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-rw-r--r--media/libvpx/vp9/encoder/vp9_subexp.c214
1 files changed, 214 insertions, 0 deletions
diff --git a/media/libvpx/vp9/encoder/vp9_subexp.c b/media/libvpx/vp9/encoder/vp9_subexp.c
new file mode 100644
index 0000000000..b345b162cd
--- /dev/null
+++ b/media/libvpx/vp9/encoder/vp9_subexp.c
@@ -0,0 +1,214 @@
+/*
+ * Copyright (c) 2013 The WebM project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "vp9/common/vp9_common.h"
+#include "vp9/common/vp9_entropy.h"
+
+#include "vp9/encoder/vp9_cost.h"
+#include "vp9/encoder/vp9_subexp.h"
+#include "vp9/encoder/vp9_writer.h"
+
+#define vp9_cost_upd256 ((int)(vp9_cost_one(upd) - vp9_cost_zero(upd)))
+
+static const int update_bits[255] = {
+ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
+ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
+ 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+ 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+ 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+ 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10,
+ 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
+ 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
+ 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
+ 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
+ 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
+ 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
+ 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11,
+ 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 0,
+};
+
+static int recenter_nonneg(int v, int m) {
+ if (v > (m << 1))
+ return v;
+ else if (v >= m)
+ return ((v - m) << 1);
+ else
+ return ((m - v) << 1) - 1;
+}
+
+static int remap_prob(int v, int m) {
+ int i;
+ static const int map_table[MAX_PROB - 1] = {
+ // generated by:
+ // map_table[j] = split_index(j, MAX_PROB - 1, MODULUS_PARAM);
+ 20, 21, 22, 23, 24, 25, 0, 26, 27, 28, 29, 30, 31, 32, 33,
+ 34, 35, 36, 37, 1, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
+ 48, 49, 2, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61,
+ 3, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 4, 74,
+ 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 5, 86, 87, 88,
+ 89, 90, 91, 92, 93, 94, 95, 96, 97, 6, 98, 99, 100, 101, 102,
+ 103, 104, 105, 106, 107, 108, 109, 7, 110, 111, 112, 113, 114, 115, 116,
+ 117, 118, 119, 120, 121, 8, 122, 123, 124, 125, 126, 127, 128, 129, 130,
+ 131, 132, 133, 9, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144,
+ 145, 10, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 11,
+ 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 12, 170, 171,
+ 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 13, 182, 183, 184, 185,
+ 186, 187, 188, 189, 190, 191, 192, 193, 14, 194, 195, 196, 197, 198, 199,
+ 200, 201, 202, 203, 204, 205, 15, 206, 207, 208, 209, 210, 211, 212, 213,
+ 214, 215, 216, 217, 16, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227,
+ 228, 229, 17, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 240, 241,
+ 18, 242, 243, 244, 245, 246, 247, 248, 249, 250, 251, 252, 253, 19,
+ };
+ v--;
+ m--;
+ if ((m << 1) <= MAX_PROB)
+ i = recenter_nonneg(v, m) - 1;
+ else
+ i = recenter_nonneg(MAX_PROB - 1 - v, MAX_PROB - 1 - m) - 1;
+
+ i = map_table[i];
+ return i;
+}
+
+static int prob_diff_update_cost(vp9_prob newp, vp9_prob oldp) {
+ int delp = remap_prob(newp, oldp);
+ return update_bits[delp] * 256;
+}
+
+static void encode_uniform(vp9_writer *w, int v) {
+ const int l = 8;
+ const int m = (1 << l) - 191;
+ if (v < m) {
+ vp9_write_literal(w, v, l - 1);
+ } else {
+ vp9_write_literal(w, m + ((v - m) >> 1), l - 1);
+ vp9_write_literal(w, (v - m) & 1, 1);
+ }
+}
+
+static INLINE int write_bit_gte(vp9_writer *w, int word, int test) {
+ vp9_write_literal(w, word >= test, 1);
+ return word >= test;
+}
+
+static void encode_term_subexp(vp9_writer *w, int word) {
+ if (!write_bit_gte(w, word, 16)) {
+ vp9_write_literal(w, word, 4);
+ } else if (!write_bit_gte(w, word, 32)) {
+ vp9_write_literal(w, word - 16, 4);
+ } else if (!write_bit_gte(w, word, 64)) {
+ vp9_write_literal(w, word - 32, 5);
+ } else {
+ encode_uniform(w, word - 64);
+ }
+}
+
+void vp9_write_prob_diff_update(vp9_writer *w, vp9_prob newp, vp9_prob oldp) {
+ const int delp = remap_prob(newp, oldp);
+ encode_term_subexp(w, delp);
+}
+
+int vp9_prob_diff_update_savings_search(const unsigned int *ct,
+ vp9_prob oldp, vp9_prob *bestp,
+ vp9_prob upd) {
+ const int old_b = cost_branch256(ct, oldp);
+ int bestsavings = 0;
+ vp9_prob newp, bestnewp = oldp;
+ const int step = *bestp > oldp ? -1 : 1;
+
+ for (newp = *bestp; newp != oldp; newp += step) {
+ const int new_b = cost_branch256(ct, newp);
+ const int update_b = prob_diff_update_cost(newp, oldp) + vp9_cost_upd256;
+ const int savings = old_b - new_b - update_b;
+ if (savings > bestsavings) {
+ bestsavings = savings;
+ bestnewp = newp;
+ }
+ }
+ *bestp = bestnewp;
+ return bestsavings;
+}
+
+int vp9_prob_diff_update_savings_search_model(const unsigned int *ct,
+ const vp9_prob *oldp,
+ vp9_prob *bestp,
+ vp9_prob upd,
+ int stepsize) {
+ int i, old_b, new_b, update_b, savings, bestsavings, step;
+ int newp;
+ vp9_prob bestnewp, newplist[ENTROPY_NODES], oldplist[ENTROPY_NODES];
+ vp9_model_to_full_probs(oldp, oldplist);
+ memcpy(newplist, oldp, sizeof(vp9_prob) * UNCONSTRAINED_NODES);
+ for (i = UNCONSTRAINED_NODES, old_b = 0; i < ENTROPY_NODES; ++i)
+ old_b += cost_branch256(ct + 2 * i, oldplist[i]);
+ old_b += cost_branch256(ct + 2 * PIVOT_NODE, oldplist[PIVOT_NODE]);
+
+ bestsavings = 0;
+ bestnewp = oldp[PIVOT_NODE];
+
+ if (*bestp > oldp[PIVOT_NODE]) {
+ step = -stepsize;
+ for (newp = *bestp; newp > oldp[PIVOT_NODE]; newp += step) {
+ if (newp < 1 || newp > 255)
+ continue;
+ newplist[PIVOT_NODE] = newp;
+ vp9_model_to_full_probs(newplist, newplist);
+ for (i = UNCONSTRAINED_NODES, new_b = 0; i < ENTROPY_NODES; ++i)
+ new_b += cost_branch256(ct + 2 * i, newplist[i]);
+ new_b += cost_branch256(ct + 2 * PIVOT_NODE, newplist[PIVOT_NODE]);
+ update_b = prob_diff_update_cost(newp, oldp[PIVOT_NODE]) +
+ vp9_cost_upd256;
+ savings = old_b - new_b - update_b;
+ if (savings > bestsavings) {
+ bestsavings = savings;
+ bestnewp = newp;
+ }
+ }
+ } else {
+ step = stepsize;
+ for (newp = *bestp; newp < oldp[PIVOT_NODE]; newp += step) {
+ if (newp < 1 || newp > 255)
+ continue;
+ newplist[PIVOT_NODE] = newp;
+ vp9_model_to_full_probs(newplist, newplist);
+ for (i = UNCONSTRAINED_NODES, new_b = 0; i < ENTROPY_NODES; ++i)
+ new_b += cost_branch256(ct + 2 * i, newplist[i]);
+ new_b += cost_branch256(ct + 2 * PIVOT_NODE, newplist[PIVOT_NODE]);
+ update_b = prob_diff_update_cost(newp, oldp[PIVOT_NODE]) +
+ vp9_cost_upd256;
+ savings = old_b - new_b - update_b;
+ if (savings > bestsavings) {
+ bestsavings = savings;
+ bestnewp = newp;
+ }
+ }
+ }
+
+ *bestp = bestnewp;
+ return bestsavings;
+}
+
+void vp9_cond_prob_diff_update(vp9_writer *w, vp9_prob *oldp,
+ const unsigned int ct[2]) {
+ const vp9_prob upd = DIFF_UPDATE_PROB;
+ vp9_prob newp = get_binary_prob(ct[0], ct[1]);
+ const int savings = vp9_prob_diff_update_savings_search(ct, *oldp, &newp,
+ upd);
+ assert(newp >= 1);
+ if (savings > 0) {
+ vp9_write(w, 1, upd);
+ vp9_write_prob_diff_update(w, newp, *oldp);
+ *oldp = newp;
+ } else {
+ vp9_write(w, 0, upd);
+ }
+}
generated by cgit v1.2.3 (git 2.26.2) at 2024-11-20 17:26:04 +0000