diff options
Diffstat (limited to 'third_party/aom/av1/encoder/subexp.c')
-rw-r--r-- | third_party/aom/av1/encoder/subexp.c | 282 |
1 files changed, 282 insertions, 0 deletions
diff --git a/third_party/aom/av1/encoder/subexp.c b/third_party/aom/av1/encoder/subexp.c new file mode 100644 index 000000000..8960d3341 --- /dev/null +++ b/third_party/aom/av1/encoder/subexp.c @@ -0,0 +1,282 @@ +/* + * Copyright (c) 2016, Alliance for Open Media. All rights reserved + * + * This source code is subject to the terms of the BSD 2 Clause License and + * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License + * was not distributed with this source code in the LICENSE file, you can + * obtain it at www.aomedia.org/license/software. If the Alliance for Open + * Media Patent License 1.0 was not distributed with this source code in the + * PATENTS file, you can obtain it at www.aomedia.org/license/patent. + */ +#include "aom_dsp/bitwriter.h" + +#include "av1/common/common.h" +#include "av1/common/entropy.h" +#include "av1/encoder/cost.h" +#include "av1/encoder/subexp.h" + +static const uint8_t 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, 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, 0, +}; +#define MIN_DELP_BITS 5 + +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 uint8_t 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(aom_prob newp, aom_prob oldp) { + int delp = remap_prob(newp, oldp); + return update_bits[delp] << AV1_PROB_COST_SHIFT; +} + +static void encode_uniform(aom_writer *w, int v) { + const int l = 8; + const int m = (1 << l) - 190; + if (v < m) { + aom_write_literal(w, v, l - 1); + } else { + aom_write_literal(w, m + ((v - m) >> 1), l - 1); + aom_write_literal(w, (v - m) & 1, 1); + } +} + +static INLINE int write_bit_gte(aom_writer *w, int word, int test) { + aom_write_literal(w, word >= test, 1); + return word >= test; +} + +static void encode_term_subexp(aom_writer *w, int word) { + if (!write_bit_gte(w, word, 16)) { + aom_write_literal(w, word, 4); + } else if (!write_bit_gte(w, word, 32)) { + aom_write_literal(w, word - 16, 4); + } else if (!write_bit_gte(w, word, 64)) { + aom_write_literal(w, word - 32, 5); + } else { + encode_uniform(w, word - 64); + } +} + +void av1_write_prob_diff_update(aom_writer *w, aom_prob newp, aom_prob oldp) { + const int delp = remap_prob(newp, oldp); + encode_term_subexp(w, delp); +} + +int av1_prob_diff_update_savings_search(const unsigned int *ct, aom_prob oldp, + aom_prob *bestp, aom_prob upd, + int probwt) { + const uint32_t old_b = cost_branch256(ct, oldp); + int bestsavings = 0; + aom_prob newp, bestnewp = oldp; + const int step = *bestp > oldp ? -1 : 1; + const int upd_cost = av1_cost_one(upd) - av1_cost_zero(upd); + + if (old_b > (uint32_t)upd_cost + (MIN_DELP_BITS << AV1_PROB_COST_SHIFT)) { + 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) + upd_cost; + const int savings = (int)((int64_t)old_b - new_b - update_b * probwt); + if (savings > bestsavings) { + bestsavings = savings; + bestnewp = newp; + } + } + } + *bestp = bestnewp; + return bestsavings; +} + +int av1_prob_diff_update_savings_search_model(const unsigned int *ct, + const aom_prob oldp, + aom_prob *bestp, aom_prob upd, + int stepsize, int probwt) { + int i, old_b, new_b, update_b, savings, bestsavings; + int newp; + const int step_sign = *bestp > oldp ? -1 : 1; + const int step = stepsize * step_sign; + const int upd_cost = av1_cost_one(upd) - av1_cost_zero(upd); + const aom_prob *newplist, *oldplist; + aom_prob bestnewp; + oldplist = av1_pareto8_full[oldp - 1]; + old_b = cost_branch256(ct + 2 * PIVOT_NODE, oldp); + for (i = UNCONSTRAINED_NODES; i < ENTROPY_NODES; ++i) + old_b += cost_branch256(ct + 2 * i, oldplist[i - UNCONSTRAINED_NODES]); + + bestsavings = 0; + bestnewp = oldp; + + assert(stepsize > 0); + + if (old_b > upd_cost + (MIN_DELP_BITS << AV1_PROB_COST_SHIFT)) { + for (newp = *bestp; (newp - oldp) * step_sign < 0; newp += step) { + if (newp < 1 || newp > 255) continue; + newplist = av1_pareto8_full[newp - 1]; + new_b = cost_branch256(ct + 2 * PIVOT_NODE, newp); + for (i = UNCONSTRAINED_NODES; i < ENTROPY_NODES; ++i) + new_b += cost_branch256(ct + 2 * i, newplist[i - UNCONSTRAINED_NODES]); + update_b = prob_diff_update_cost(newp, oldp) + upd_cost; + savings = old_b - new_b - update_b * probwt; + if (savings > bestsavings) { + bestsavings = savings; + bestnewp = newp; + } + } + } + + *bestp = bestnewp; + return bestsavings; +} + +#if CONFIG_SUBFRAME_PROB_UPDATE +static int get_cost(unsigned int ct[][2], aom_prob p, int n) { + int i, p0 = p; + unsigned int total_ct[2] = { 0, 0 }; + int cost = 0; + + for (i = 0; i <= n; ++i) { + cost += cost_branch256(ct[i], p); + total_ct[0] += ct[i][0]; + total_ct[1] += ct[i][1]; + if (i < n) + p = av1_merge_probs(p0, total_ct, COEF_COUNT_SAT, COEF_MAX_UPDATE_FACTOR); + } + return cost; +} + +int av1_prob_update_search_subframe(unsigned int ct[][2], aom_prob oldp, + aom_prob *bestp, aom_prob upd, int n) { + const int old_b = get_cost(ct, oldp, n); + int bestsavings = 0; + const int upd_cost = av1_cost_one(upd) - av1_cost_zero(upd); + aom_prob newp, bestnewp = oldp; + const int step = *bestp > oldp ? -1 : 1; + + for (newp = *bestp; newp != oldp; newp += step) { + const int new_b = get_cost(ct, newp, n); + const int update_b = prob_diff_update_cost(newp, oldp) + upd_cost; + const int savings = old_b - new_b - update_b; + if (savings > bestsavings) { + bestsavings = savings; + bestnewp = newp; + } + } + *bestp = bestnewp; + return bestsavings; +} + +int av1_prob_update_search_model_subframe( + unsigned int ct[ENTROPY_NODES][COEF_PROBS_BUFS][2], const aom_prob *oldp, + aom_prob *bestp, aom_prob upd, int stepsize, int n) { + int i, old_b, new_b, update_b, savings, bestsavings; + int newp; + const int step_sign = *bestp > oldp[PIVOT_NODE] ? -1 : 1; + const int step = stepsize * step_sign; + const int upd_cost = av1_cost_one(upd) - av1_cost_zero(upd); + aom_prob bestnewp, newplist[ENTROPY_NODES], oldplist[ENTROPY_NODES]; + av1_model_to_full_probs(oldp, oldplist); + memcpy(newplist, oldp, sizeof(aom_prob) * UNCONSTRAINED_NODES); + for (i = UNCONSTRAINED_NODES, old_b = 0; i < ENTROPY_NODES; ++i) + old_b += get_cost(ct[i], oldplist[i], n); + old_b += get_cost(ct[PIVOT_NODE], oldplist[PIVOT_NODE], n); + + bestsavings = 0; + bestnewp = oldp[PIVOT_NODE]; + + assert(stepsize > 0); + + for (newp = *bestp; (newp - oldp[PIVOT_NODE]) * step_sign < 0; newp += step) { + if (newp < 1 || newp > 255) continue; + newplist[PIVOT_NODE] = newp; + av1_model_to_full_probs(newplist, newplist); + for (i = UNCONSTRAINED_NODES, new_b = 0; i < ENTROPY_NODES; ++i) + new_b += get_cost(ct[i], newplist[i], n); + new_b += get_cost(ct[PIVOT_NODE], newplist[PIVOT_NODE], n); + update_b = prob_diff_update_cost(newp, oldp[PIVOT_NODE]) + upd_cost; + savings = old_b - new_b - update_b; + if (savings > bestsavings) { + bestsavings = savings; + bestnewp = newp; + } + } + + *bestp = bestnewp; + return bestsavings; +} +#endif // CONFIG_SUBFRAME_PROB_UPDATE + +void av1_cond_prob_diff_update(aom_writer *w, aom_prob *oldp, + const unsigned int ct[2], int probwt) { + const aom_prob upd = DIFF_UPDATE_PROB; + aom_prob newp = get_binary_prob(ct[0], ct[1]); + const int savings = + av1_prob_diff_update_savings_search(ct, *oldp, &newp, upd, probwt); + assert(newp >= 1); + if (savings > 0) { + aom_write(w, 1, upd); + av1_write_prob_diff_update(w, newp, *oldp); + *oldp = newp; + } else { + aom_write(w, 0, upd); + } +} + +int av1_cond_prob_diff_update_savings(aom_prob *oldp, const unsigned int ct[2], + int probwt) { + const aom_prob upd = DIFF_UPDATE_PROB; + aom_prob newp = get_binary_prob(ct[0], ct[1]); + const int savings = + av1_prob_diff_update_savings_search(ct, *oldp, &newp, upd, probwt); + return savings; +} |