diff options
Diffstat (limited to 'third_party/aom/av1/decoder/pvq_decoder.c')
| -rw-r--r-- | third_party/aom/av1/decoder/pvq_decoder.c | 378 |
1 files changed, 378 insertions, 0 deletions
diff --git a/third_party/aom/av1/decoder/pvq_decoder.c b/third_party/aom/av1/decoder/pvq_decoder.c new file mode 100644 index 000000000..d9a8e8056 --- /dev/null +++ b/third_party/aom/av1/decoder/pvq_decoder.c @@ -0,0 +1,378 @@ +/* + * Copyright (c) 2001-2016, 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. + */ + +/* clang-format off */ + +#ifdef HAVE_CONFIG_H +# include "config.h" +#endif + +#include <stdio.h> +#include <stdlib.h> +#include "./aom_config.h" +#include "aom_dsp/bitreader.h" +#include "aom_dsp/entcode.h" +#include "aom_dsp/entdec.h" +#include "av1/common/odintrin.h" +#include "av1/common/partition.h" +#include "av1/common/pvq_state.h" +#include "av1/decoder/decint.h" +#include "av1/decoder/pvq_decoder.h" +#include "aom_ports/system_state.h" + +int aom_read_symbol_pvq_(aom_reader *r, aom_cdf_prob *cdf, int nsymbs + ACCT_STR_PARAM) { + if (cdf[0] == 0) + aom_cdf_init_q15_1D(cdf, nsymbs, CDF_SIZE(nsymbs)); + return aom_read_symbol(r, cdf, nsymbs, ACCT_STR_NAME); +} + +static void aom_decode_pvq_codeword(aom_reader *r, od_pvq_codeword_ctx *ctx, + od_coeff *y, int n, int k) { + int i; + aom_decode_band_pvq_splits(r, ctx, y, n, k, 0); + for (i = 0; i < n; i++) { + if (y[i] && aom_read_bit(r, "pvq:sign")) y[i] = -y[i]; + } +} + +/** Inverse of neg_interleave; decodes the interleaved gain. + * + * @param [in] x quantized/interleaved gain to decode + * @param [in] ref quantized gain of the reference + * @return original quantized gain value + */ +static int neg_deinterleave(int x, int ref) { + if (x < 2*ref-1) { + if (x & 1) return ref - 1 - (x >> 1); + else return ref + (x >> 1); + } + else return x+1; +} + +/** Synthesizes one parition of coefficient values from a PVQ-encoded + * vector. + * + * @param [out] xcoeff output coefficient partition (x in math doc) + * @param [in] ypulse PVQ-encoded values (y in math doc); in the noref + * case, this vector has n entries, in the + * reference case it contains n-1 entries + * (the m-th entry is not included) + * @param [in] ref reference vector (prediction) + * @param [in] n number of elements in this partition + * @param [in] gr gain of the reference vector (prediction) + * @param [in] noref indicates presence or lack of prediction + * @param [in] g decoded quantized vector gain + * @param [in] theta decoded theta (prediction error) + * @param [in] qm QM with magnitude compensation + * @param [in] qm_inv Inverse of QM with magnitude compensation + */ +static void pvq_synthesis(od_coeff *xcoeff, od_coeff *ypulse, od_val16 *r16, + int n, od_val32 gr, int noref, od_val32 g, od_val32 theta, const int16_t *qm_inv, + int shift) { + int s; + int m; + /* Sign of the Householder reflection vector */ + s = 0; + /* Direction of the Householder reflection vector */ + m = noref ? 0 : od_compute_householder(r16, n, gr, &s, shift); + od_pvq_synthesis_partial(xcoeff, ypulse, r16, n, noref, g, theta, m, s, + qm_inv); +} + +typedef struct { + od_coeff *ref; + int nb_coeffs; + int allow_flip; +} cfl_ctx; + +/** Decodes a single vector of integers (eg, a partition within a + * coefficient block) encoded using PVQ + * + * @param [in,out] ec range encoder + * @param [in] q0 scale/quantizer + * @param [in] n number of coefficients in partition + * @param [in,out] model entropy decoder state + * @param [in,out] adapt adaptation context + * @param [in,out] exg ExQ16 expectation of decoded gain value + * @param [in,out] ext ExQ16 expectation of decoded theta value + * @param [in] ref 'reference' (prediction) vector + * @param [out] out decoded partition + * @param [out] noref boolean indicating absence of reference + * @param [in] beta per-band activity masking beta param + * @param [in] is_keyframe whether we're encoding a keyframe + * @param [in] pli plane index + * @param [in] cdf_ctx selects which cdf context to use + * @param [in,out] skip_rest whether to skip further bands in each direction + * @param [in] band index of the band being decoded + * @param [in] band index of the band being decoded + * @param [out] skip skip flag with range [0,1] + * @param [in] qm QM with magnitude compensation + * @param [in] qm_inv Inverse of QM with magnitude compensation + */ +static void pvq_decode_partition(aom_reader *r, + int q0, + int n, + generic_encoder model[3], + od_adapt_ctx *adapt, + int *exg, + int *ext, + od_coeff *ref, + od_coeff *out, + int *noref, + od_val16 beta, + int is_keyframe, + int pli, + int cdf_ctx, + cfl_ctx *cfl, + int has_skip, + int *skip_rest, + int band, + int *skip, + const int16_t *qm, + const int16_t *qm_inv) { + int k; + od_val32 qcg; + int itheta; + od_val32 theta; + od_val32 gr; + od_val32 gain_offset; + od_coeff y[MAXN]; + int qg; + int id; + int i; + od_val16 ref16[MAXN]; + int rshift; + theta = 0; + gr = 0; + gain_offset = 0; + /* Skip is per-direction. For band=0, we can use any of the flags. */ + if (skip_rest[(band + 2) % 3]) { + qg = 0; + if (is_keyframe) { + itheta = -1; + *noref = 1; + } + else { + itheta = 0; + *noref = 0; + } + } + else { + /* Jointly decode gain, itheta and noref for small values. Then we handle + larger gain. */ + id = aom_read_symbol_pvq(r, &adapt->pvq.pvq_gaintheta_cdf[cdf_ctx][0], + 8 + 7*has_skip, "pvq:gaintheta"); + if (!is_keyframe && id >= 10) id++; + if (is_keyframe && id >= 8) id++; + if (id >= 8) { + id -= 8; + skip_rest[0] = skip_rest[1] = skip_rest[2] = 1; + } + qg = id & 1; + itheta = (id >> 1) - 1; + *noref = (itheta == -1); + } + /* The CfL flip bit is only decoded on the first band that has noref=0. */ + if (cfl->allow_flip && !*noref) { + int flip; + flip = aom_read_bit(r, "cfl:flip"); + if (flip) { + for (i = 0; i < cfl->nb_coeffs; i++) cfl->ref[i] = -cfl->ref[i]; + } + cfl->allow_flip = 0; + } + if (qg > 0) { + int tmp; + tmp = *exg; + qg = 1 + generic_decode(r, &model[!*noref], &tmp, 2, "pvq:gain"); + OD_IIR_DIADIC(*exg, qg << 16, 2); + } + *skip = 0; +#if defined(OD_FLOAT_PVQ) + rshift = 0; +#else + /* Shift needed to make the reference fit in 15 bits, so that the Householder + vector can fit in 16 bits. */ + rshift = OD_MAXI(0, od_vector_log_mag(ref, n) - 14); +#endif + for (i = 0; i < n; i++) { +#if defined(OD_FLOAT_PVQ) + ref16[i] = ref[i]*(double)qm[i]*OD_QM_SCALE_1; +#else + ref16[i] = OD_SHR_ROUND(ref[i]*qm[i], OD_QM_SHIFT + rshift); +#endif + } + if(!*noref){ + /* we have a reference; compute its gain */ + od_val32 cgr; + int icgr; + int cfl_enabled; + cfl_enabled = pli != 0 && is_keyframe && !OD_DISABLE_CFL; + cgr = od_pvq_compute_gain(ref16, n, q0, &gr, beta, rshift); + if (cfl_enabled) cgr = OD_CGAIN_SCALE; +#if defined(OD_FLOAT_PVQ) + icgr = (int)floor(.5 + cgr); +#else + icgr = OD_SHR_ROUND(cgr, OD_CGAIN_SHIFT); +#endif + /* quantized gain is interleave encoded when there's a reference; + deinterleave it now */ + if (is_keyframe) qg = neg_deinterleave(qg, icgr); + else { + qg = neg_deinterleave(qg, icgr + 1) - 1; + if (qg == 0) *skip = (icgr ? OD_PVQ_SKIP_ZERO : OD_PVQ_SKIP_COPY); + } + if (qg == icgr && itheta == 0 && !cfl_enabled) *skip = OD_PVQ_SKIP_COPY; + gain_offset = cgr - OD_SHL(icgr, OD_CGAIN_SHIFT); + qcg = OD_SHL(qg, OD_CGAIN_SHIFT) + gain_offset; + /* read and decode first-stage PVQ error theta */ + if (itheta > 1) { + int tmp; + tmp = *ext; + itheta = 2 + generic_decode(r, &model[2], &tmp, 2, "pvq:theta"); + OD_IIR_DIADIC(*ext, itheta << 16, 2); + } + theta = od_pvq_compute_theta(itheta, od_pvq_compute_max_theta(qcg, beta)); + } + else{ + itheta = 0; + if (!is_keyframe) qg++; + qcg = OD_SHL(qg, OD_CGAIN_SHIFT); + if (qg == 0) *skip = OD_PVQ_SKIP_ZERO; + } + + k = od_pvq_compute_k(qcg, itheta, *noref, n, beta); + if (k != 0) { + /* when noref==0, y is actually size n-1 */ + aom_decode_pvq_codeword(r, &adapt->pvq.pvq_codeword_ctx, y, + n - !*noref, k); + } + else { + OD_CLEAR(y, n); + } + if (*skip) { + if (*skip == OD_PVQ_SKIP_COPY) OD_COPY(out, ref, n); + else OD_CLEAR(out, n); + } + else { + od_val32 g; + g = od_gain_expand(qcg, q0, beta); + pvq_synthesis(out, y, ref16, n, gr, *noref, g, theta, qm_inv, rshift); + } + /* If OD_PVQ_SKIP_ZERO or OD_PVQ_SKIP_COPY, set skip to 1 for visualization */ + if (*skip) *skip = 1; +} + +/** Decodes a coefficient block (except for DC) encoded using PVQ + * + * @param [in,out] dec daala decoder context + * @param [in] ref 'reference' (prediction) vector + * @param [out] out decoded partition + * @param [in] q0 quantizer + * @param [in] pli plane index + * @param [in] bs log of the block size minus two + * @param [in] beta per-band activity masking beta param + * @param [in] is_keyframe whether we're encoding a keyframe + * @param [out] flags bitmask of the per band skip and noref flags + * @param [in] ac_dc_coded skip flag for the block (range 0-3) + * @param [in] qm QM with magnitude compensation + * @param [in] qm_inv Inverse of QM with magnitude compensation + */ +void od_pvq_decode(daala_dec_ctx *dec, + od_coeff *ref, + od_coeff *out, + int q0, + int pli, + int bs, + const od_val16 *beta, + int is_keyframe, + unsigned int *flags, + PVQ_SKIP_TYPE ac_dc_coded, + const int16_t *qm, + const int16_t *qm_inv){ + + int noref[PVQ_MAX_PARTITIONS]; + int skip[PVQ_MAX_PARTITIONS]; + int *exg; + int *ext; + int nb_bands; + int i; + const int *off; + int size[PVQ_MAX_PARTITIONS]; + generic_encoder *model; + int skip_rest[3] = {0}; + cfl_ctx cfl; + const unsigned char *pvq_qm; + int use_masking; + + aom_clear_system_state(); + + /*Default to skip=1 and noref=0 for all bands.*/ + for (i = 0; i < PVQ_MAX_PARTITIONS; i++) { + noref[i] = 0; + skip[i] = 1; + } + + use_masking = dec->use_activity_masking; + + if (use_masking) + pvq_qm = &dec->state.pvq_qm_q4[pli][0]; + else + pvq_qm = 0; + + exg = &dec->state.adapt->pvq.pvq_exg[pli][bs][0]; + ext = dec->state.adapt->pvq.pvq_ext + bs*PVQ_MAX_PARTITIONS; + model = dec->state.adapt->pvq.pvq_param_model; + nb_bands = OD_BAND_OFFSETS[bs][0]; + off = &OD_BAND_OFFSETS[bs][1]; + out[0] = ac_dc_coded & DC_CODED; + if (ac_dc_coded < AC_CODED) { + if (is_keyframe) for (i = 1; i < 1 << (2*bs + 4); i++) out[i] = 0; + else for (i = 1; i < 1 << (2*bs + 4); i++) out[i] = ref[i]; + } + else { + for (i = 0; i < nb_bands; i++) size[i] = off[i+1] - off[i]; + cfl.ref = ref; + cfl.nb_coeffs = off[nb_bands]; + cfl.allow_flip = pli != 0 && is_keyframe; + for (i = 0; i < nb_bands; i++) { + int q; + + if (use_masking) + q = OD_MAXI(1, q0 * pvq_qm[od_qm_get_index(bs, i + 1)] >> 4); + else + q = OD_MAXI(1, q0); + + pvq_decode_partition(dec->r, q, size[i], + model, dec->state.adapt, exg + i, ext + i, ref + off[i], out + off[i], + &noref[i], beta[i], is_keyframe, pli, + (pli != 0)*OD_TXSIZES*PVQ_MAX_PARTITIONS + bs*PVQ_MAX_PARTITIONS + i, + &cfl, i == 0 && (i < nb_bands - 1), skip_rest, i, &skip[i], + qm + off[i], qm_inv + off[i]); + if (i == 0 && !skip_rest[0] && bs > 0) { + int skip_dir; + int j; + skip_dir = aom_read_symbol(dec->r, + &dec->state.adapt->pvq.pvq_skip_dir_cdf[(pli != 0) + 2*(bs - 1)][0], 7, + "pvq:skiprest"); + for (j = 0; j < 3; j++) skip_rest[j] = !!(skip_dir & (1 << j)); + } + } + } + *flags = 0; + for (i = nb_bands - 1; i >= 0; i--) { + *flags <<= 1; + *flags |= noref[i]&1; + *flags <<= 1; + *flags |= skip[i]&1; + } +} |