summaryrefslogtreecommitdiffstats
path: root/media/libvpx/vp8/encoder/encodemv.c
diff options
context:
space:
mode:
Diffstat (limited to 'media/libvpx/vp8/encoder/encodemv.c')
-rw-r--r--media/libvpx/vp8/encoder/encodemv.c380
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
+}