int main(int argc, char **argv)
{
struct holder holder = {};
if (argc < 2)
errx(1, "bad arguments");
open_io(&holder, argv[1]);
holder.samples_count = holder.ininfo.samplerate / 100;
/* do we have enough data? no = clamp the graph */
if (holder.width > holder.samples_count / 2)
holder.width = holder.samples_count / 2;
prepare_fftw(&holder);
decode(&holder);
destroy_fftw(&holder);
close_io(&holder);
return 0;
}
/*
* Main loop continuously reads/writes from input/output, downsampleing as we go.
* input: data inputinformation
* output: data output information
* downsample_factor how much to downsample by (usually 4)
* overlap: how many samples to overlap between subsequent samples
*/
int main_loop(catalyzer_io * input,
catalyzer_io * output,
int downsample_factor,
int sample_size,
int overlap) {
if (sample_size % downsample_factor) {
fprintf(stderr,"downsample factor does not evenly divide sample size.\n");
return -1;
}
int input_overlap = overlap * downsample_factor * 2;
int output_overlap = overlap * 2;
int input_buffer_size = sample_size + input_overlap;
int output_buffer_size = sample_size / downsample_factor + output_overlap;
int * input_buffer = calloc(input_buffer_size, sizeof(int));
int * output_buffer = calloc(output_buffer_size, sizeof(int));
catalyzer_fftw_state * fftw_state = prepare_fftw(input_buffer_size, output_buffer_size);
for (;;) {
/* Copy some data from the tail of the input buffer to the begining,
* as per overlap requirements
*/
memmove(input_buffer,
input_buffer+ (input_buffer_size - input_overlap) * sizeof(int),
input_overlap * sizeof(int));
/* Read input data */
cat_read(input, input_buffer + input_overlap, sample_size);
/* Do the converting */
do_fftw(fftw_state, input_buffer, output_buffer, input_buffer_size, output_buffer_size, 0);
/* Write output data */
cat_write(output, output_buffer + overlap, sample_size / downsample_factor);
}
return 0;
}
