Translates octal digits into ASCII art, with the brightness correlated to the magnitude of the digit. The input may be either ASCII octal digits or machine octal. Try it on random data, or the compiled executable of the program (and vary your terminal width). A hexidecimal version is also available.

octBright.c

/* octBright.c - visualize octal data with brightness
 * Max Goldstein
 *
 * example usage:
 * $ od -o < /dev/random | sed 's/^[0-9]* +//' | tr -d ' ' | ./octBright
 */

#include <stdio.h>

int main(){
    while(1){
        int c = getchar();
        if (c == EOF){
            break;
        }
        if (c >= '0' && c <= '7'){
            c -= '0';
        }
        if (c >= 0 && c <= 7){
            putchar(".-~:;#$@"[c]);
        }
    }
    return 0;
}