/*
 * I guess more for a feeling of completeness than anything else,
 * here is the 24bit to 12bit converter written in generic C. It's
 * so basic it should compile and run everywhere; it's been tested
 * on macosx. Compile and run like "24to12 <24bitrawinfile >foo.jbp"
 *
 * "Released to the public domain."
 * */

#include <stdio.h>

int nibcount = 0;

void put4bits(int bits)
{
	static unsigned char outbyte;

	outbyte = (outbyte << 4) | ((bits & 0xF));
	if ((++nibcount & 1) == 0) /* Have a full byte every two nibbles*/
		putchar(outbyte);
}

main()
{
	int inbyte;

	while(1) {
		inbyte = getchar();
		if (inbyte == EOF)
			break;
		put4bits((inbyte)>>4);
	}
}