C Programming-read dat data and convert it to a WAV file

Dat data format 5A 5A 5A xx (frame header) the frame header is followed by the first ad Channel 1 data (2 bytes), the second Ad Channel 1 data (2 bytes), and the first ad Channel 2 data (2 bytes ), the second AD Channel 2 data (2 bytes ),......... The first ad Channel 6 data (2 byte) and the second Ad Channel 6 data (2 byte ). I extracted the first ad Channel 6 data. Then convert it to 16 bit, and then-32768 to positive and negative signals, because ad collects 0-5 V signals, minus 32768 to convert it to-2.5 V ~ + 2.5 V. Then, write the wav file into the wav file according to the wav file structure.

Http://download.csdn.net/source/2206332 code and DAT files.

# Include <stdio. h> <br/> # include <stdlib. h> </P> <p> # define size 1300*1024 <br/> # define SPS 8000 </P> <p> typedef struct twav_header <br/> {<br //> // riff wave chunk, 12 bytes <br/> unsigned char riff [4]; <br/> unsigned int dwfilesize; <br/> unsigned char wave [4]; </P> <p> // format chunk, 24 bytes <br/> unsigned char FMT [4]; <br/> unsigned int dwchunksize; <br/> unsigned short wcompress; <br/> unsigned short wchannelnum; <br/> unsigned int dwsamplerate; <br/> unsigned int dwbytepersec; <br/> unsigned short wblockal; <br/> unsigned short wbitspersample; </P> <p> // data chunk, 8 bytes <br/> unsigned char data [4]; <br/> unsigned int dwdatasize; <br/>} wav_header; </P> <p> char riff [4] = {'R', 'I ', 'F', 'F'}; <br/> char WAV [4] = {'w', 'A', 'V', 'E '}; <br/> char FMT [4] = {'F', 'M', 't', 0x20 }; <br/> char data [4] = {'D', 'A', 't', 'A'}; </P> <p> int main () <br/>{ <br/> wav_header wavhead; <br/> file * FP; <br/> file * fpoutwav; <br/> file * fpoutdat; <br/> char infile [20], outfilewav [20], outfiledat [20]; <br/> unsigned char * pbuffer; <br/> unsigned short * pwbuffer; <br/> unsigned short * pwnobuffer; <br/> unsigned short * pwnormbuffer; // normalized data buffer <br/> int I, CNT, channelno; </P> <p> pbuffer = (unsigned char *) malloc (size * sizeof (unsigned char); <br/> memset (pbuffer, 0, size ); </P> <p> pwbuffer = (unsigned short *) malloc (size/2) * sizeof (unsigned short); <br/> memset (pbuffer, 0, (size/2) * sizeof (unsigned short); </P> <p> pwnobuffer = (unsigned short *) malloc (size/12) * sizeof (unsigned short); <br/> memset (pwnobuffer, 0, (size/12) * sizeof (unsigned short )); </P> <p> pwnormbuffer = (unsigned short *) malloc (size/12) * sizeof (unsigned short); <br/> memset (pwnormbuffer, 0, (size/12) * sizeof (unsigned short); </P> <p> puts ("input file name (DAT ):"); <br/> gets (infile); <br/> puts ("output file name (WAV):"); <br/> gets (outfilewav ); <br/> puts ("output file name (DAT):"); <br/> gets (outfiledat); <br/> puts ("channel NO (1-12): "); <br/> scanf (" % d ", & channelno); </P> <p> If (FP = fopen (infile," rb ")) = NULL) <br/>{< br/> printf ("cannot open file: % s/n", infile); <br/> system ("pause "); <br/> return 0; <br/>}< br/> fseek (FP, 0l, seek_set); <br/> fread (pbuffer, 1, size, FP ); </P> <p> for (I = 0; I <100; I ++) <br/> printf ("% x", * (pbuffer + I )); </P> <p> // extract channel channelno data <br/> CNT = 0; <br/> for (I = 0; I <size-36; I ++) <br/> If (pbuffer [I] = 0xff) & (pbuffer [I + 1] = 0x5a) & (pbuffer [I + 2] = 0x5a) & (pbuffer [I + 3] = 0x5a )) <br/> pwnobuffer [CNT ++] = pbuffer [I + 4 + 2 * (channelno-1)] * 256 + pbuffer [I + 4 + 2 * (channelno-1) + 1]; </P> <p> for (I = 0; I <5; I ++) <br/> printf ("/n % x % d ", * (pwnobuffer + I), CNT); </P> <p> // normalize the data, (data-32768) <br/> for (I = 0; <CNT; I ++) <br/> pwnormbuffer [I] = pwnobuffer [I]-32768; </P> <p> // initialize the wav file header <br/> memcpy (wavhead. riff, Riff, 4); <br/> wavhead. dwfilesize = CNT * 2 + sizeof (wav_header)-8; <br/> memcpy (wavhead. wave, WAV, 4); <br/> memcpy (wavhead. FMT, FMT, 4); <br/> wavhead. dwchunksize = 0x10; <br/> wavhead. wcompress = 1; <br/> wavhead. wchannelnum = 1; <br/> wavhead. dwsamplerate = SPS; <br/> wavhead. dwbytepersec = 2 * SPS; <br/> wavhead. wblockalign = 2; <br/> wavhead. wbitspersample = 16; <br/> memcpy (wavhead. data, data, 4); <br/> wavhead. dwdatasize = CNT * 2; </P> <p> // write the data into WAV file <br/> If (fpoutwav = fopen (outfilewav, "WB ")) = NULL) <br/>{< br/> printf ("cannot open file: % s/n", outfilewav); <br/> system ("pause "); <br/> return 0; <br/>}</P> <p> fwrite (& wavhead, sizeof (wav_header), 1, fpoutwav ); <br/> fwrite (pwnormbuffer, sizeof (unsigned short), CNT, fpoutwav ); </P> <p> // write the data into DAT file <br/> If (fpoutdat = fopen (outfiledat, "WB") = NULL) <br/>{< br/> printf ("cannot open file: % s/n", outfiledat); <br/> system ("pause "); <br/> return 0; <br/>}</P> <p> fwrite (pwnobuffer, sizeof (unsigned short), CNT, fpoutdat ); </P> <p> fclose (FP); fclose (fpoutwav); fclose (fpoutdat); <br/> free (pbuffer); free (pwbuffer ); free (pwnobuffer); <br/> system ("pause"); <br/> return 0; <br/>}< br/>