diff options
Diffstat (limited to 'media/libvpx/vp9/encoder/vp9_aq_complexity.c')
| -rw-r--r-- | media/libvpx/vp9/encoder/vp9_aq_complexity.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/media/libvpx/vp9/encoder/vp9_aq_complexity.c b/media/libvpx/vp9/encoder/vp9_aq_complexity.c new file mode 100644 index 000000000..bea7653d2 --- /dev/null +++ b/media/libvpx/vp9/encoder/vp9_aq_complexity.c @@ -0,0 +1,163 @@ +/* + * Copyright (c) 2014 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 <math.h> + +#include "vp9/encoder/vp9_aq_complexity.h" +#include "vp9/encoder/vp9_aq_variance.h" +#include "vp9/encoder/vp9_encodeframe.h" +#include "vp9/common/vp9_seg_common.h" +#include "vp9/encoder/vp9_segmentation.h" + +#define AQ_C_SEGMENTS 5 +#define DEFAULT_AQ2_SEG 3 // Neutral Q segment +#define AQ_C_STRENGTHS 3 +static const double aq_c_q_adj_factor[AQ_C_STRENGTHS][AQ_C_SEGMENTS] = + { {1.75, 1.25, 1.05, 1.00, 0.90}, + {2.00, 1.50, 1.15, 1.00, 0.85}, + {2.50, 1.75, 1.25, 1.00, 0.80} }; +static const double aq_c_transitions[AQ_C_STRENGTHS][AQ_C_SEGMENTS] = + { {0.15, 0.30, 0.55, 2.00, 100.0}, + {0.20, 0.40, 0.65, 2.00, 100.0}, + {0.25, 0.50, 0.75, 2.00, 100.0} }; +static const double aq_c_var_thresholds[AQ_C_STRENGTHS][AQ_C_SEGMENTS] = + { {-4.0, -3.0, -2.0, 100.00, 100.0}, + {-3.5, -2.5, -1.5, 100.00, 100.0}, + {-3.0, -2.0, -1.0, 100.00, 100.0} }; + +#define DEFAULT_COMPLEXITY 64 + + +static int get_aq_c_strength(int q_index, vpx_bit_depth_t bit_depth) { + // Approximate base quatizer (truncated to int) + const int base_quant = vp9_ac_quant(q_index, 0, bit_depth) / 4; + return (base_quant > 10) + (base_quant > 25); +} + +void vp9_setup_in_frame_q_adj(VP9_COMP *cpi) { + VP9_COMMON *const cm = &cpi->common; + struct segmentation *const seg = &cm->seg; + + // Make SURE use of floating point in this function is safe. + vp9_clear_system_state(); + + if (cm->frame_type == KEY_FRAME || + cpi->refresh_alt_ref_frame || + (cpi->refresh_golden_frame && !cpi->rc.is_src_frame_alt_ref)) { + int segment; + const int aq_strength = get_aq_c_strength(cm->base_qindex, cm->bit_depth); + + // Clear down the segment map. + memset(cpi->segmentation_map, DEFAULT_AQ2_SEG, cm->mi_rows * cm->mi_cols); + + vp9_clearall_segfeatures(seg); + + // Segmentation only makes sense if the target bits per SB is above a + // threshold. Below this the overheads will usually outweigh any benefit. + if (cpi->rc.sb64_target_rate < 256) { + vp9_disable_segmentation(seg); + return; + } + + vp9_enable_segmentation(seg); + + // Select delta coding method. + seg->abs_delta = SEGMENT_DELTADATA; + + // Default segment "Q" feature is disabled so it defaults to the baseline Q. + vp9_disable_segfeature(seg, DEFAULT_AQ2_SEG, SEG_LVL_ALT_Q); + + // Use some of the segments for in frame Q adjustment. + for (segment = 0; segment < AQ_C_SEGMENTS; ++segment) { + int qindex_delta; + + if (segment == DEFAULT_AQ2_SEG) + continue; + + qindex_delta = + vp9_compute_qdelta_by_rate(&cpi->rc, cm->frame_type, cm->base_qindex, + aq_c_q_adj_factor[aq_strength][segment], + cm->bit_depth); + + + // For AQ complexity mode, we dont allow Q0 in a segment if the base + // Q is not 0. Q0 (lossless) implies 4x4 only and in AQ mode 2 a segment + // Q delta is sometimes applied without going back around the rd loop. + // This could lead to an illegal combination of partition size and q. + if ((cm->base_qindex != 0) && ((cm->base_qindex + qindex_delta) == 0)) { + qindex_delta = -cm->base_qindex + 1; + } + if ((cm->base_qindex + qindex_delta) > 0) { + vp9_enable_segfeature(seg, segment, SEG_LVL_ALT_Q); + vp9_set_segdata(seg, segment, SEG_LVL_ALT_Q, qindex_delta); + } + } + } +} + +#define DEFAULT_LV_THRESH 10.0 +#define MIN_DEFAULT_LV_THRESH 8.0 +#define VAR_STRENGTH_STEP 0.25 +// Select a segment for the current block. +// The choice of segment for a block depends on the ratio of the projected +// bits for the block vs a target average and its spatial complexity. +void vp9_caq_select_segment(VP9_COMP *cpi, MACROBLOCK *mb, BLOCK_SIZE bs, + int mi_row, int mi_col, int projected_rate) { + VP9_COMMON *const cm = &cpi->common; + + const int mi_offset = mi_row * cm->mi_cols + mi_col; + const int bw = num_8x8_blocks_wide_lookup[BLOCK_64X64]; + const int bh = num_8x8_blocks_high_lookup[BLOCK_64X64]; + const int xmis = MIN(cm->mi_cols - mi_col, num_8x8_blocks_wide_lookup[bs]); + const int ymis = MIN(cm->mi_rows - mi_row, num_8x8_blocks_high_lookup[bs]); + int x, y; + int i; + unsigned char segment; + + if (0) { + segment = DEFAULT_AQ2_SEG; + } else { + // Rate depends on fraction of a SB64 in frame (xmis * ymis / bw * bh). + // It is converted to bits * 256 units. + const int target_rate = (cpi->rc.sb64_target_rate * xmis * ymis * 256) / + (bw * bh); + double logvar; + double low_var_thresh; + const int aq_strength = get_aq_c_strength(cm->base_qindex, cm->bit_depth); + + vp9_clear_system_state(); + low_var_thresh = (cpi->oxcf.pass == 2) + ? MAX(cpi->twopass.mb_av_energy, MIN_DEFAULT_LV_THRESH) + : DEFAULT_LV_THRESH; + + vp9_setup_src_planes(mb, cpi->Source, mi_row, mi_col); + logvar = vp9_log_block_var(cpi, mb, bs); + + segment = AQ_C_SEGMENTS - 1; // Just in case no break out below. + for (i = 0; i < AQ_C_SEGMENTS; ++i) { + // Test rate against a threshold value and variance against a threshold. + // Increasing segment number (higher variance and complexity) = higher Q. + if ((projected_rate < + target_rate * aq_c_transitions[aq_strength][i]) && + (logvar < (low_var_thresh + aq_c_var_thresholds[aq_strength][i]))) { + segment = i; + break; + } + } + } + + // Fill in the entires in the segment map corresponding to this SB64. + for (y = 0; y < ymis; y++) { + for (x = 0; x < xmis; x++) { + cpi->segmentation_map[mi_offset + y * cm->mi_cols + x] = segment; + } + } +} |