#include <speex/speex.h>
#include <stdio.h>
/*The frame size in hardcoded for this sample code but it doesn’t have to be*/
#define     FRAME_SIZE 160
void write_wav_header(FILE *file, int rate, int channels)
{
   char ch[5];
   spx_int32_t itmp;
   spx_int16_t stmp;

   ch[4]=0;

   fprintf (file, "RIFF");

   itmp = 0x7fffffff;
   fwrite(&itmp, 4, 1, file);

   fprintf (file, "WAVEfmt ");

   itmp = 16;
   fwrite(&itmp, 4, 1, file);

   stmp = 1;
   fwrite(&stmp, 2, 1, file);

   stmp = channels;
   fwrite(&stmp, 2, 1, file);

   itmp = rate;
   fwrite(&itmp, 4, 1, file);

   itmp = rate*channels*2;
   fwrite(&itmp, 4, 1, file);

   stmp = 2*channels;
   fwrite(&stmp, 2, 1, file);

   stmp = 16;
   fwrite(&stmp, 2, 1, file);

   fprintf (file, "data");

   itmp = 0x7fffffff;
   fwrite(&itmp, 4, 1, file);

}

int main(int argc, char **argv)
{
    char *outFile,*inFile;
    FILE *fout,*fin;
    /*Holds the audio that will be written to file (16 bits per sample)*/
    short out[FRAME_SIZE];
    /*Speex handle samples as float, so we need an array of floats*/
    short output[FRAME_SIZE];
    char cbits[200];
    int nbBytes;
    /*Holds the state of the decoder*/
    void *state;
    /*Holds bits so they can be read and written to by the Speex routines*/
    SpeexBits bits;
    int i, tmp;
    /*Create a new decoder state in narrowband mode*/
    state = speex_decoder_init(&speex_nb_mode);
    /*Set the perceptual enhancement on*/
    tmp=0;
    speex_decoder_ctl(state, SPEEX_SET_ENH, &tmp);
    tmp=8;
    speex_encoder_ctl(state, SPEEX_SET_QUALITY, &tmp);
    inFile = argv[1];
    outFile = argv[2];
    fout = fopen(outFile, "w");
    fin = fopen(inFile, "r");
    /*Initialization of the structure that holds the bits*/
    speex_bits_init(&bits);
    
    /*******THIRU: WRITE WAV HEADER BACK******/

    write_wav_header(fout,8000,01);
    
    while (1)
    {
    /*Read the size encoded by sampleenc, this part will likely be
    different in your application*/
    fread(&nbBytes, sizeof(int), 1, fin);
    printf("Thiru1: Number of bytes of Read is %d\n",nbBytes);
    if (feof(fin))
    break;
    /*Read the "packet" encoded by sampleenc*/
    fread(cbits, 1, nbBytes, fin);
    //printf("Thiru2: value of nbBytes is %d\n",nbBytes);
    /*Copy the data into the bit-stream struct*/
    speex_bits_read_from(&bits, cbits, nbBytes);
    //printf("Thiru3: value of nbBytes is %d\n",nbBytes);
    /*Decode the data*/
    speex_decode_int(state, &bits, output);
    /*Copy from float to short (16 bits) for output*/
    for (i=0;i<FRAME_SIZE;i++)
    out[i]=output[i];
    /*Write the decoded audio to file*/
    fwrite(out, sizeof(short), FRAME_SIZE, fout);
    }
    /*Destroy the decoder state*/
    speex_decoder_destroy(state);
    /*Destroy the bit-stream truct*/
    speex_bits_destroy(&bits);
    fclose(fout);
    fclose(fin);
    return 0;
}