Hi! I'm working on several compression techniques, and one for 8-bit systems uses MTF. It seems to be pretty good there but not elsewhere. Now, I'm wondering how I can improve it. Wikipedia's article on MTF recommended I use it as a back end to BWT. However, applying it only cost me. 🙁 This technique does pretty well but not very well. I'm looking for ways to better MTF. Following is the code I'm using to write a MTF byte:

1void mtfWriteVal (void)
2{
3	unsigned char m=mtfGetVal (CPos[k]);
4	//writeoutf (CPos[k], 8); return;
5	/*if (0 && m<32) {
6		writeoutf_x2 (0);
7		writeoutf (m, 5);
8	//} else if (m<128+16+32+32) {
9	} else //if (m<32+32+64) {
10//++brdrcol;
11	*/
12	//WriteDist (m-32, 128-32);
13brdrcol=m;
14	if (m<32) {
15		writeoutf_11 ();
16		writeoutf (m, 5);
17	//} else if (m<128+16+32+32) {
18	} else if (m<64) {
19		//writeoutf_11 ();
20		writeoutf_x2 (2);
21		writeoutf (m-32, 5);
22	} else if (m<128) {
23		//writeoutf_01 ();
24		writeoutf_x3 (5);
25		writeoutf (m-64, 6);
26	} else {
27		writeoutf_x3 (6);
28		// if (m<192) {writeoutf_11 (); writeoutf (m-128, 6);}
29		// else {writeoutf_01 (); writeoutf (m-192, 6);}
30		writeoutf (m-128, 7);
31	} //continue;
32}

where mtfGetVal() converts the current byte to an index in the MTF table, the writeoutf_##() functions write the second number of bits to the output and writeoutf() writes the number of bits given in the second parameter. BTW, brdrcol is just a way to visualize the writing of the converted variable.