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min freqs fn fix, finished bits+huffval generation

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Muaz Ahmad 2023-12-04 13:01:11 +05:00
parent a25213fa2d
commit af99b90f9c
1 changed files with 45 additions and 1 deletions
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46
src/output.zig
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@ -49,6 +49,10 @@ const Scan = struct {
const h = buff.Y_quant.len;
const w = buff.Y_quant[0].len;
for (0..4) |i| {
@memset(self.freqs[i], 0);
}
for (0..h) |x| {
for (0..w) |y| {
for (0..4) |Y_sub_i| {
@ -80,6 +84,7 @@ inline fn get_idx_min2(freqs: []u32) ?struct { usize, usize } {
if (!is_init_1) {
min1 = freqs[i];
min1_idx = i;
is_init_1 = true;
} else if (!is_init_2) {
if (freqs[i] < min1) {
min2 = min1;
@ -90,6 +95,7 @@ inline fn get_idx_min2(freqs: []u32) ?struct { usize, usize } {
min2 = freqs[i];
min2_idx = i;
}
is_init_2 = true;
} else if (freqs[i] < min1) {
min1 = freqs[i];
min1_idx = i;
@ -105,14 +111,15 @@ inline fn get_idx_min2(freqs: []u32) ?struct { usize, usize } {
}
inline fn gen_huffman(huff: *Huffman, freqs: []u32) !void {
freqs[freqs.len - 1] = 1;
_ = huff;
var codesizes = [_]u8{0} ** 257;
var others = [_]u9{0x1ff} ** 257;
while (get_idx_min2(freqs)) |tmp| {
var v1 = tmp.@"0";
var v2 = tmp.@"1";
freqs[v1] += freqs[v2];
freqs[v2] = 0;
codesizes[v1] += 1;
while (others[v1] != 0x1ff) : (codesizes[v1] += 1) {
v1 = others[v1];
@ -123,6 +130,43 @@ inline fn gen_huffman(huff: *Huffman, freqs: []u32) !void {
v2 = others[v2];
}
}
var bits = [_]u8{0} ** 33;
for (0..freqs.len) |i| {
if (codesizes[i] != 0) {
bits[codesizes[i]] += 1;
}
}
var i: usize = 32;
while (i > 16) {
if (bits[i] > 0) {
var j = i - 2;
while (bits[j] <= 0) : (j -= 1) {
bits[i] -= 2;
bits[i - 1] += 1;
bits[j + 1] += 2;
bits[j] -= 1;
}
} else {
i -= 1;
}
}
while (bits[i] == 0) : (i -= 1) {}
bits[i] -= 1;
var k: usize = 0;
var huffval = [_]u8{0} ** 256;
for (1..33) |i_| {
for (0..freqs.len - 1) |j| {
if (codesizes[j] == i_) {
huffval[k] = @truncate(j);
k += 1;
}
}
}
std.debug.print("{any}\n{any}\n\n", .{ bits, huffval });
}
inline fn get_size(n: i16) u8 {