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Diffstat (limited to 'vp9/encoder/vp9_segmentation.c')
-rw-r--r-- | vp9/encoder/vp9_segmentation.c | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/vp9/encoder/vp9_segmentation.c b/vp9/encoder/vp9_segmentation.c new file mode 100644 index 000000000..a9efff9f8 --- /dev/null +++ b/vp9/encoder/vp9_segmentation.c @@ -0,0 +1,332 @@ +/* + * Copyright (c) 2012 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 "limits.h" +#include "vpx_mem/vpx_mem.h" +#include "vp9_segmentation.h" +#include "vp9/common/vp9_pred_common.h" + +void vp9_update_gf_useage_maps(VP9_COMP *cpi, VP9_COMMON *cm, MACROBLOCK *x) { + int mb_row, mb_col; + + MODE_INFO *this_mb_mode_info = cm->mi; + + x->gf_active_ptr = (signed char *)cpi->gf_active_flags; + + if ((cm->frame_type == KEY_FRAME) || (cm->refresh_golden_frame)) { + // Reset Gf useage monitors + vpx_memset(cpi->gf_active_flags, 1, (cm->mb_rows * cm->mb_cols)); + cpi->gf_active_count = cm->mb_rows * cm->mb_cols; + } else { + // for each macroblock row in image + for (mb_row = 0; mb_row < cm->mb_rows; mb_row++) { + // for each macroblock col in image + for (mb_col = 0; mb_col < cm->mb_cols; mb_col++) { + + // If using golden then set GF active flag if not already set. + // If using last frame 0,0 mode then leave flag as it is + // else if using non 0,0 motion or intra modes then clear + // flag if it is currently set + if ((this_mb_mode_info->mbmi.ref_frame == GOLDEN_FRAME) || + (this_mb_mode_info->mbmi.ref_frame == ALTREF_FRAME)) { + if (*(x->gf_active_ptr) == 0) { + *(x->gf_active_ptr) = 1; + cpi->gf_active_count++; + } + } else if ((this_mb_mode_info->mbmi.mode != ZEROMV) && + *(x->gf_active_ptr)) { + *(x->gf_active_ptr) = 0; + cpi->gf_active_count--; + } + + x->gf_active_ptr++; // Step onto next entry + this_mb_mode_info++; // skip to next mb + + } + + // this is to account for the border + this_mb_mode_info++; + } + } +} + +void vp9_enable_segmentation(VP9_PTR ptr) { + VP9_COMP *cpi = (VP9_COMP *)(ptr); + + // Set the appropriate feature bit + cpi->mb.e_mbd.segmentation_enabled = 1; + cpi->mb.e_mbd.update_mb_segmentation_map = 1; + cpi->mb.e_mbd.update_mb_segmentation_data = 1; +} + +void vp9_disable_segmentation(VP9_PTR ptr) { + VP9_COMP *cpi = (VP9_COMP *)(ptr); + + // Clear the appropriate feature bit + cpi->mb.e_mbd.segmentation_enabled = 0; +} + +void vp9_set_segmentation_map(VP9_PTR ptr, + unsigned char *segmentation_map) { + VP9_COMP *cpi = (VP9_COMP *)(ptr); + + // Copy in the new segmentation map + vpx_memcpy(cpi->segmentation_map, segmentation_map, + (cpi->common.mb_rows * cpi->common.mb_cols)); + + // Signal that the map should be updated. + cpi->mb.e_mbd.update_mb_segmentation_map = 1; + cpi->mb.e_mbd.update_mb_segmentation_data = 1; +} + +void vp9_set_segment_data(VP9_PTR ptr, + signed char *feature_data, + unsigned char abs_delta) { + VP9_COMP *cpi = (VP9_COMP *)(ptr); + + cpi->mb.e_mbd.mb_segment_abs_delta = abs_delta; + + vpx_memcpy(cpi->mb.e_mbd.segment_feature_data, feature_data, + sizeof(cpi->mb.e_mbd.segment_feature_data)); + + // TBD ?? Set the feature mask + // vpx_memcpy(cpi->mb.e_mbd.segment_feature_mask, 0, + // sizeof(cpi->mb.e_mbd.segment_feature_mask)); +} + +// Based on set of segment counts calculate a probability tree +static void calc_segtree_probs(MACROBLOCKD *xd, + int *segcounts, + vp9_prob *segment_tree_probs) { + int count1, count2; + int tot_count; + int i; + + // Blank the strtucture to start with + vpx_memset(segment_tree_probs, 0, + MB_FEATURE_TREE_PROBS * sizeof(*segment_tree_probs)); + + // Total count for all segments + count1 = segcounts[0] + segcounts[1]; + count2 = segcounts[2] + segcounts[3]; + tot_count = count1 + count2; + + // Work out probabilities of each segment + if (tot_count) + segment_tree_probs[0] = (count1 * 255) / tot_count; + if (count1 > 0) + segment_tree_probs[1] = (segcounts[0] * 255) / count1; + if (count2 > 0) + segment_tree_probs[2] = (segcounts[2] * 255) / count2; + + // Clamp probabilities to minimum allowed value + for (i = 0; i < MB_FEATURE_TREE_PROBS; i++) { + if (segment_tree_probs[i] == 0) + segment_tree_probs[i] = 1; + } +} + +// Based on set of segment counts and probabilities calculate a cost estimate +static int cost_segmap(MACROBLOCKD *xd, + int *segcounts, + vp9_prob *probs) { + int cost; + int count1, count2; + + // Cost the top node of the tree + count1 = segcounts[0] + segcounts[1]; + count2 = segcounts[2] + segcounts[3]; + cost = count1 * vp9_cost_zero(probs[0]) + + count2 * vp9_cost_one(probs[0]); + + // Now add the cost of each individual segment branch + if (count1 > 0) + cost += segcounts[0] * vp9_cost_zero(probs[1]) + + segcounts[1] * vp9_cost_one(probs[1]); + + if (count2 > 0) + cost += segcounts[2] * vp9_cost_zero(probs[2]) + + segcounts[3] * vp9_cost_one(probs[2]); + + return cost; + +} + +void vp9_choose_segmap_coding_method(VP9_COMP *cpi) { + VP9_COMMON *const cm = &cpi->common; + MACROBLOCKD *const xd = &cpi->mb.e_mbd; + + const int mis = cm->mode_info_stride; + int i; + int tot_count; + int no_pred_cost; + int t_pred_cost = INT_MAX; + int pred_context; + + int mb_row, mb_col; + int segmap_index = 0; + unsigned char segment_id; + + int temporal_predictor_count[PREDICTION_PROBS][2]; + int no_pred_segcounts[MAX_MB_SEGMENTS]; + int t_unpred_seg_counts[MAX_MB_SEGMENTS]; + + vp9_prob no_pred_tree[MB_FEATURE_TREE_PROBS]; + vp9_prob t_pred_tree[MB_FEATURE_TREE_PROBS]; + vp9_prob t_nopred_prob[PREDICTION_PROBS]; + + // Set default state for the segment tree probabilities and the + // temporal coding probabilities + vpx_memset(xd->mb_segment_tree_probs, 255, + sizeof(xd->mb_segment_tree_probs)); + vpx_memset(cm->segment_pred_probs, 255, + sizeof(cm->segment_pred_probs)); + + vpx_memset(no_pred_segcounts, 0, sizeof(no_pred_segcounts)); + vpx_memset(t_unpred_seg_counts, 0, sizeof(t_unpred_seg_counts)); + vpx_memset(temporal_predictor_count, 0, sizeof(temporal_predictor_count)); + + // First of all generate stats regarding how well the last segment map + // predicts this one + + // Initialize macroblock decoder mode info context for the first mb + // in the frame + xd->mode_info_context = cm->mi; + + for (mb_row = 0; mb_row < cm->mb_rows; mb_row += 2) { + for (mb_col = 0; mb_col < cm->mb_cols; mb_col += 2) { + for (i = 0; i < 4; i++) { + static const int dx[4] = { +1, -1, +1, +1 }; + static const int dy[4] = { 0, +1, 0, -1 }; + int x_idx = i & 1, y_idx = i >> 1; + + if (mb_col + x_idx >= cm->mb_cols || + mb_row + y_idx >= cm->mb_rows) { + goto end; + } + + xd->mb_to_top_edge = -((mb_row * 16) << 3); + xd->mb_to_left_edge = -((mb_col * 16) << 3); + + segmap_index = (mb_row + y_idx) * cm->mb_cols + mb_col + x_idx; + segment_id = xd->mode_info_context->mbmi.segment_id; +#if CONFIG_SUPERBLOCKS + if (xd->mode_info_context->mbmi.encoded_as_sb) { + if (mb_col + 1 < cm->mb_cols) + segment_id = segment_id && + xd->mode_info_context[1].mbmi.segment_id; + if (mb_row + 1 < cm->mb_rows) { + segment_id = segment_id && + xd->mode_info_context[mis].mbmi.segment_id; + if (mb_col + 1 < cm->mb_cols) + segment_id = segment_id && + xd->mode_info_context[mis + 1].mbmi.segment_id; + } + xd->mb_to_bottom_edge = ((cm->mb_rows - 2 - mb_row) * 16) << 3; + xd->mb_to_right_edge = ((cm->mb_cols - 2 - mb_col) * 16) << 3; + } else { +#endif + xd->mb_to_bottom_edge = ((cm->mb_rows - 1 - mb_row) * 16) << 3; + xd->mb_to_right_edge = ((cm->mb_cols - 1 - mb_col) * 16) << 3; +#if CONFIG_SUPERBLOCKS + } +#endif + + // Count the number of hits on each segment with no prediction + no_pred_segcounts[segment_id]++; + + // Temporal prediction not allowed on key frames + if (cm->frame_type != KEY_FRAME) { + // Test to see if the segment id matches the predicted value. + int seg_predicted = + (segment_id == vp9_get_pred_mb_segid(cm, xd, segmap_index)); + + // Get the segment id prediction context + pred_context = + vp9_get_pred_context(cm, xd, PRED_SEG_ID); + + // Store the prediction status for this mb and update counts + // as appropriate + vp9_set_pred_flag(xd, PRED_SEG_ID, seg_predicted); + temporal_predictor_count[pred_context][seg_predicted]++; + + if (!seg_predicted) + // Update the "unpredicted" segment count + t_unpred_seg_counts[segment_id]++; + } + +#if CONFIG_SUPERBLOCKS + if (xd->mode_info_context->mbmi.encoded_as_sb) { + assert(!i); + xd->mode_info_context += 2; + break; + } +#endif + end: + xd->mode_info_context += dx[i] + dy[i] * cm->mode_info_stride; + } + } + + // this is to account for the border in mode_info_context + xd->mode_info_context -= mb_col; + xd->mode_info_context += cm->mode_info_stride * 2; + } + + // Work out probability tree for coding segments without prediction + // and the cost. + calc_segtree_probs(xd, no_pred_segcounts, no_pred_tree); + no_pred_cost = cost_segmap(xd, no_pred_segcounts, no_pred_tree); + + // Key frames cannot use temporal prediction + if (cm->frame_type != KEY_FRAME) { + // Work out probability tree for coding those segments not + // predicted using the temporal method and the cost. + calc_segtree_probs(xd, t_unpred_seg_counts, t_pred_tree); + t_pred_cost = cost_segmap(xd, t_unpred_seg_counts, t_pred_tree); + + // Add in the cost of the signalling for each prediction context + for (i = 0; i < PREDICTION_PROBS; i++) { + tot_count = temporal_predictor_count[i][0] + + temporal_predictor_count[i][1]; + + // Work out the context probabilities for the segment + // prediction flag + if (tot_count) { + t_nopred_prob[i] = (temporal_predictor_count[i][0] * 255) / + tot_count; + + // Clamp to minimum allowed value + if (t_nopred_prob[i] < 1) + t_nopred_prob[i] = 1; + } else + t_nopred_prob[i] = 1; + + // Add in the predictor signaling cost + t_pred_cost += (temporal_predictor_count[i][0] * + vp9_cost_zero(t_nopred_prob[i])) + + (temporal_predictor_count[i][1] * + vp9_cost_one(t_nopred_prob[i])); + } + } + + // Now choose which coding method to use. + if (t_pred_cost < no_pred_cost) { + cm->temporal_update = 1; + vpx_memcpy(xd->mb_segment_tree_probs, + t_pred_tree, sizeof(t_pred_tree)); + vpx_memcpy(&cm->segment_pred_probs, + t_nopred_prob, sizeof(t_nopred_prob)); + } else { + cm->temporal_update = 0; + vpx_memcpy(xd->mb_segment_tree_probs, + no_pred_tree, sizeof(no_pred_tree)); + } +} |