downsample.c

#include "presto.h"
#include "downsample_cmd.h"

#ifdef USEDMALLOC
#include "dmalloc.h"
#endif

int main(int argc, char *argv[])
{
    FILE *infile, *outfile;
    int ii, jj, bufflen = 10000, numread;
    long long N = 0;
    float *inbuffer = NULL, *outbuffer = NULL;
    short useshorts = 0, *sinbuffer = NULL, *soutbuffer = NULL;
    char *rootfilenm, *outname;
    infodata idata;
    Cmdline *cmd;

    /* Call usage() if we have no command line arguments */

    if (argc == 1) {
        Program = argv[0];
        printf("\n");
        usage();
        exit(1);
    }

    /* Parse the command line using the excellent program Clig */

    cmd = parseCmdline(argc, argv);

#ifdef DEBUG
    showOptionValues();
#endif

    printf("\n\n");
    printf("     Time Series Downsampling Routine\n");
    printf("               Sept, 2002\n\n");

    {
        int hassuffix = 0;
        char *suffix;

        hassuffix = split_root_suffix(cmd->argv[0], &rootfilenm, &suffix);
        if (hassuffix) {
            if (strcmp(suffix, "sdat") == 0)
                useshorts = 1;
            if (strcmp(suffix, "dat") != 0 && strcmp(suffix, "sdat") != 0) {
                printf
                    ("\nInput file ('%s') must be a time series ('.dat' or '.sdat')!\n\n",
                     cmd->argv[0]);
                free(suffix);
                exit(0);
            }
            free(suffix);
        } else {
            printf
                ("\nInput file ('%s') must be a time series ('.dat' or '.sdat')!\n\n",
                 cmd->argv[0]);
            exit(0);
        }
        if (cmd->outfileP) {
            outname = cmd->outfile;
        } else {
            outname = (char *) calloc(strlen(rootfilenm) + 11, sizeof(char));
            if (useshorts)
                sprintf(outname, "%s_D%d.sdat", rootfilenm, cmd->factor);
            else
                sprintf(outname, "%s_D%d.dat", rootfilenm, cmd->factor);
        }
    }

    /* Read the info file */

    readinf(&idata, rootfilenm);
    if (strlen(remove_whitespace(idata.object)) > 0) {
        printf("Downsampling %s data from '%s'.\n\n",
               remove_whitespace(idata.object), cmd->argv[0]);
    } else {
        printf("Downsampling data from '%s'.\n\n", cmd->argv[0]);
    }

    /* Open files and create arrays */

    infile = chkfopen(argv[1], "rb");
    outfile = chkfopen(outname, "wb");

    /* Read and downsample */

    if (useshorts) {
        sinbuffer = gen_svect(bufflen * cmd->factor);
        soutbuffer = gen_svect(bufflen);
        while ((numread =
                chkfread(sinbuffer, sizeof(short), bufflen * cmd->factor, infile))) {
            for (ii = 0; ii < numread / cmd->factor; ii++) {
                soutbuffer[ii] = 0;
                for (jj = 0; jj < cmd->factor; jj++)
                    soutbuffer[ii] += sinbuffer[cmd->factor * ii + jj];
            }
            chkfwrite(soutbuffer, sizeof(short), numread / cmd->factor, outfile);
            N += numread / cmd->factor;
        }
        vect_free(sinbuffer);
        vect_free(soutbuffer);
    } else {
        inbuffer = gen_fvect(bufflen * cmd->factor);
        outbuffer = gen_fvect(bufflen);
        while ((numread =
                chkfread(inbuffer, sizeof(float), bufflen * cmd->factor, infile))) {
            for (ii = 0; ii < numread / cmd->factor; ii++) {
                outbuffer[ii] = 0;
                for (jj = 0; jj < cmd->factor; jj++)
                    outbuffer[ii] += inbuffer[cmd->factor * ii + jj];
            }
            chkfwrite(outbuffer, sizeof(float), numread / cmd->factor, outfile);
            N += numread / cmd->factor;
        }
        vect_free(inbuffer);
        vect_free(outbuffer);
    }
    printf("Done.  Wrote %lld points.\n\n", N);

    /* Write the new info file */

    idata.dt = idata.dt * cmd->factor;
    idata.numonoff = 0;
    idata.N = (double) N;
    strncpy(idata.name, outname, strlen(outname) - 4);
    if (useshorts)
        idata.name[strlen(outname) - 5] = '\0';
    else
        idata.name[strlen(outname) - 4] = '\0';
    writeinf(&idata);

    fclose(infile);
    fclose(outfile);
    free(rootfilenm);
    if (!cmd->outfileP)
        free(outname);
    exit(0);
}