Diff: wavfile.c

Revision:

1:90c01826cdb8

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wavfile.c	Tue Dec 08 00:45:23 2015 +0000
@@ -0,0 +1,83 @@
+/*
+A simple sound library for CSE 20211 by Douglas Thain
+For course assignments, you should not change this file.
+For complete documentation, see:
+http://www.nd.edu/~dthain/courses/cse20211/fall2013/wavfile
+*/
+
+#include "wavfile.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct wavfile_header {
+    char    riff_tag[4];
+    int riff_length;
+    char    wave_tag[4];
+    char    fmt_tag[4];
+    int fmt_length;
+    short   audio_format;
+    short   num_channels;
+    int sample_rate;
+    int byte_rate;
+    short   block_align;
+    short   bits_per_sample;
+    char    data_tag[4];
+    int data_length;
+};
+
+FILE * wavfile_open( const char *filename )
+{
+    
+    struct wavfile_header header;
+
+    int samples_per_second = WAVFILE_SAMPLES_PER_SECOND;
+    int bits_per_sample = 16;
+
+    strncpy(header.riff_tag,"RIFF",4);
+    strncpy(header.wave_tag,"WAVE",4);
+    strncpy(header.fmt_tag,"fmt ",4);
+    strncpy(header.data_tag,"data",4);
+
+    header.riff_length = 0;
+    header.fmt_length = 16;
+    header.audio_format = 1;
+    header.num_channels = 1;
+    header.sample_rate = samples_per_second;
+    header.byte_rate = samples_per_second*(bits_per_sample/8);
+    header.block_align = bits_per_sample/8;
+    header.bits_per_sample = bits_per_sample;
+    header.data_length = 0;
+
+
+    FILE * file = fopen(filename,"w");
+    if(!file) return 0;
+
+    fwrite(&header,sizeof(header),1,file);
+
+    fflush(file);
+
+    return file;
+
+}
+
+void wavfile_write( FILE *file, short data[], int length )
+{
+    fwrite(data,sizeof(short),length,file);
+}
+
+void wavfile_close( FILE *file )
+{
+    int file_length = ftell(file);
+
+    int data_length = file_length - sizeof(struct wavfile_header);
+    fseek(file,sizeof(struct wavfile_header) - sizeof(int),SEEK_SET);
+    fwrite(&data_length,sizeof(data_length),1,file);
+
+    int riff_length = file_length - 8;
+    fseek(file,4,SEEK_SET);
+    fwrite(&riff_length,sizeof(riff_length),1,file);
+
+    fclose(file);
+}