Add an implementation of Asymetric Numeral Systems (ANS).
Change-Id: Ie41bc72127e700887566dcc951da9d83a0b94891
This commit is contained in:
Alex Converse
Родитель
387a10e3dc
Коммит
9ffcb469fb
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@ -281,6 +281,7 @@ EXPERIMENT_LIST="
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ext_interp
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ext_refs
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supertx
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ans
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"
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CONFIG_LIST="
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dependency_tracking
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@ -165,6 +165,7 @@ ifeq ($(CONFIG_VP10),yes)
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LIBVPX_TEST_SRCS-yes += vp10_inv_txfm_test.cc
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LIBVPX_TEST_SRCS-$(CONFIG_VP10_ENCODER) += vp10_dct_test.cc
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LIBVPX_TEST_SRCS-$(CONFIG_ANS) += vp10_ans_test.cc
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endif # VP10
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@ -0,0 +1,337 @@
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/*
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* Copyright (c) 2015 The WebM project authors. All Rights Reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* that can be found in the LICENSE file in the root of the source
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* tree. An additional intellectual property rights grant can be found
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* in the file PATENTS. All contributing project authors may
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* be found in the AUTHORS file in the root of the source tree.
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*/
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#include <assert.h>
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#include <math.h>
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#include <stdio.h>
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#include <ctime>
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#include <utility>
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#include <vector>
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#include "third_party/googletest/src/include/gtest/gtest.h"
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#include "test/acm_random.h"
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#include "vp10/common/ans.h"
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#include "vp10/encoder/treewriter.h"
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#include "vpx_dsp/bitreader.h"
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#include "vpx_dsp/bitwriter.h"
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namespace {
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typedef std::vector<std::pair<uint8_t, bool> > PvVec;
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PvVec abs_encode_build_vals(int iters) {
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PvVec ret;
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libvpx_test::ACMRandom gen(0x30317076);
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double entropy = 0;
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for (int i = 0; i < iters; ++i) {
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uint8_t p;
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do {
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p = gen.Rand8();
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} while (p == 0); // zero is not a valid coding probability
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bool b = gen.Rand8() < p;
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ret.push_back(std::make_pair(static_cast<uint8_t>(p), b));
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double d = p / 256.;
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entropy += -d * log2(d) - (1 - d) * log2(1 - d);
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}
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printf("entropy %f\n", entropy);
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return ret;
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}
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bool check_rabs(const PvVec &pv_vec, uint8_t *buf) {
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AnsCoder a;
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ans_write_init(&a, buf);
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std::clock_t start = std::clock();
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for (PvVec::const_reverse_iterator it = pv_vec.rbegin(); it != pv_vec.rend();
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++it) {
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rabs_write(&a, it->second, 256 - it->first);
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}
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std::clock_t enc_time = std::clock() - start;
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int offset = ans_write_end(&a);
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bool okay = true;
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AnsDecoder d;
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if (ans_read_init(&d, buf, offset)) return false;
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start = std::clock();
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for (PvVec::const_iterator it = pv_vec.begin(); it != pv_vec.end(); ++it) {
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okay &= rabs_read(&d, 256 - it->first) == it->second;
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}
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std::clock_t dec_time = std::clock() - start;
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if (!okay) return false;
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printf("rABS size %d enc_time %f dec_time %f\n", offset,
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static_cast<float>(enc_time) / CLOCKS_PER_SEC,
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static_cast<float>(dec_time) / CLOCKS_PER_SEC);
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return ans_read_end(&d);
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}
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bool check_rabs_asc(const PvVec &pv_vec, uint8_t *buf) {
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AnsCoder a;
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ans_write_init(&a, buf);
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std::clock_t start = std::clock();
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for (PvVec::const_reverse_iterator it = pv_vec.rbegin(); it != pv_vec.rend();
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++it) {
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rabs_asc_write(&a, it->second, 256 - it->first);
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}
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std::clock_t enc_time = std::clock() - start;
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int offset = ans_write_end(&a);
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bool okay = true;
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AnsDecoder d;
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if (ans_read_init(&d, buf, offset)) return false;
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start = std::clock();
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for (PvVec::const_iterator it = pv_vec.begin(); it != pv_vec.end(); ++it) {
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okay &= rabs_asc_read(&d, 256 - it->first) == it->second;
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}
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std::clock_t dec_time = std::clock() - start;
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if (!okay) return false;
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printf("rABS (asc) size %d enc_time %f dec_time %f\n", offset,
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static_cast<float>(enc_time) / CLOCKS_PER_SEC,
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static_cast<float>(dec_time) / CLOCKS_PER_SEC);
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return ans_read_end(&d);
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}
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bool check_uabs(const PvVec &pv_vec, uint8_t *buf) {
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AnsCoder a;
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ans_write_init(&a, buf);
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std::clock_t start = std::clock();
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for (PvVec::const_reverse_iterator it = pv_vec.rbegin(); it != pv_vec.rend();
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++it) {
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uabs_write(&a, it->second, 256 - it->first);
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}
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std::clock_t enc_time = std::clock() - start;
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int offset = ans_write_end(&a);
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bool okay = true;
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AnsDecoder d;
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if (ans_read_init(&d, buf, offset)) return false;
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start = std::clock();
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for (PvVec::const_iterator it = pv_vec.begin(); it != pv_vec.end(); ++it) {
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okay &= uabs_read(&d, 256 - it->first) == it->second;
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}
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std::clock_t dec_time = std::clock() - start;
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if (!okay) return false;
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printf("uABS size %d enc_time %f dec_time %f\n", offset,
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static_cast<float>(enc_time) / CLOCKS_PER_SEC,
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static_cast<float>(dec_time) / CLOCKS_PER_SEC);
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return ans_read_end(&d);
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}
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bool check_vpxbool(const PvVec &pv_vec, uint8_t *buf) {
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vpx_writer w;
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vpx_reader r;
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vpx_start_encode(&w, buf);
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std::clock_t start = std::clock();
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for (PvVec::const_iterator it = pv_vec.begin(); it != pv_vec.end(); ++it) {
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vpx_write(&w, it->second, 256 - it->first);
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}
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std::clock_t enc_time = std::clock() - start;
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vpx_stop_encode(&w);
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bool okay = true;
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vpx_reader_init(&r, buf, w.pos, NULL, NULL);
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start = std::clock();
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for (PvVec::const_iterator it = pv_vec.begin(); it != pv_vec.end(); ++it) {
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okay &= vpx_read(&r, 256 - it->first) == it->second;
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}
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std::clock_t dec_time = std::clock() - start;
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printf("VPX size %d enc_time %f dec_time %f\n", w.pos,
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static_cast<float>(enc_time) / CLOCKS_PER_SEC,
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static_cast<float>(dec_time) / CLOCKS_PER_SEC);
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return okay;
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}
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const rans_sym rans_sym_tab[] = {
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{70, 186}, {70, 116}, {100, 16}, {16, 0},
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};
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const int kDistinctSyms = sizeof(rans_sym_tab) / sizeof(rans_sym_tab[0]);
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std::vector<int> ans_encode_build_vals(const rans_sym *tab, int iters) {
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std::vector<int> p_to_sym;
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int i = 0;
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while (p_to_sym.size() < 256) {
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p_to_sym.insert(p_to_sym.end(), tab[i].prob, i);
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++i;
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}
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assert(p_to_sym.size() == 256);
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std::vector<int> ret;
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libvpx_test::ACMRandom gen(18543637);
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for (int i = 0; i < iters; ++i) {
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int sym = p_to_sym[gen.Rand8()];
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ret.push_back(sym);
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}
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return ret;
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}
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void rans_build_dec_tab(const struct rans_sym sym_tab[],
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rans_dec_lut dec_tab) {
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int val = 0;
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int i;
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for (i = ans_p8_precision - 1; i >= 0; --i) {
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dec_tab[i].val = val;
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dec_tab[i].prob = sym_tab[val].prob;
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dec_tab[i].cum_prob = sym_tab[val].cum_prob;
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if (i == sym_tab[val].cum_prob) ++val;
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}
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}
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bool check_rans(const std::vector<int> &sym_vec, const rans_sym *const tab,
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uint8_t *buf) {
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AnsCoder a;
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ans_write_init(&a, buf);
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rans_dec_lut dec_tab;
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rans_build_dec_tab(tab, dec_tab);
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std::clock_t start = std::clock();
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for (std::vector<int>::const_reverse_iterator it = sym_vec.rbegin();
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it != sym_vec.rend(); ++it) {
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rans_write(&a, &tab[*it]);
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}
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std::clock_t enc_time = std::clock() - start;
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int offset = ans_write_end(&a);
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bool okay = true;
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AnsDecoder d;
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if (ans_read_init(&d, buf, offset)) return false;
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start = std::clock();
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for (std::vector<int>::const_iterator it = sym_vec.begin();
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it != sym_vec.end(); ++it) {
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okay &= rans_read(&d, dec_tab) == *it;
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}
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std::clock_t dec_time = std::clock() - start;
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if (!okay) return false;
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printf("rANS size %d enc_time %f dec_time %f\n", offset,
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static_cast<float>(enc_time) / CLOCKS_PER_SEC,
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static_cast<float>(dec_time) / CLOCKS_PER_SEC);
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return ans_read_end(&d);
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}
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void build_tree(vpx_tree_index *tree, int num_syms) {
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vpx_tree_index i;
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int sym = 0;
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for (i = 0; i < num_syms - 1; ++i) {
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tree[2 * i] = sym--;
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tree[2 * i + 1] = 2 * (i + 1);
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}
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tree[2 * i - 1] = sym;
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}
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// treep are the probabilites of tree nodes like:
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// *
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// / \
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// -sym0 *
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// / \
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// -sym1 *
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// / \
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// -sym2 -sym3
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void tab2tree(const rans_sym *tab, int tab_size, vpx_prob *treep) {
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const unsigned basep = 256;
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unsigned pleft = basep;
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for (int i = 0; i < tab_size - 1; ++i) {
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unsigned prob = (tab[i].prob * basep + (basep / 2)) / pleft;
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assert(prob > 0 && prob < 256);
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treep[i] = prob;
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pleft -= tab[i].prob;
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}
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}
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struct sym_bools {
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unsigned bits;
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int len;
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};
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static void make_tree_bits_tab(sym_bools *tab, int num_syms) {
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unsigned bits = 0;
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int len = 0;
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int i;
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for (i = 0; i < num_syms - 1; ++i) {
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bits *= 2;
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++len;
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tab[i].bits = bits;
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tab[i].len = len;
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++bits;
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}
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tab[i].bits = bits;
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tab[i].len = len;
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}
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void build_tpb(vpx_prob probs[/*num_syms*/],
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vpx_tree_index tree[/*2*num_syms*/],
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sym_bools bit_len[/*num_syms*/],
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const rans_sym sym_tab[/*num_syms*/], int num_syms) {
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tab2tree(sym_tab, num_syms, probs);
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build_tree(tree, num_syms);
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make_tree_bits_tab(bit_len, num_syms);
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}
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bool check_vpxtree(const std::vector<int> &sym_vec, const rans_sym *sym_tab,
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uint8_t *buf) {
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vpx_writer w;
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vpx_reader r;
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vpx_start_encode(&w, buf);
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vpx_prob probs[kDistinctSyms];
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vpx_tree_index tree[2 * kDistinctSyms];
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sym_bools bit_len[kDistinctSyms];
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build_tpb(probs, tree, bit_len, sym_tab, kDistinctSyms);
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std::clock_t start = std::clock();
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for (std::vector<int>::const_iterator it = sym_vec.begin();
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it != sym_vec.end(); ++it) {
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vp10_write_tree(&w, tree, probs, bit_len[*it].bits, bit_len[*it].len, 0);
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}
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std::clock_t enc_time = std::clock() - start;
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vpx_stop_encode(&w);
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vpx_reader_init(&r, buf, w.pos, NULL, NULL);
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start = std::clock();
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for (std::vector<int>::const_iterator it = sym_vec.begin();
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it != sym_vec.end(); ++it) {
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if (vpx_read_tree(&r, tree, probs) != *it) return false;
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}
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std::clock_t dec_time = std::clock() - start;
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printf("VPXtree size %u enc_time %f dec_time %f\n", w.pos,
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static_cast<float>(enc_time) / CLOCKS_PER_SEC,
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static_cast<float>(dec_time) / CLOCKS_PER_SEC);
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return true;
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}
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class Vp10AbsTest : public ::testing::Test {
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protected:
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static void SetUpTestCase() { pv_vec_ = abs_encode_build_vals(kNumBools); }
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virtual void SetUp() { buf_ = new uint8_t[kNumBools / 8]; }
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virtual void TearDown() { delete[] buf_; }
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static const int kNumBools = 100000000;
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static PvVec pv_vec_;
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uint8_t *buf_;
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};
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PvVec Vp10AbsTest::pv_vec_;
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class Vp10AnsTest : public ::testing::Test {
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protected:
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static void SetUpTestCase() {
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sym_vec_ = ans_encode_build_vals(rans_sym_tab, kNumSyms);
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}
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virtual void SetUp() { buf_ = new uint8_t[kNumSyms / 2]; }
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virtual void TearDown() { delete[] buf_; }
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static const int kNumSyms = 25000000;
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static std::vector<int> sym_vec_;
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uint8_t *buf_;
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};
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std::vector<int> Vp10AnsTest::sym_vec_;
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TEST_F(Vp10AbsTest, Vpxbool) { EXPECT_TRUE(check_vpxbool(pv_vec_, buf_)); }
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TEST_F(Vp10AbsTest, Rabs) { EXPECT_TRUE(check_rabs(pv_vec_, buf_)); }
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TEST_F(Vp10AbsTest, RabsAsc) { EXPECT_TRUE(check_rabs_asc(pv_vec_, buf_)); }
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TEST_F(Vp10AbsTest, Uabs) { EXPECT_TRUE(check_uabs(pv_vec_, buf_)); }
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TEST_F(Vp10AnsTest, Rans) {
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EXPECT_TRUE(check_rans(sym_vec_, rans_sym_tab, buf_));
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}
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TEST_F(Vp10AnsTest, Vpxtree) {
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EXPECT_TRUE(check_vpxtree(sym_vec_, rans_sym_tab, buf_));
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}
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} // namespace
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@ -0,0 +1,299 @@
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/*
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* Copyright (c) 2015 The WebM project authors. All Rights Reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* 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
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* be found in the AUTHORS file in the root of the source tree.
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*/
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#ifndef VP10_COMMON_ANS_H_
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#define VP10_COMMON_ANS_H_
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// An implementation of Asymmetric Numeral Systems
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// http://arxiv.org/abs/1311.2540v2
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#include "./vpx_config.h"
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#include "vpx/vpx_integer.h"
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#include "vpx_ports/mem_ops.h"
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#define ANS_DIVIDE_BY_MULTIPLY 1
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#if ANS_DIVIDE_BY_MULTIPLY
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#include "vp10/common/divide.h"
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#define ANS_DIVREM(quotient, remainder, dividend, divisor) \
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do { \
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quotient = fastdiv(dividend, divisor); \
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remainder = dividend - quotient * divisor; \
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} while (0)
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#define ANS_DIV(dividend, divisor) \
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fastdiv(dividend, divisor)
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#else
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#define ANS_DIVREM(quotient, remainder, dividend, divisor) \
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do { \
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quotient = dividend / divisor; \
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remainder = dividend % divisor; \
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} while (0)
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#define ANS_DIV(dividend, divisor) \
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((dividend) / (divisor))
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#endif
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#ifdef __cplusplus
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extern "C" {
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#endif // __cplusplus
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struct AnsCoder {
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uint8_t *buf;
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int buf_offset;
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uint32_t state;
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};
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struct AnsDecoder {
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const uint8_t *buf;
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int buf_offset;
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uint32_t state;
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};
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typedef uint8_t AnsP8;
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#define ans_p8_precision 256u
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#define ans_p8_shift 8
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#define l_base (ans_p8_precision * 4) // l_base % precision must be 0
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#define io_base 256
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// Range I = { l_base, l_base + 1, ..., l_base * io_base - 1 }
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static INLINE void ans_write_init(struct AnsCoder *const ans,
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uint8_t *const buf) {
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ans->buf = buf;
|
||||
ans->buf_offset = 0;
|
||||
ans->state = l_base;
|
||||
}
|
||||
|
||||
static INLINE int ans_write_end(struct AnsCoder *const ans) {
|
||||
mem_put_le24(ans->buf + ans->buf_offset, ans->state);
|
||||
return ans->buf_offset + 3;
|
||||
}
|
||||
|
||||
// rABS with descending spread
|
||||
// p or p0 takes the place of l_s from the paper
|
||||
// ans_p8_precision is m
|
||||
static INLINE void rabs_desc_write(struct AnsCoder *ans, int val, AnsP8 p0) {
|
||||
const AnsP8 p = ans_p8_precision - p0;
|
||||
const unsigned l_s = val ? p : p0;
|
||||
unsigned quot, rem;
|
||||
if (ans->state >= l_base / ans_p8_precision * io_base * l_s) {
|
||||
ans->buf[ans->buf_offset++] = ans->state % io_base;
|
||||
ans->state /= io_base;
|
||||
}
|
||||
ANS_DIVREM(quot, rem, ans->state, l_s);
|
||||
ans->state = quot * ans_p8_precision + rem + (val ? 0 : p);
|
||||
}
|
||||
|
||||
#define ANS_IMPL1 0
|
||||
#define UNPREDICTABLE(x) x
|
||||
static INLINE int rabs_desc_read(struct AnsDecoder *ans, AnsP8 p0) {
|
||||
int val;
|
||||
#if ANS_IMPL1
|
||||
unsigned l_s;
|
||||
#else
|
||||
unsigned quot, rem, x, xn;
|
||||
#endif
|
||||
const AnsP8 p = ans_p8_precision - p0;
|
||||
if (ans->state < l_base) {
|
||||
ans->state = ans->state * io_base + ans->buf[--ans->buf_offset];
|
||||
}
|
||||
#if ANS_IMPL1
|
||||
val = ans->state % ans_p8_precision < p;
|
||||
l_s = val ? p : p0;
|
||||
ans->state = (ans->state / ans_p8_precision) * l_s +
|
||||
ans->state % ans_p8_precision - (!val * p);
|
||||
#else
|
||||
x = ans->state;
|
||||
quot = x / ans_p8_precision;
|
||||
rem = x % ans_p8_precision;
|
||||
xn = quot * p;
|
||||
val = rem < p;
|
||||
if (UNPREDICTABLE(val)) {
|
||||
ans->state = xn + rem;
|
||||
} else {
|
||||
// ans->state = quot * p0 + rem - p;
|
||||
ans->state = x - xn - p;
|
||||
}
|
||||
#endif
|
||||
return val;
|
||||
}
|
||||
|
||||
// rABS with ascending spread
|
||||
// p or p0 takes the place of l_s from the paper
|
||||
// ans_p8_precision is m
|
||||
static INLINE void rabs_asc_write(struct AnsCoder *ans, int val, AnsP8 p0) {
|
||||
const AnsP8 p = ans_p8_precision - p0;
|
||||
const unsigned l_s = val ? p : p0;
|
||||
unsigned quot, rem;
|
||||
if (ans->state >= l_base / ans_p8_precision * io_base * l_s) {
|
||||
ans->buf[ans->buf_offset++] = ans->state % io_base;
|
||||
ans->state /= io_base;
|
||||
}
|
||||
ANS_DIVREM(quot, rem, ans->state, l_s);
|
||||
ans->state = quot * ans_p8_precision + rem + (val ? p0 : 0);
|
||||
}
|
||||
|
||||
static INLINE int rabs_asc_read(struct AnsDecoder *ans, AnsP8 p0) {
|
||||
int val;
|
||||
#if ANS_IMPL1
|
||||
unsigned l_s;
|
||||
#else
|
||||
unsigned quot, rem, x, xn;
|
||||
#endif
|
||||
const AnsP8 p = ans_p8_precision - p0;
|
||||
if (ans->state < l_base) {
|
||||
ans->state = ans->state * io_base + ans->buf[--ans->buf_offset];
|
||||
}
|
||||
#if ANS_IMPL1
|
||||
val = ans->state % ans_p8_precision < p;
|
||||
l_s = val ? p : p0;
|
||||
ans->state = (ans->state / ans_p8_precision) * l_s +
|
||||
ans->state % ans_p8_precision - (!val * p);
|
||||
#else
|
||||
x = ans->state;
|
||||
quot = x / ans_p8_precision;
|
||||
rem = x % ans_p8_precision;
|
||||
xn = quot * p;
|
||||
val = rem >= p0;
|
||||
if (UNPREDICTABLE(val)) {
|
||||
ans->state = xn + rem - p0;
|
||||
} else {
|
||||
// ans->state = quot * p0 + rem - p0;
|
||||
ans->state = x - xn;
|
||||
}
|
||||
#endif
|
||||
return val;
|
||||
}
|
||||
|
||||
#define rabs_read rabs_desc_read
|
||||
#define rabs_write rabs_desc_write
|
||||
|
||||
// uABS with normalization
|
||||
static INLINE void uabs_write(struct AnsCoder *ans, int val, AnsP8 p0) {
|
||||
AnsP8 p = ans_p8_precision - p0;
|
||||
const unsigned l_s = val ? p : p0;
|
||||
if (ans->state >= l_base / ans_p8_precision * io_base * l_s) {
|
||||
ans->buf[ans->buf_offset++] = ans->state % io_base;
|
||||
ans->state /= io_base;
|
||||
}
|
||||
if (!val)
|
||||
ans->state = ANS_DIV(ans->state * ans_p8_precision, p0);
|
||||
else
|
||||
ans->state = ANS_DIV((ans->state + 1) * ans_p8_precision + p - 1, p) - 1;
|
||||
}
|
||||
|
||||
static INLINE int uabs_read(struct AnsDecoder *ans, AnsP8 p0) {
|
||||
AnsP8 p = ans_p8_precision - p0;
|
||||
int s;
|
||||
// unsigned int xp1;
|
||||
unsigned xp, sp;
|
||||
unsigned state = ans->state;
|
||||
if (state < l_base && ans->buf_offset > 0) {
|
||||
state = state * io_base + ans->buf[--ans->buf_offset];
|
||||
}
|
||||
sp = state * p;
|
||||
// xp1 = (sp + p) / ans_p8_precision;
|
||||
xp = sp / ans_p8_precision;
|
||||
// s = xp1 - xp;
|
||||
s = (sp & 0xFF) >= p0;
|
||||
if (UNPREDICTABLE(s))
|
||||
ans->state = xp;
|
||||
else
|
||||
ans->state = state - xp;
|
||||
return s;
|
||||
}
|
||||
|
||||
static INLINE int uabs_read_bit(struct AnsDecoder *ans) {
|
||||
int s;
|
||||
unsigned state = ans->state;
|
||||
if (state < l_base && ans->buf_offset > 0) {
|
||||
state = state * io_base + ans->buf[--ans->buf_offset];
|
||||
}
|
||||
s = (int)(state & 1);
|
||||
ans->state = state >> 1;
|
||||
return s;
|
||||
}
|
||||
|
||||
struct rans_sym {
|
||||
AnsP8 prob;
|
||||
AnsP8 cum_prob; // not-inclusive
|
||||
};
|
||||
|
||||
struct rans_dec_sym {
|
||||
uint8_t val;
|
||||
AnsP8 prob;
|
||||
AnsP8 cum_prob; // not-inclusive
|
||||
};
|
||||
|
||||
typedef struct rans_dec_sym rans_dec_lut[ans_p8_precision];
|
||||
|
||||
static INLINE void rans_build_dec_tab(const AnsP8 token_probs[],
|
||||
rans_dec_lut dec_tab) {
|
||||
int val = 0;
|
||||
int cum_prob = 0;
|
||||
int sym_end = token_probs[0];
|
||||
int i;
|
||||
for (i = 0; i < 256; ++i) {
|
||||
if (i == sym_end) {
|
||||
++val;
|
||||
cum_prob = sym_end;
|
||||
sym_end += token_probs[val];
|
||||
}
|
||||
dec_tab[i].val = val;
|
||||
dec_tab[i].prob = token_probs[val];
|
||||
dec_tab[i].cum_prob = cum_prob;
|
||||
}
|
||||
}
|
||||
|
||||
// rANS with normalization
|
||||
// sym->prob takes the place of l_s from the paper
|
||||
// ans_p8_precision is m
|
||||
static INLINE void rans_write(struct AnsCoder *ans,
|
||||
const struct rans_sym *const sym) {
|
||||
const AnsP8 p = sym->prob;
|
||||
if (ans->state >= l_base / ans_p8_precision * io_base * p) {
|
||||
ans->buf[ans->buf_offset++] = ans->state % io_base;
|
||||
ans->state /= io_base;
|
||||
}
|
||||
ans->state =
|
||||
(ans->state / p) * ans_p8_precision + ans->state % p + sym->cum_prob;
|
||||
}
|
||||
|
||||
static INLINE int rans_read(struct AnsDecoder *ans,
|
||||
const rans_dec_lut tab) {
|
||||
unsigned rem;
|
||||
unsigned quo;
|
||||
int val;
|
||||
if (ans->state < l_base && ans->buf_offset > 0) {
|
||||
ans->state = ans->state * io_base + ans->buf[--ans->buf_offset];
|
||||
}
|
||||
quo = ans->state / ans_p8_precision;
|
||||
rem = ans->state % ans_p8_precision;
|
||||
val = tab[rem].val;
|
||||
|
||||
ans->state = quo * tab[rem].prob + rem - tab[rem].cum_prob;
|
||||
return val;
|
||||
}
|
||||
|
||||
static INLINE int ans_read_init(struct AnsDecoder *const ans,
|
||||
const uint8_t *const buf,
|
||||
int offset) {
|
||||
if (offset < 3)
|
||||
return 1;
|
||||
ans->buf = buf;
|
||||
ans->buf_offset = offset - 3;
|
||||
ans->state = mem_get_le24(buf + offset - 3);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static INLINE int ans_read_end(struct AnsDecoder *const ans) {
|
||||
return ans->state == l_base;
|
||||
}
|
||||
#undef ANS_DIVREM
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif // __cplusplus
|
||||
#endif // VP10_COMMON_ANS_H_
|
||||
|
|
@ -0,0 +1,93 @@
|
|||
/*
|
||||
* Copyright (c) 2015 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 "vp10/common/divide.h"
|
||||
|
||||
/* Constants for divide by multiply for small divisors generated with:
|
||||
void init_fastdiv() {
|
||||
int i;
|
||||
for (i = 3; i < 256; ++i) {
|
||||
const int s = 31 ^ __builtin_clz(2 * i + 1);
|
||||
const unsigned long long base = (1ull << (sizeof(unsigned) * 8 + s)) - 1;
|
||||
fastdiv_tab[i].mult = (base / i + 1) & 0xFFFFFFFF;
|
||||
fastdiv_tab[i].shift = s;
|
||||
}
|
||||
for (i = 0; i < 8; ++i) {
|
||||
fastdiv_tab[1 << i].mult = 0;
|
||||
fastdiv_tab[1 << i].shift = i;
|
||||
}
|
||||
}
|
||||
*/
|
||||
const struct fastdiv_elem vp10_fastdiv_tab[256] = {
|
||||
{0, 0}, {0, 0}, {0, 1}, {1431655766, 2},
|
||||
{0, 2}, {2576980378, 3}, {1431655766, 3}, {613566757, 3},
|
||||
{0, 3}, {3340530120, 4}, {2576980378, 4}, {1952257862, 4},
|
||||
{1431655766, 4}, {991146300, 4}, {613566757, 4}, {286331154, 4},
|
||||
{0, 4}, {3789677026, 5}, {3340530120, 5}, {2938661835, 5},
|
||||
{2576980378, 5}, {2249744775, 5}, {1952257862, 5}, {1680639377, 5},
|
||||
{1431655766, 5}, {1202590843, 5}, {991146300, 5}, {795364315, 5},
|
||||
{613566757, 5}, {444306962, 5}, {286331154, 5}, {138547333, 5},
|
||||
{0, 5}, {4034666248, 6}, {3789677026, 6}, {3558687189, 6},
|
||||
{3340530120, 6}, {3134165325, 6}, {2938661835, 6}, {2753184165, 6},
|
||||
{2576980378, 6}, {2409371898, 6}, {2249744775, 6}, {2097542168, 6},
|
||||
{1952257862, 6}, {1813430637, 6}, {1680639377, 6}, {1553498810, 6},
|
||||
{1431655766, 6}, {1314785907, 6}, {1202590843, 6}, {1094795586, 6},
|
||||
{991146300, 6}, {891408307, 6}, {795364315, 6}, {702812831, 6},
|
||||
{613566757, 6}, {527452125, 6}, {444306962, 6}, {363980280, 6},
|
||||
{286331154, 6}, {211227900, 6}, {138547333, 6}, {68174085, 6},
|
||||
{0, 6}, {4162814457, 7}, {4034666248, 7}, {3910343360, 7},
|
||||
{3789677026, 7}, {3672508268, 7}, {3558687189, 7}, {3448072337, 7},
|
||||
{3340530120, 7}, {3235934265, 7}, {3134165325, 7}, {3035110223, 7},
|
||||
{2938661835, 7}, {2844718599, 7}, {2753184165, 7}, {2663967058, 7},
|
||||
{2576980378, 7}, {2492141518, 7}, {2409371898, 7}, {2328596727, 7},
|
||||
{2249744775, 7}, {2172748162, 7}, {2097542168, 7}, {2024065048, 7},
|
||||
{1952257862, 7}, {1882064321, 7}, {1813430637, 7}, {1746305385, 7},
|
||||
{1680639377, 7}, {1616385542, 7}, {1553498810, 7}, {1491936009, 7},
|
||||
{1431655766, 7}, {1372618415, 7}, {1314785907, 7}, {1258121734, 7},
|
||||
{1202590843, 7}, {1148159575, 7}, {1094795586, 7}, {1042467791, 7},
|
||||
{991146300, 7}, {940802361, 7}, {891408307, 7}, {842937507, 7},
|
||||
{795364315, 7}, {748664025, 7}, {702812831, 7}, {657787785, 7},
|
||||
{613566757, 7}, {570128403, 7}, {527452125, 7}, {485518043, 7},
|
||||
{444306962, 7}, {403800345, 7}, {363980280, 7}, {324829460, 7},
|
||||
{286331154, 7}, {248469183, 7}, {211227900, 7}, {174592167, 7},
|
||||
{138547333, 7}, {103079216, 7}, {68174085, 7}, {33818641, 7},
|
||||
{0, 7}, {4228378656, 8}, {4162814457, 8}, {4098251237, 8},
|
||||
{4034666248, 8}, {3972037425, 8}, {3910343360, 8}, {3849563281, 8},
|
||||
{3789677026, 8}, {3730665024, 8}, {3672508268, 8}, {3615188300, 8},
|
||||
{3558687189, 8}, {3502987511, 8}, {3448072337, 8}, {3393925206, 8},
|
||||
{3340530120, 8}, {3287871517, 8}, {3235934265, 8}, {3184703642, 8},
|
||||
{3134165325, 8}, {3084305374, 8}, {3035110223, 8}, {2986566663, 8},
|
||||
{2938661835, 8}, {2891383213, 8}, {2844718599, 8}, {2798656110, 8},
|
||||
{2753184165, 8}, {2708291480, 8}, {2663967058, 8}, {2620200175, 8},
|
||||
{2576980378, 8}, {2534297473, 8}, {2492141518, 8}, {2450502814, 8},
|
||||
{2409371898, 8}, {2368739540, 8}, {2328596727, 8}, {2288934667, 8},
|
||||
{2249744775, 8}, {2211018668, 8}, {2172748162, 8}, {2134925265, 8},
|
||||
{2097542168, 8}, {2060591247, 8}, {2024065048, 8}, {1987956292, 8},
|
||||
{1952257862, 8}, {1916962805, 8}, {1882064321, 8}, {1847555765, 8},
|
||||
{1813430637, 8}, {1779682582, 8}, {1746305385, 8}, {1713292966, 8},
|
||||
{1680639377, 8}, {1648338801, 8}, {1616385542, 8}, {1584774030, 8},
|
||||
{1553498810, 8}, {1522554545, 8}, {1491936009, 8}, {1461638086, 8},
|
||||
{1431655766, 8}, {1401984144, 8}, {1372618415, 8}, {1343553873, 8},
|
||||
{1314785907, 8}, {1286310003, 8}, {1258121734, 8}, {1230216764, 8},
|
||||
{1202590843, 8}, {1175239808, 8}, {1148159575, 8}, {1121346142, 8},
|
||||
{1094795586, 8}, {1068504060, 8}, {1042467791, 8}, {1016683080, 8},
|
||||
{991146300, 8}, {965853890, 8}, {940802361, 8}, {915988286, 8},
|
||||
{891408307, 8}, {867059126, 8}, {842937507, 8}, {819040276, 8},
|
||||
{795364315, 8}, {771906565, 8}, {748664025, 8}, {725633745, 8},
|
||||
{702812831, 8}, {680198441, 8}, {657787785, 8}, {635578121, 8},
|
||||
{613566757, 8}, {591751050, 8}, {570128403, 8}, {548696263, 8},
|
||||
{527452125, 8}, {506393524, 8}, {485518043, 8}, {464823301, 8},
|
||||
{444306962, 8}, {423966729, 8}, {403800345, 8}, {383805589, 8},
|
||||
{363980280, 8}, {344322273, 8}, {324829460, 8}, {305499766, 8},
|
||||
{286331154, 8}, {267321616, 8}, {248469183, 8}, {229771913, 8},
|
||||
{211227900, 8}, {192835267, 8}, {174592167, 8}, {156496785, 8},
|
||||
{138547333, 8}, {120742053, 8}, {103079216, 8}, {85557118, 8},
|
||||
{68174085, 8}, {50928466, 8}, {33818641, 8}, {16843010, 8},
|
||||
};
|
||||
|
|
@ -0,0 +1,40 @@
|
|||
/*
|
||||
* Copyright (c) 2015 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.
|
||||
*/
|
||||
|
||||
#ifndef VP10_COMMON_DIVIDE_H_
|
||||
#define VP10_COMMON_DIVIDE_H_
|
||||
// An implemntation of the divide by multiply alogrithm
|
||||
// https://gmplib.org/~tege/divcnst-pldi94.pdf
|
||||
|
||||
#include <limits.h>
|
||||
|
||||
#include "./vpx_config.h"
|
||||
#include "vpx/vpx_integer.h"
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif // __cplusplus
|
||||
|
||||
struct fastdiv_elem {
|
||||
unsigned mult;
|
||||
unsigned shift;
|
||||
};
|
||||
|
||||
extern const struct fastdiv_elem vp10_fastdiv_tab[256];
|
||||
|
||||
static INLINE unsigned fastdiv(unsigned x, int y) {
|
||||
unsigned t =
|
||||
((uint64_t)x * vp10_fastdiv_tab[y].mult) >> (sizeof(x) * CHAR_BIT);
|
||||
return (t + x) >> vp10_fastdiv_tab[y].shift;
|
||||
}
|
||||
#ifdef __cplusplus
|
||||
} // extern "C"
|
||||
#endif // __cplusplus
|
||||
#endif // VP10_COMMON_DIVIDE_H_
|
||||
|
|
@ -74,6 +74,9 @@ VP10_COMMON_SRCS-yes += common/vp10_fwd_txfm2d_cfg.h
|
|||
VP10_COMMON_SRCS-yes += common/vp10_inv_txfm2d.h
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VP10_COMMON_SRCS-yes += common/vp10_inv_txfm2d.c
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VP10_COMMON_SRCS-yes += common/vp10_inv_txfm2d_cfg.h
|
||||
VP10_COMMON_SRCS-$(CONFIG_ANS) += common/ans.h
|
||||
VP10_COMMON_SRCS-$(CONFIG_ANS) += common/divide.h
|
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VP10_COMMON_SRCS-$(CONFIG_ANS) += common/divide.c
|
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VP10_COMMON_SRCS-$(CONFIG_VP9_POSTPROC) += common/postproc.h
|
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VP10_COMMON_SRCS-$(CONFIG_VP9_POSTPROC) += common/postproc.c
|
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|
|
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Ссылка в новой задаче