teeworlds
Version:
Library for (ingame) teeworlds bots.
226 lines (199 loc) • 7.22 kB
text/typescript
let FREQ_TABLE = [
1 << 30, 4545, 2657, 431, 1950, 919, 444, 482, 2244, 617, 838, 542, 715, 1814, 304, 240, 754, 212, 647, 186,
283, 131, 146, 166, 543, 164, 167, 136, 179, 859, 363, 113, 157, 154, 204, 108, 137, 180, 202, 176,
872, 404, 168, 134, 151, 111, 113, 109, 120, 126, 129, 100, 41, 20, 16, 22, 18, 18, 17, 19,
16, 37, 13, 21, 362, 166, 99, 78, 95, 88, 81, 70, 83, 284, 91, 187, 77, 68, 52, 68,
59, 66, 61, 638, 71, 157, 50, 46, 69, 43, 11, 24, 13, 19, 10, 12, 12, 20, 14, 9,
20, 20, 10, 10, 15, 15, 12, 12, 7, 19, 15, 14, 13, 18, 35, 19, 17, 14, 8, 5,
15, 17, 9, 15, 14, 18, 8, 10, 2173, 134, 157, 68, 188, 60, 170, 60, 194, 62, 175, 71,
148, 67, 167, 78, 211, 67, 156, 69, 1674, 90, 174, 53, 147, 89, 181, 51, 174, 63, 163, 80,
167, 94, 128, 122, 223, 153, 218, 77, 200, 110, 190, 73, 174, 69, 145, 66, 277, 143, 141, 60,
136, 53, 180, 57, 142, 57, 158, 61, 166, 112, 152, 92, 26, 22, 21, 28, 20, 26, 30, 21,
32, 27, 20, 17, 23, 21, 30, 22, 22, 21, 27, 25, 17, 27, 23, 18, 39, 26, 15, 21,
12, 18, 18, 27, 20, 18, 15, 19, 11, 17, 33, 12, 18, 15, 19, 18, 16, 26, 17, 18,
9, 10, 25, 22, 22, 17, 20, 16, 6, 16, 15, 20, 14, 18, 24, 335, 1517],
HUFFMAN_EOF_SYMBOL = 256,
HUFFMAN_MAX_SYMBOLS = HUFFMAN_EOF_SYMBOL + 1,
HUFFMAN_MAX_NODES = HUFFMAN_MAX_SYMBOLS * 2 - 1,
HUFFMAN_LUTBITS = 10,
HUFFMAN_LUTSIZE = 1 << HUFFMAN_LUTBITS,
HUFFMAN_LUTMASK = HUFFMAN_LUTSIZE - 1;
interface HuffmanNode {
bits: number;
numbits: number;
left: number;
right: number;
symbol: number;
}
interface HuffmanConstructNode {
node_id: number;
frequency: number;
}
export class Huffman {
nodes: HuffmanNode[];
decode_lut: number[];
num_nodes: number;
start_node_index: number;
constructor(frequencies = FREQ_TABLE) {
this.nodes = new Array<HuffmanNode>(HUFFMAN_MAX_NODES);
for (let i = 0; i < HUFFMAN_MAX_NODES; i++) {
this.nodes[i] = {} as HuffmanNode;
}
this.decode_lut = new Array<number>(HUFFMAN_LUTSIZE);
this.num_nodes = 0;
this.start_node_index = 0;
this.construct_tree(frequencies);
for (let i = 0; i < HUFFMAN_LUTSIZE; i++) {
let bits = i;
let broke = false;
let index = this.start_node_index;
for (let x = 0; x < HUFFMAN_LUTBITS; x++) {
if (bits & 1)
index = this.nodes[index].right;
else
index = this.nodes[index].left;
bits >>= 1;
if (this.nodes[index].numbits) {
this.decode_lut[i] = index;
broke = true;
break;
}
}
if (!broke) {
this.decode_lut[i] = index;
}
}
}
set_bits_r(node_index: number, bits: number, depth: number) {
if (this.nodes[node_index].right != 0xffff)
this.set_bits_r(this.nodes[node_index].right, bits | (1 << depth), depth + 1)
if (this.nodes[node_index].left != 0xffff)
this.set_bits_r(this.nodes[node_index].left, bits, depth + 1)
if (this.nodes[node_index].numbits) {
this.nodes[node_index].bits = bits;
this.nodes[node_index].numbits = depth;
}
}
bubble_sort(index_list: number[], node_list: HuffmanConstructNode[], size: number) {
let changed = true;
while (changed) {
changed = false;
for (let i = 0; i < size-1; i++) {
if (node_list[index_list[i]].frequency < node_list[index_list[i + 1]].frequency) {
let temp = index_list[i];
index_list[i] = index_list[i + 1];
index_list[i + 1] = temp;
changed = true;
}
}
size--;
}
return index_list;
}
construct_tree(frequencies = FREQ_TABLE) {
let nodes_left_storage: HuffmanConstructNode[] = new Array<HuffmanConstructNode>(HUFFMAN_MAX_SYMBOLS);
for (let i = 0; i < HUFFMAN_MAX_SYMBOLS; i++) {
nodes_left_storage[i] = {} as HuffmanConstructNode;
}
let nodes_left: number[] = new Array<number>(HUFFMAN_MAX_SYMBOLS);
let num_nodes_left = HUFFMAN_MAX_SYMBOLS;
for (let i = 0; i < HUFFMAN_MAX_SYMBOLS; i++) {
this.nodes[i].numbits = 0xFFFFFFFF;
this.nodes[i].symbol = i;
this.nodes[i].left = 0xFFFF;
this.nodes[i].right = 0xFFFF;
if (i == HUFFMAN_EOF_SYMBOL) {
nodes_left_storage[i].frequency = 1;
} else
nodes_left_storage[i].frequency = frequencies[i];
nodes_left_storage[i].node_id = i;
nodes_left[i] = i;
}
this.num_nodes = HUFFMAN_MAX_SYMBOLS;
while (num_nodes_left > 1) {
nodes_left = this.bubble_sort(nodes_left, nodes_left_storage, num_nodes_left);
this.nodes[this.num_nodes].numbits = 0;
this.nodes[this.num_nodes].left = nodes_left_storage[nodes_left[num_nodes_left - 1]].node_id
this.nodes[this.num_nodes].right = nodes_left_storage[nodes_left[num_nodes_left - 2]].node_id
nodes_left_storage[nodes_left[num_nodes_left - 2]].node_id = this.num_nodes;
nodes_left_storage[nodes_left[num_nodes_left - 2]].frequency = nodes_left_storage[nodes_left[num_nodes_left - 1]].frequency
+ nodes_left_storage[nodes_left[num_nodes_left - 2]].frequency
this.num_nodes++;
num_nodes_left--;
}
this.start_node_index = this.num_nodes-1;
this.set_bits_r(this.start_node_index, 0, 0);
}
compress(inp_buffer: Buffer, start_index = 0, size: number = 0): Buffer {
let output = [];
let bits = 0;
let bitcount = 0;
if (size == 0)
size = inp_buffer.byteLength;
inp_buffer = inp_buffer.slice(start_index, start_index + size);
for (let i = 0; i < size; i++) {
let x = inp_buffer[i];
bits |= this.nodes[x].bits << bitcount;
bitcount += this.nodes[x].numbits;
while (bitcount >= 8) {
output.push(bits & 0xff);
bits >>= 8;
bitcount -= 8;
}
}
bits |= this.nodes[HUFFMAN_EOF_SYMBOL].bits << bitcount;
bitcount += this.nodes[HUFFMAN_EOF_SYMBOL].numbits;
while (bitcount >= 8) {
output.push(bits & 0xff);
bits >>= 8;
bitcount -= 8;
}
output.push(bits);
return Buffer.from(output);
}
decompress(inp_buffer: Buffer, size = 0): Buffer {
let bits = 0;
let bitcount = 0;
let eof = this.nodes[HUFFMAN_EOF_SYMBOL];
let output = [];
if (size == 0)
size = inp_buffer.byteLength;
inp_buffer = inp_buffer.slice(0, size);
let src_index = 0;
while (true) {
let node_i = -1;
if (bitcount >= HUFFMAN_LUTBITS)
node_i = this.decode_lut[bits & HUFFMAN_LUTMASK];
while (bitcount < 24 && src_index != size) {
bits |= inp_buffer[src_index] << bitcount;
bitcount += 8;
src_index++;
}
if (node_i == -1)
node_i = this.decode_lut[bits & HUFFMAN_LUTMASK];
if (this.nodes[node_i].numbits) {
bits >>= this.nodes[node_i].numbits;
bitcount -= this.nodes[node_i].numbits;
} else {
bits >>= HUFFMAN_LUTBITS;
bitcount -= HUFFMAN_LUTBITS;
while (true) {
if (bits & 1) {
node_i = this.nodes[node_i].right;
} else
node_i = this.nodes[node_i].left;
bitcount -= 1;
bits >>= 1;
if (this.nodes[node_i].numbits)
break;
if (bitcount == 0)
throw new Error("No more bits, decoding error")
}
}
if (this.nodes[node_i] == eof)
break;
output.push(this.nodes[node_i].symbol);
}
return Buffer.from(output);
}
}