48cb1e38995 115 switch (wav_format.sig_bps) {
niv17 11:e48cb1e38995 116 case 8:
niv17 11:e48cb1e38995 117 slice_value<<=8;
niv17 11:e48cb1e38995 118 break;
niv17 11:e48cb1e38995 119 case 16:
niv17 11:e48cb1e38995 120 slice_value+=32768;
niv17 11:e48cb1e38995 121 break;
niv17 11:e48cb1e38995 122 case 32:
niv17 11:e48cb1e38995 123 slice_value>>=16;
niv17 11:e48cb1e38995 124 slice_value+=32768;
niv17 11:e48cb1e38995 125 break;
niv17 11:e48cb1e38995 126 }
niv17 11:e48cb1e38995 127 dac_data=(short unsigned)slice_value;
niv17 11:e48cb1e38995 128 DAC_fifo[i]=dac_data;
niv17 11:e48cb1e38995 129 }
niv17 11:e48cb1e38995 130 free(slice_buf);
niv17 11:e48cb1e38995 131 return size;
niv17 11:e48cb1e38995 132 }