#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
+#include <string.h>
#include <assert.h>
#include <math.h>
#include "ryg_rans/rans_byte.h"
#include "ryg_rans/renormalize.h"
+#include <algorithm>
#include <memory>
+#include <numeric>
+#include <random>
+#include <vector>
+#include <unordered_map>
#define WIDTH 1280
#define HEIGHT 720
+#define WIDTH_BLOCKS (WIDTH/8)
+#define WIDTH_BLOCKS_CHROMA (WIDTH/16)
+#define HEIGHT_BLOCKS (HEIGHT/8)
+#define NUM_BLOCKS (WIDTH_BLOCKS * HEIGHT_BLOCKS)
+#define NUM_BLOCKS_CHROMA (WIDTH_BLOCKS_CHROMA * HEIGHT_BLOCKS)
+
#define NUM_SYMS 256
#define ESCAPE_LIMIT (NUM_SYMS - 1)
+#define BLOCKS_PER_STREAM 320
+
+// If you set this to 1, the program will try to optimize the placement
+// of coefficients to rANS probability distributions. This is randomized,
+// so you might want to run it a few times.
+#define FIND_OPTIMAL_STREAM_ASSIGNMENT 0
+#define NUM_CLUSTERS 4
static constexpr uint32_t prob_bits = 12;
static constexpr uint32_t prob_scale = 1 << prob_bits;
uint32_t cum_freqs[NUM_SYMS + 1];
void clear();
- void count_freqs(uint8_t const* in, size_t nbytes);
void calc_cum_freqs();
void normalize_freqs(uint32_t target_total);
};
freqs[i] = 0;
}
-void SymbolStats::count_freqs(uint8_t const* in, size_t nbytes)
-{
- clear();
-
- for (size_t i=0; i < nbytes; i++)
- freqs[in[i]]++;
-}
-
void SymbolStats::calc_cum_freqs()
{
cum_freqs[0] = 0;
cum_freqs[i+1] = cum_freqs[i] + freqs[i];
}
-static double cache[NUM_SYMS + 1][prob_scale + 1];
-static double log2cache[prob_scale + 1];
-static int64_t cachefill = 0;
-
-double find_optimal_cost(const uint32_t *cum_freqs, int sym_to, int available_slots)
-{
- assert(sym_to >= 0);
-
- while (sym_to > 0 && cum_freqs[sym_to] == cum_freqs[sym_to - 1]) { --sym_to; }
- if (cache[sym_to][available_slots] >= 0.0) {
- //printf("CACHE: %d,%d\n", sym_to, available_slots);
- return cache[sym_to][available_slots];
- }
- if (sym_to == 0) {
- return 0.0;
- }
- if (sym_to == 1) {
- return cum_freqs[0] * log2cache[available_slots];
- }
- if (available_slots == 1) {
- return cum_freqs[0] * log2cache[1] + find_optimal_cost(cum_freqs, sym_to - 1, 0);
- }
-
-// printf("UNCACHE: %d,%d\n", sym_to, available_slots);
-#if 0
- // ok, test all possible options for the last symbol (TODO: save the choice)
- double best_so_far = HUGE_VAL;
- //for (int i = num_syms - 1; i < available_slots; ++i) {
- double f = freqs[sym_to - 1];
- for (int i = available_slots; i --> 0; ) {
- double cost1 = f * log2cache[available_slots - i];
- double cost2 = find_optimal_cost(freqs, sym_to - 1, i);
-
- if (sym_to == 3 && available_slots == 838) {
- printf("%d %f\n", i, cost1 + cost2);
- } else
- if (cost1 + cost2 > best_so_far) {
- break;
- }
- best_so_far = cost1 + cost2;
- }
-#elif 1
- // Minimize the number of total bits spent as a function of how many slots
- // we assign to this symbol.
- //
- // The cost function is convex (I don't know how to prove it, but it makes
- // intuitively a lot of sense). Find a reasonable guess and see what way
- // we should search, then iterate until we either hit the end or we start
- // increasing again.
- double f = cum_freqs[sym_to - 1] - cum_freqs[sym_to - 2];
- double start = lrint(available_slots * f / cum_freqs[sym_to - 1]);
-
- int x1 = std::max<int>(floor(start), 1);
- int x2 = x1 + 1;
-
- double f1 = f * log2cache[x1] + find_optimal_cost(cum_freqs, sym_to - 1, available_slots - x1);
- double f2 = f * log2cache[x2] + find_optimal_cost(cum_freqs, sym_to - 1, available_slots - x2);
-
- int x, direction; // -1 or +1
- double best_so_far = std::min(f1, f2);
- if (isinf(f1) && isinf(f2)) {
- // The cost isn't infinite due to the first term, so we need to go downwards
- // to give the second term more room to breathe.
- x = x1;
- direction = -1;
- } else if (f1 < f2) {
- x = x1;
- direction = -1;
- } else {
- x = x2;
- direction = 1;
- }
-
- //printf("[%d,%d] freq=%ld cumfreq=%d From %d and %d, chose %d [%f] and direction=%d\n",
- // sym_to, available_slots, freqs[sym_to - 1], cum_freqs[sym_to - 1], x1, x2, x, best_so_far, direction);
-
- while ((x + direction) > 0 && (x + direction) <= available_slots) {
- x += direction;
- double fn = f * log2cache[x] + find_optimal_cost(cum_freqs, sym_to - 1, available_slots - x);
- // printf("[%d,%d] %d is %f\n", sym_to, available_slots, x, fn);
- if (fn > best_so_far) {
- break;
- }
- best_so_far = fn;
- }
-#endif
- if (++cachefill % 131072 == 0) {
- // printf("%d,%d = %f (cachefill = %.2f%%)\n", sym_to, available_slots, best_so_far,
- // 100.0 * (cachefill / double((NUM_SYMS + 1) * (prob_scale + 1))));
- }
- assert(best_so_far >= 0.0);
- assert(cache[sym_to][available_slots] < 0.0);
- cache[sym_to][available_slots] = best_so_far;
- return best_so_far;
-}
-
-double find_optimal_cost(const uint32_t *cum_freqs, const uint64_t *freqs)
-{
- for (int j = 0; j <= NUM_SYMS; ++j) {
- for (unsigned k = 0; k <= prob_scale; ++k) {
- cache[j][k] = -1.0;
- }
- }
- for (unsigned k = 0; k <= prob_scale; ++k) {
- log2cache[k] = -log2(k * (1.0 / prob_scale));
- //printf("log2cache[%d] = %f\n", k, log2cache[k]);
- }
- cachefill = 0;
- double ret = find_optimal_cost(cum_freqs, NUM_SYMS, prob_scale);
- printf("Used %ld function invocations\n", cachefill);
- return ret;
-}
-
void SymbolStats::normalize_freqs(uint32_t target_total)
{
uint64_t real_freq[NUM_SYMS + 1]; // hack
OptimalRenormalize(cum_freqs, NUM_SYMS, prob_scale);
-#if 0
- double optimal_cost = find_optimal_cost(cum_freqs + 1, real_freq + 1);
-
- // resample distribution based on cumulative freqs
- for (int i = 1; i <= NUM_SYMS; i++)
- //cum_freqs[i] = ((uint64_t)target_total * cum_freqs[i])/cur_total;
- cum_freqs[i] = lrint(cum_freqs[i] * double(target_total) / cur_total);
-
- // if we nuked any non-0 frequency symbol to 0, we need to steal
- // the range to make the frequency nonzero from elsewhere.
- //
- // this is not at all optimal, i'm just doing the first thing that comes to mind.
- for (int i=0; i < NUM_SYMS; i++) {
- if (freqs[i] && cum_freqs[i+1] == cum_freqs[i]) {
- // symbol i was set to zero freq
-
- // find best symbol to steal frequency from (try to steal from low-freq ones)
- uint32_t best_freq = ~0u;
- int best_steal = -1;
- for (int j=0; j < NUM_SYMS; j++) {
- uint32_t freq = cum_freqs[j+1] - cum_freqs[j];
- if (freq > 1 && freq < best_freq) {
- best_freq = freq;
- best_steal = j;
- }
- }
- assert(best_steal != -1);
-
- // and steal from it!
- if (best_steal < i) {
- for (int j = best_steal + 1; j <= i; j++)
- cum_freqs[j]--;
- } else {
- assert(best_steal > i);
- for (int j = i + 1; j <= best_steal; j++)
- cum_freqs[j]++;
- }
- }
- }
-#endif
-
// calculate updated freqs and make sure we didn't screw anything up
assert(cum_freqs[0] == 0 && cum_freqs[NUM_SYMS] == target_total);
for (int i=0; i < NUM_SYMS; i++) {
calc_cost, (calc_cost - ideal_cost) / 8.0, total_loss / 8.0, total_loss_with_dp / 8.0);
}
-SymbolStats stats[64];
+SymbolStats stats[128];
-int pick_stats_for(int y, int x)
+#if FIND_OPTIMAL_STREAM_ASSIGNMENT
+// Distance from one stream to the other, based on a hacked-up K-L divergence.
+float kl_dist[64][64];
+#endif
+
+const int luma_mapping[64] = {
+ 0, 0, 1, 1, 2, 2, 3, 3,
+ 0, 0, 1, 2, 2, 2, 3, 3,
+ 1, 1, 2, 2, 2, 3, 3, 3,
+ 1, 1, 2, 2, 2, 3, 3, 3,
+ 1, 2, 2, 2, 2, 3, 3, 3,
+ 2, 2, 2, 2, 3, 3, 3, 3,
+ 2, 2, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3,
+};
+const int chroma_mapping[64] = {
+ 0, 1, 1, 2, 2, 2, 3, 3,
+ 1, 1, 2, 2, 2, 3, 3, 3,
+ 2, 2, 2, 2, 3, 3, 3, 3,
+ 2, 2, 2, 3, 3, 3, 3, 3,
+ 2, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3,
+ 3, 3, 3, 3, 3, 3, 3, 3,
+};
+
+int pick_stats_for(int x, int y, bool is_chroma)
{
- //return std::min<int>(hypot(x, y), 7);
- return std::min<int>(x + y, 7);
- //if (x + y >= 7) return 7;
- //return x + y;
- //return y * 8 + x;
-#if 0
- if (y == 0 && x == 0) {
- return 0;
+#if FIND_OPTIMAL_STREAM_ASSIGNMENT
+ return y * 8 + x + is_chroma * 64;
+#else
+ if (is_chroma) {
+ return chroma_mapping[y * 8 + x] + 4;
} else {
- return 1;
+ return luma_mapping[y * 8 + x];
}
#endif
}
RansEncoder()
{
out_buf.reset(new uint8_t[out_max_size]);
- sign_buf.reset(new uint8_t[max_num_sign]);
clear();
}
- void init_prob(const SymbolStats &s)
+ void init_prob(SymbolStats &s)
{
for (int i = 0; i < NUM_SYMS; i++) {
- printf("%d: cumfreqs=%d freqs=%d prob_bits=%d\n", i, s.cum_freqs[i], s.freqs[i], prob_bits);
- RansEncSymbolInit(&esyms[i], s.cum_freqs[i], s.freqs[i], prob_bits);
+ //printf("%d: cumfreqs=%d freqs=%d prob_bits=%d\n", i, s.cum_freqs[i], s.freqs[i], prob_bits + 1);
+ RansEncSymbolInit(&esyms[i], s.cum_freqs[i], s.freqs[i], prob_bits + 1);
}
+ sign_bias = s.cum_freqs[NUM_SYMS];
}
void clear()
{
out_end = out_buf.get() + out_max_size;
- sign_end = sign_buf.get() + max_num_sign;
ptr = out_end; // *end* of output buffer
- sign_ptr = sign_end; // *end* of output buffer
RansEncInit(&rans);
- free_sign_bits = 0;
}
uint32_t save_block(FILE *codedfp) // Returns number of bytes.
//printf("post-flush = %08x\n", rans);
uint32_t num_rans_bytes = out_end - ptr;
+ if (num_rans_bytes == last_block.size() &&
+ memcmp(last_block.data(), ptr, last_block.size()) == 0) {
+ write_varint(0, codedfp);
+ clear();
+ return 1;
+ } else {
+ last_block = string((const char *)ptr, num_rans_bytes);
+ }
+
write_varint(num_rans_bytes, codedfp);
//fwrite(&num_rans_bytes, 1, 4, codedfp);
fwrite(ptr, 1, num_rans_bytes, codedfp);
//printf("first rANS bytes: %02x %02x %02x %02x %02x %02x %02x %02x\n", ptr[0], ptr[1], ptr[2], ptr[3], ptr[4], ptr[5], ptr[6], ptr[7]);
- if (free_sign_bits > 0) {
- *sign_ptr <<= free_sign_bits;
- }
-
-#if 1
- uint32_t num_sign_bytes = sign_end - sign_ptr;
- write_varint((num_sign_bytes << 3) | free_sign_bits, codedfp);
- fwrite(sign_ptr, 1, num_sign_bytes, codedfp);
-#endif
clear();
- printf("Saving block: %d rANS bytes, %d sign bytes\n", num_rans_bytes, num_sign_bytes);
- return num_rans_bytes + num_sign_bytes;
+ //printf("Saving block: %d rANS bytes\n", num_rans_bytes);
+ return num_rans_bytes;
//return num_rans_bytes;
}
void encode_coeff(short signed_k)
{
- printf("encoding coeff %d\n", signed_k);
- short k = abs(signed_k);
+ //printf("encoding coeff %d (sym %d), rans before encoding = %08x\n", signed_k, ((abs(signed_k) - 1) & 255), rans);
+ unsigned short k = abs(signed_k);
if (k >= ESCAPE_LIMIT) {
// Put the coefficient as a 1/(2^12) symbol _before_
// the 255 coefficient, since the decoder will read the
RansEncPut(&rans, &ptr, k, 1, prob_bits);
k = ESCAPE_LIMIT;
}
- if (k != 0) {
-#if 1
- if (free_sign_bits == 0) {
- --sign_ptr;
- *sign_ptr = 0;
- free_sign_bits = 8;
- }
- *sign_ptr <<= 1;
- *sign_ptr |= (signed_k < 0);
- --free_sign_bits;
-#else
- RansEncPut(&rans, &ptr, (k < 0) ? prob_scale / 2 : 0, prob_scale / 2, prob_bits);
-#endif
+ RansEncPutSymbol(&rans, &ptr, &esyms[(k - 1) & (NUM_SYMS - 1)]);
+ if (signed_k < 0) {
+ rans += sign_bias;
}
- RansEncPutSymbol(&rans, &ptr, &esyms[k]);
}
private:
static constexpr size_t out_max_size = 32 << 20; // 32 MB.
static constexpr size_t max_num_sign = 1048576; // Way too big. And actually bytes.
- unique_ptr<uint8_t[]> out_buf, sign_buf;
- uint8_t *out_end, *sign_end;
- uint8_t *ptr, *sign_ptr;
+ unique_ptr<uint8_t[]> out_buf;
+ uint8_t *out_end;
+ uint8_t *ptr;
RansState rans;
- size_t free_sign_bits;
RansEncSymbol esyms[NUM_SYMS];
+ uint32_t sign_bias;
+
+ std::string last_block;
};
static constexpr int dc_scalefac = 8; // Matches the FDCT's gain.
}
}
+#if FIND_OPTIMAL_STREAM_ASSIGNMENT
+double find_best_assignment(const int *medoids, int *assignment)
+{
+ double current_score = 0.0;
+ for (int i = 0; i < 64; ++i) {
+ int best_medoid = medoids[0];
+ float best_medoid_score = kl_dist[i][medoids[0]];
+ for (int j = 1; j < NUM_CLUSTERS; ++j) {
+ if (kl_dist[i][medoids[j]] < best_medoid_score) {
+ best_medoid = medoids[j];
+ best_medoid_score = kl_dist[i][medoids[j]];
+ }
+ }
+ assignment[i] = best_medoid;
+ current_score += best_medoid_score;
+ }
+ return current_score;
+}
+
+void find_optimal_stream_assignment(int base)
+{
+ double inv_sum[64];
+ for (unsigned i = 0; i < 64; ++i) {
+ double s = 0.0;
+ for (unsigned k = 0; k < NUM_SYMS; ++k) {
+ s += stats[i + base].freqs[k] + 0.5;
+ }
+ inv_sum[i] = 1.0 / s;
+ }
+
+ for (unsigned i = 0; i < 64; ++i) {
+ for (unsigned j = 0; j < 64; ++j) {
+ double d = 0.0;
+ for (unsigned k = 0; k < NUM_SYMS; ++k) {
+ double p1 = (stats[i + base].freqs[k] + 0.5) * inv_sum[i];
+ double p2 = (stats[j + base].freqs[k] + 0.5) * inv_sum[j];
+
+ // K-L divergence is asymmetric; this is a hack.
+ d += p1 * log(p1 / p2);
+ d += p2 * log(p2 / p1);
+ }
+ kl_dist[i][j] = d;
+ //printf("%.3f ", d);
+ }
+ //printf("\n");
+ }
+
+ // k-medoids init
+ int medoids[64]; // only the first NUM_CLUSTERS matter
+ bool is_medoid[64] = { false };
+ std::iota(medoids, medoids + 64, 0);
+ std::random_device rd;
+ std::mt19937 g(rd());
+ std::shuffle(medoids, medoids + 64, g);
+ for (int i = 0; i < NUM_CLUSTERS; ++i) {
+ printf("%d ", medoids[i]);
+ is_medoid[medoids[i]] = true;
+ }
+ printf("\n");
+
+ // assign each data point to the closest medoid
+ int assignment[64];
+ double current_score = find_best_assignment(medoids, assignment);
+
+ for (int i = 0; i < 1000; ++i) {
+ printf("iter %d\n", i);
+ bool any_changed = false;
+ for (int m = 0; m < NUM_CLUSTERS; ++m) {
+ for (int o = 0; o < 64; ++o) {
+ if (is_medoid[o]) continue;
+ int old_medoid = medoids[m];
+ medoids[m] = o;
+
+ int new_assignment[64];
+ double candidate_score = find_best_assignment(medoids, new_assignment);
+
+ if (candidate_score < current_score) {
+ current_score = candidate_score;
+ memcpy(assignment, new_assignment, sizeof(assignment));
+
+ is_medoid[old_medoid] = false;
+ is_medoid[medoids[m]] = true;
+ printf("%f: ", current_score);
+ for (int i = 0; i < 64; ++i) {
+ printf("%d ", assignment[i]);
+ }
+ printf("\n");
+ any_changed = true;
+ } else {
+ medoids[m] = old_medoid;
+ }
+ }
+ }
+ if (!any_changed) break;
+ }
+ printf("\n");
+ std::unordered_map<int, int> rmap;
+ for (int i = 0; i < 64; ++i) {
+ if (i % 8 == 0) printf("\n");
+ if (!rmap.count(assignment[i])) {
+ rmap.emplace(assignment[i], rmap.size());
+ }
+ printf("%d, ", rmap[assignment[i]]);
+ }
+ printf("\n");
+}
+#endif
+
int main(int argc, char **argv)
{
if (argc >= 2)
//double last_cb_cfl_fac = 0.0;
//double last_cr_cfl_fac = 0.0;
+ int max_val_x[8] = {0}, min_val_x[8] = {0};
+ int max_val_y[8] = {0}, min_val_y[8] = {0};
+
// DCT and quantize luma
for (unsigned yb = 0; yb < HEIGHT; yb += 8) {
for (unsigned xb = 0; xb < WIDTH; xb += 8) {
int k = quantize(in_y[coeff_idx], coeff_idx);
coeff_y[(yb + y) * WIDTH + (xb + x)] = k;
+ max_val_x[x] = std::max(max_val_x[x], k);
+ min_val_x[x] = std::min(min_val_x[x], k);
+ max_val_y[y] = std::max(max_val_y[y], k);
+ min_val_y[y] = std::min(min_val_y[y], k);
+
// Store back for reconstruction / PSNR calculation
in_y[coeff_idx] = unquantize(k, coeff_idx);
}
chroma_energy / (WIDTH * HEIGHT), chroma_energy_pred / (WIDTH * HEIGHT));
#endif
- // DC coefficient pred from the right to left
- for (unsigned yb = 0; yb < HEIGHT; yb += 8) {
- for (unsigned xb = 0; xb < WIDTH - 8; xb += 8) {
- coeff_y[yb * WIDTH + xb] -= coeff_y[yb * WIDTH + (xb + 8)];
+ // DC coefficient pred from the right to left (within each slice)
+ for (unsigned block_idx = 0; block_idx < NUM_BLOCKS; block_idx += BLOCKS_PER_STREAM) {
+ int prev_k = 128;
+
+ for (unsigned subblock_idx = BLOCKS_PER_STREAM; subblock_idx --> 0; ) {
+ unsigned yb = (block_idx + subblock_idx) / WIDTH_BLOCKS;
+ unsigned xb = (block_idx + subblock_idx) % WIDTH_BLOCKS;
+ int k = coeff_y[(yb * 8) * WIDTH + (xb * 8)];
+
+ coeff_y[(yb * 8) * WIDTH + (xb * 8)] = k - prev_k;
+
+ prev_k = k;
+ }
+ }
+ for (unsigned block_idx = 0; block_idx < NUM_BLOCKS_CHROMA; block_idx += BLOCKS_PER_STREAM) {
+ int prev_k_cb = 0;
+ int prev_k_cr = 0;
+
+ for (unsigned subblock_idx = BLOCKS_PER_STREAM; subblock_idx --> 0; ) {
+ unsigned yb = (block_idx + subblock_idx) / WIDTH_BLOCKS_CHROMA;
+ unsigned xb = (block_idx + subblock_idx) % WIDTH_BLOCKS_CHROMA;
+ int k_cb = coeff_cb[(yb * 8) * WIDTH/2 + (xb * 8)];
+ int k_cr = coeff_cr[(yb * 8) * WIDTH/2 + (xb * 8)];
+
+ coeff_cb[(yb * 8) * WIDTH/2 + (xb * 8)] = k_cb - prev_k_cb;
+ coeff_cr[(yb * 8) * WIDTH/2 + (xb * 8)] = k_cr - prev_k_cr;
+
+ prev_k_cb = k_cb;
+ prev_k_cr = k_cr;
}
}
fclose(fp);
// For each coefficient, make some tables.
- size_t extra_bits = 0, sign_bits = 0;
+ size_t extra_bits = 0;
for (unsigned i = 0; i < 64; ++i) {
stats[i].clear();
}
for (unsigned y = 0; y < 8; ++y) {
for (unsigned x = 0; x < 8; ++x) {
- SymbolStats &s_luma = stats[pick_stats_for(x, y)];
- SymbolStats &s_chroma = stats[pick_stats_for(x, y) + 8]; // HACK
- //SymbolStats &s_chroma = stats[pick_stats_for(x, y)];
+ SymbolStats &s_luma = stats[pick_stats_for(x, y, false)];
+ SymbolStats &s_chroma = stats[pick_stats_for(x, y, true)];
// Luma
for (unsigned yb = 0; yb < HEIGHT; yb += 8) {
for (unsigned xb = 0; xb < WIDTH; xb += 8) {
- short k = abs(coeff_y[(yb + y) * WIDTH + (xb + x)]);
+ unsigned short k = abs(coeff_y[(yb + y) * WIDTH + (xb + x)]);
if (k >= ESCAPE_LIMIT) {
k = ESCAPE_LIMIT;
extra_bits += 12; // escape this one
}
- if (k != 0) ++sign_bits;
- ++s_luma.freqs[k];
+ ++s_luma.freqs[(k - 1) & (NUM_SYMS - 1)];
}
}
// Chroma
for (unsigned yb = 0; yb < HEIGHT; yb += 8) {
for (unsigned xb = 0; xb < WIDTH/2; xb += 8) {
- short k_cb = abs(coeff_cb[(yb + y) * WIDTH/2 + (xb + x)]);
- short k_cr = abs(coeff_cr[(yb + y) * WIDTH/2 + (xb + x)]);
+ unsigned short k_cb = abs(coeff_cb[(yb + y) * WIDTH/2 + (xb + x)]);
+ unsigned short k_cr = abs(coeff_cr[(yb + y) * WIDTH/2 + (xb + x)]);
if (k_cb >= ESCAPE_LIMIT) {
k_cb = ESCAPE_LIMIT;
extra_bits += 12; // escape this one
k_cr = ESCAPE_LIMIT;
extra_bits += 12; // escape this one
}
- if (k_cb != 0) ++sign_bits;
- if (k_cr != 0) ++sign_bits;
- ++s_chroma.freqs[k_cb];
- ++s_chroma.freqs[k_cr];
+ ++s_chroma.freqs[(k_cb - 1) & (NUM_SYMS - 1)];
+ ++s_chroma.freqs[(k_cr - 1) & (NUM_SYMS - 1)];
}
}
}
}
+
+#if FIND_OPTIMAL_STREAM_ASSIGNMENT
+ printf("Luma:\n");
+ find_optimal_stream_assignment(0);
+ printf("Chroma:\n");
+ find_optimal_stream_assignment(64);
+ exit(0);
+#endif
+
for (unsigned i = 0; i < 64; ++i) {
+ stats[i].freqs[NUM_SYMS - 1] /= 2; // zero, has no sign bits (yes, this is trickery)
stats[i].normalize_freqs(prob_scale);
+ stats[i].cum_freqs[NUM_SYMS] += stats[i].freqs[NUM_SYMS - 1];
+ stats[i].freqs[NUM_SYMS - 1] *= 2;
}
FILE *codedfp = fopen("coded.dat", "wb");
// Luma
for (unsigned y = 0; y < 8; ++y) {
for (unsigned x = 0; x < 8; ++x) {
- SymbolStats &s_luma = stats[pick_stats_for(x, y)];
+ SymbolStats &s_luma = stats[pick_stats_for(x, y, false)];
rans_encoder.init_prob(s_luma);
// Luma
+ std::vector<int> lens;
// need to reverse later
rans_encoder.clear();
size_t num_bytes = 0;
- for (unsigned yb = 0; yb < HEIGHT; yb += 8) {
- for (unsigned xb = 0; xb < WIDTH; xb += 8) {
- int k = coeff_y[(yb + y) * WIDTH + (xb + x)];
- //printf("encoding coeff %d xb,yb=%d,%d: %d\n", y*8+x, xb, yb, k);
- rans_encoder.encode_coeff(k);
- }
- if (yb % 16 == 8) {
- num_bytes += rans_encoder.save_block(codedfp);
+ for (unsigned block_idx = 0; block_idx < NUM_BLOCKS; ++block_idx) {
+ unsigned yb = block_idx / WIDTH_BLOCKS;
+ unsigned xb = block_idx % WIDTH_BLOCKS;
+
+ int k = coeff_y[(yb * 8 + y) * WIDTH + (xb * 8 + x)];
+ //printf("encoding coeff %d xb,yb=%d,%d: %d\n", y*8+x, xb, yb, k);
+ rans_encoder.encode_coeff(k);
+
+ if (block_idx % BLOCKS_PER_STREAM == (BLOCKS_PER_STREAM - 1) || block_idx == NUM_BLOCKS - 1) {
+ int l = rans_encoder.save_block(codedfp);
+ num_bytes += l;
+ lens.push_back(l);
}
}
- if (HEIGHT % 16 != 0) {
- num_bytes += rans_encoder.save_block(codedfp);
- }
tot_bytes += num_bytes;
printf("coeff %d Y': %ld bytes\n", y * 8 + x, num_bytes);
+
+ double sum_l = 0.0;
+ for (int l : lens) {
+ sum_l += l;
+ }
+ double avg_l = sum_l / lens.size();
+
+ double sum_sql = 0.0;
+ for (int l : lens) {
+ sum_sql += (l - avg_l) * (l - avg_l);
+ }
+ double stddev_l = sqrt(sum_sql / (lens.size() - 1));
+ printf("coeff %d: avg=%.2f bytes, stddev=%.2f bytes\n", y*8+x, avg_l, stddev_l);
}
}
// Cb
for (unsigned y = 0; y < 8; ++y) {
for (unsigned x = 0; x < 8; ++x) {
- SymbolStats &s_chroma = stats[pick_stats_for(x, y) + 8];
- //SymbolStats &s_chroma = stats[pick_stats_for(x, y)];
+ SymbolStats &s_chroma = stats[pick_stats_for(x, y, true)];
rans_encoder.init_prob(s_chroma);
rans_encoder.clear();
size_t num_bytes = 0;
- for (unsigned yb = 0; yb < HEIGHT; yb += 8) {
- for (unsigned xb = 0; xb < WIDTH/2; xb += 8) {
- int k = coeff_cb[(yb + y) * WIDTH/2 + (xb + x)];
- rans_encoder.encode_coeff(k);
- }
- if (yb % 16 == 8) {
+ for (unsigned block_idx = 0; block_idx < NUM_BLOCKS_CHROMA; ++block_idx) {
+ unsigned yb = block_idx / WIDTH_BLOCKS_CHROMA;
+ unsigned xb = block_idx % WIDTH_BLOCKS_CHROMA;
+
+ int k = coeff_cb[(yb * 8 + y) * WIDTH/2 + (xb * 8 + x)];
+ //printf("encoding coeff %d xb,yb=%d,%d: %d\n", y*8+x, xb, yb, k);
+ rans_encoder.encode_coeff(k);
+
+ if (block_idx % BLOCKS_PER_STREAM == (BLOCKS_PER_STREAM - 1) || block_idx == NUM_BLOCKS - 1) {
num_bytes += rans_encoder.save_block(codedfp);
}
}
- if (HEIGHT % 16 != 0) {
- num_bytes += rans_encoder.save_block(codedfp);
- }
tot_bytes += num_bytes;
printf("coeff %d Cb: %ld bytes\n", y * 8 + x, num_bytes);
}
// Cr
for (unsigned y = 0; y < 8; ++y) {
for (unsigned x = 0; x < 8; ++x) {
- SymbolStats &s_chroma = stats[pick_stats_for(x, y) + 8];
- //SymbolStats &s_chroma = stats[pick_stats_for(x, y)];
+ SymbolStats &s_chroma = stats[pick_stats_for(x, y, true)];
rans_encoder.init_prob(s_chroma);
rans_encoder.clear();
size_t num_bytes = 0;
- for (unsigned yb = 0; yb < HEIGHT; yb += 8) {
- for (unsigned xb = 0; xb < WIDTH/2; xb += 8) {
- int k = coeff_cr[(yb + y) * WIDTH/2 + (xb + x)];
- rans_encoder.encode_coeff(k);
- }
- if (yb % 16 == 8) {
+ for (unsigned block_idx = 0; block_idx < NUM_BLOCKS_CHROMA; ++block_idx) {
+ unsigned yb = block_idx / WIDTH_BLOCKS_CHROMA;
+ unsigned xb = block_idx % WIDTH_BLOCKS_CHROMA;
+
+ int k = coeff_cr[(yb * 8 + y) * WIDTH/2 + (xb * 8 + x)];
+ //printf("encoding coeff %d xb,yb=%d,%d: %d\n", y*8+x, xb, yb, k);
+ rans_encoder.encode_coeff(k);
+
+ if (block_idx % BLOCKS_PER_STREAM == (BLOCKS_PER_STREAM - 1) || block_idx == NUM_BLOCKS - 1) {
num_bytes += rans_encoder.save_block(codedfp);
}
}
- if (HEIGHT % 16 != 0) {
- num_bytes += rans_encoder.save_block(codedfp);
- }
tot_bytes += num_bytes;
printf("coeff %d Cr: %ld bytes\n", y * 8 + x, num_bytes);
}
}
- printf("%ld bytes + %ld sign bits (%ld) + %ld escape bits (%ld) = %ld total bytes\n",
- tot_bytes - sign_bits / 8 - extra_bits / 8,
- sign_bits,
- sign_bits / 8,
+ printf("%ld bytes + %ld escape bits (%ld) = %ld total bytes\n",
+ tot_bytes - extra_bits / 8,
extra_bits,
extra_bits / 8,
tot_bytes);
+
+#if 0
+ printf("Max coefficient ranges (as a function of x):\n\n");
+ for (unsigned x = 0; x < 8; ++x) {
+ int range = std::max(max_val_x[x], -min_val_x[x]);
+ printf(" [%4d, %4d] (%.2f bits)\n", min_val_x[x], max_val_x[x], log2(range * 2 + 1));
+ }
+
+ printf("Max coefficient ranges (as a function of y):\n\n");
+ for (unsigned y = 0; y < 8; ++y) {
+ int range = std::max(max_val_y[y], -min_val_y[y]);
+ printf(" [%4d, %4d] (%.2f bits)\n", min_val_y[y], max_val_y[y], log2(range * 2 + 1));
+ }
+#endif
}