I just read the thread, and someone mentioned C, so here goes:

$ cat 879430.cpp 
#include <stdio.h>

int *decode(unsigned char *buf, int buflen) {
    static int retval[201];
    int tmp=0;
    int mask=0;
    int *outbuf=retval;
    unsigned char *end=buf+buflen;
    while (buf < end) {
        int t=*buf & 0xc0;
    
        if (t==0xc0) {
            tmp =*buf++<<16;
            tmp|=*buf++<<8;
            tmp|=*buf++;
            mask=0x3fffff;
        }
        else if (t==0x80) {
            tmp =*buf++<<8;
            tmp|=*buf++;
            mask=0x3fff;
        }
        else {
            tmp =*buf++;
            mask=0x7f;
        }
        *outbuf++ = tmp&mask;
    }
    *outbuf++ = -1; // sentinel value: EOList
    return retval;
}

unsigned char foo[] = {
    0x55,            // 85
    0xaa, 0xaa,        // 10922
    0xcc, 0xcc, 0xcc,    // 838860
    0
};

int main( void ) {
    int *t = decode(foo, sizeof(foo));
    while (*t != -1) {
        printf("0x%06x  %7u\n", *t, *t);
        t++;
    }
    return 1;
}
$ gcc 879430.cpp  -lstdc++

$ ./a.out
0x000055       85
0x002aaa    10922
0x0ccccc   838860
0x000000        0

[download]

...roboticus

When your only tool is a hammer, all problems look like your thumb.

In reply to Re: [NOT] How would you decode this? by roboticus
in thread [NOT] How would you decode this? by BrowserUk

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