diff options
Diffstat (limited to 'media/libvpx/vp8/encoder/encodemv.c')
| -rw-r--r-- | media/libvpx/vp8/encoder/encodemv.c | 380 |
1 files changed, 380 insertions, 0 deletions
diff --git a/media/libvpx/vp8/encoder/encodemv.c b/media/libvpx/vp8/encoder/encodemv.c new file mode 100644 index 000000000..2a74ff4ae --- /dev/null +++ b/media/libvpx/vp8/encoder/encodemv.c @@ -0,0 +1,380 @@ +/* + * Copyright (c) 2010 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 "vp8/common/common.h" +#include "encodemv.h" +#include "vp8/common/entropymode.h" +#include "vp8/common/systemdependent.h" + +#include <math.h> + +#ifdef VP8_ENTROPY_STATS +extern unsigned int active_section; +#endif + +static void encode_mvcomponent( + vp8_writer *const w, + const int v, + const struct mv_context *mvc +) +{ + const vp8_prob *p = mvc->prob; + const int x = v < 0 ? -v : v; + + if (x < mvnum_short) /* Small */ + { + vp8_write(w, 0, p [mvpis_short]); + vp8_treed_write(w, vp8_small_mvtree, p + MVPshort, x, 3); + + if (!x) + return; /* no sign bit */ + } + else /* Large */ + { + int i = 0; + + vp8_write(w, 1, p [mvpis_short]); + + do + vp8_write(w, (x >> i) & 1, p [MVPbits + i]); + + while (++i < 3); + + i = mvlong_width - 1; /* Skip bit 3, which is sometimes implicit */ + + do + vp8_write(w, (x >> i) & 1, p [MVPbits + i]); + + while (--i > 3); + + if (x & 0xFFF0) + vp8_write(w, (x >> 3) & 1, p [MVPbits + 3]); + } + + vp8_write(w, v < 0, p [MVPsign]); +} +#if 0 +static int max_mv_r = 0; +static int max_mv_c = 0; +#endif +void vp8_encode_motion_vector(vp8_writer *w, const MV *mv, const MV_CONTEXT *mvc) +{ + +#if 0 + { + if (abs(mv->row >> 1) > max_mv_r) + { + FILE *f = fopen("maxmv.stt", "a"); + max_mv_r = abs(mv->row >> 1); + fprintf(f, "New Mv Row Max %6d\n", (mv->row >> 1)); + + if ((abs(mv->row) / 2) != max_mv_r) + fprintf(f, "MV Row conversion error %6d\n", abs(mv->row) / 2); + + fclose(f); + } + + if (abs(mv->col >> 1) > max_mv_c) + { + FILE *f = fopen("maxmv.stt", "a"); + fprintf(f, "New Mv Col Max %6d\n", (mv->col >> 1)); + max_mv_c = abs(mv->col >> 1); + fclose(f); + } + } +#endif + + encode_mvcomponent(w, mv->row >> 1, &mvc[0]); + encode_mvcomponent(w, mv->col >> 1, &mvc[1]); +} + + +static unsigned int cost_mvcomponent(const int v, const struct mv_context *mvc) +{ + const vp8_prob *p = mvc->prob; + const int x = v; + unsigned int cost; + + if (x < mvnum_short) + { + cost = vp8_cost_zero(p [mvpis_short]) + + vp8_treed_cost(vp8_small_mvtree, p + MVPshort, x, 3); + + if (!x) + return cost; + } + else + { + int i = 0; + cost = vp8_cost_one(p [mvpis_short]); + + do + cost += vp8_cost_bit(p [MVPbits + i], (x >> i) & 1); + + while (++i < 3); + + i = mvlong_width - 1; /* Skip bit 3, which is sometimes implicit */ + + do + cost += vp8_cost_bit(p [MVPbits + i], (x >> i) & 1); + + while (--i > 3); + + if (x & 0xFFF0) + cost += vp8_cost_bit(p [MVPbits + 3], (x >> 3) & 1); + } + + return cost; /* + vp8_cost_bit( p [MVPsign], v < 0); */ +} + +void vp8_build_component_cost_table(int *mvcost[2], const MV_CONTEXT *mvc, int mvc_flag[2]) +{ + int i = 1; + unsigned int cost0 = 0; + unsigned int cost1 = 0; + + vp8_clear_system_state(); + + i = 1; + + if (mvc_flag[0]) + { + mvcost [0] [0] = cost_mvcomponent(0, &mvc[0]); + + do + { + cost0 = cost_mvcomponent(i, &mvc[0]); + + mvcost [0] [i] = cost0 + vp8_cost_zero(mvc[0].prob[MVPsign]); + mvcost [0] [-i] = cost0 + vp8_cost_one(mvc[0].prob[MVPsign]); + } + while (++i <= mv_max); + } + + i = 1; + + if (mvc_flag[1]) + { + mvcost [1] [0] = cost_mvcomponent(0, &mvc[1]); + + do + { + cost1 = cost_mvcomponent(i, &mvc[1]); + + mvcost [1] [i] = cost1 + vp8_cost_zero(mvc[1].prob[MVPsign]); + mvcost [1] [-i] = cost1 + vp8_cost_one(mvc[1].prob[MVPsign]); + } + while (++i <= mv_max); + } +} + + +/* Motion vector probability table update depends on benefit. + * Small correction allows for the fact that an update to an MV probability + * may have benefit in subsequent frames as well as the current one. + */ +#define MV_PROB_UPDATE_CORRECTION -1 + + +static void calc_prob(vp8_prob *p, const unsigned int ct[2]) +{ + const unsigned int tot = ct[0] + ct[1]; + + if (tot) + { + const vp8_prob x = ((ct[0] * 255) / tot) & -2; + *p = x ? x : 1; + } +} + +static void update( + vp8_writer *const w, + const unsigned int ct[2], + vp8_prob *const cur_p, + const vp8_prob new_p, + const vp8_prob update_p, + int *updated +) +{ + const int cur_b = vp8_cost_branch(ct, *cur_p); + const int new_b = vp8_cost_branch(ct, new_p); + const int cost = 7 + MV_PROB_UPDATE_CORRECTION + ((vp8_cost_one(update_p) - vp8_cost_zero(update_p) + 128) >> 8); + + if (cur_b - new_b > cost) + { + *cur_p = new_p; + vp8_write(w, 1, update_p); + vp8_write_literal(w, new_p >> 1, 7); + *updated = 1; + + } + else + vp8_write(w, 0, update_p); +} + +static void write_component_probs( + vp8_writer *const w, + struct mv_context *cur_mvc, + const struct mv_context *default_mvc_, + const struct mv_context *update_mvc, + const unsigned int events [MVvals], + unsigned int rc, + int *updated +) +{ + vp8_prob *Pcur = cur_mvc->prob; + const vp8_prob *default_mvc = default_mvc_->prob; + const vp8_prob *Pupdate = update_mvc->prob; + unsigned int is_short_ct[2], sign_ct[2]; + + unsigned int bit_ct [mvlong_width] [2]; + + unsigned int short_ct [mvnum_short]; + unsigned int short_bct [mvnum_short-1] [2]; + + vp8_prob Pnew [MVPcount]; + + (void) rc; + vp8_copy_array(Pnew, default_mvc, MVPcount); + + vp8_zero(is_short_ct) + vp8_zero(sign_ct) + vp8_zero(bit_ct) + vp8_zero(short_ct) + vp8_zero(short_bct) + + + /* j=0 */ + { + const int c = events [mv_max]; + + is_short_ct [0] += c; /* Short vector */ + short_ct [0] += c; /* Magnitude distribution */ + } + + /* j: 1 ~ mv_max (1023) */ + { + int j = 1; + + do + { + const int c1 = events [mv_max + j]; /* positive */ + const int c2 = events [mv_max - j]; /* negative */ + const int c = c1 + c2; + int a = j; + + sign_ct [0] += c1; + sign_ct [1] += c2; + + if (a < mvnum_short) + { + is_short_ct [0] += c; /* Short vector */ + short_ct [a] += c; /* Magnitude distribution */ + } + else + { + int k = mvlong_width - 1; + is_short_ct [1] += c; /* Long vector */ + + /* bit 3 not always encoded. */ + do + bit_ct [k] [(a >> k) & 1] += c; + + while (--k >= 0); + } + } + while (++j <= mv_max); + } + + calc_prob(Pnew + mvpis_short, is_short_ct); + + calc_prob(Pnew + MVPsign, sign_ct); + + { + vp8_prob p [mvnum_short - 1]; /* actually only need branch ct */ + int j = 0; + + vp8_tree_probs_from_distribution( + 8, vp8_small_mvencodings, vp8_small_mvtree, + p, short_bct, short_ct, + 256, 1 + ); + + do + calc_prob(Pnew + MVPshort + j, short_bct[j]); + + while (++j < mvnum_short - 1); + } + + { + int j = 0; + + do + calc_prob(Pnew + MVPbits + j, bit_ct[j]); + + while (++j < mvlong_width); + } + + update(w, is_short_ct, Pcur + mvpis_short, Pnew[mvpis_short], *Pupdate++, updated); + + update(w, sign_ct, Pcur + MVPsign, Pnew[MVPsign], *Pupdate++, updated); + + { + const vp8_prob *const new_p = Pnew + MVPshort; + vp8_prob *const cur_p = Pcur + MVPshort; + + int j = 0; + + do + + update(w, short_bct[j], cur_p + j, new_p[j], *Pupdate++, updated); + + while (++j < mvnum_short - 1); + } + + { + const vp8_prob *const new_p = Pnew + MVPbits; + vp8_prob *const cur_p = Pcur + MVPbits; + + int j = 0; + + do + + update(w, bit_ct[j], cur_p + j, new_p[j], *Pupdate++, updated); + + while (++j < mvlong_width); + } +} + +void vp8_write_mvprobs(VP8_COMP *cpi) +{ + vp8_writer *const w = cpi->bc; + MV_CONTEXT *mvc = cpi->common.fc.mvc; + int flags[2] = {0, 0}; +#ifdef VP8_ENTROPY_STATS + active_section = 4; +#endif + write_component_probs( + w, &mvc[0], &vp8_default_mv_context[0], &vp8_mv_update_probs[0], + cpi->mb.MVcount[0], 0, &flags[0] + ); + write_component_probs( + w, &mvc[1], &vp8_default_mv_context[1], &vp8_mv_update_probs[1], + cpi->mb.MVcount[1], 1, &flags[1] + ); + + if (flags[0] || flags[1]) + vp8_build_component_cost_table(cpi->mb.mvcost, (const MV_CONTEXT *) cpi->common.fc.mvc, flags); + +#ifdef VP8_ENTROPY_STATS + active_section = 5; +#endif +} |