uvg266/src/context.c
2013-09-19 12:22:26 +03:00

209 lines
7.5 KiB
C

/**
* \file
*
* \author Marko Viitanen ( fador@iki.fi ),
* Tampere University of Technology,
* Department of Pervasive Computing.
* \author Ari Koivula ( ari@koivu.la ),
* Tampere University of Technology,
* Department of Pervasive Computing.
*/
#include "context.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "config.h"
// CONTEXTS
cabac_ctx g_split_flag_model[3]; //!< \brief split flag context models
cabac_ctx g_intra_mode_model; //!< \brief intra mode context models
cabac_ctx g_chroma_pred_model[2];
cabac_ctx g_trans_subdiv_model[3]; //!< \brief intra mode context models
cabac_ctx g_qt_cbf_model_luma[3];
cabac_ctx g_qt_cbf_model_chroma[3];
cabac_ctx g_part_size_model[4];
cabac_ctx g_cu_sig_coeff_group_model[4];
cabac_ctx g_cu_sig_model_luma[27];
cabac_ctx g_cu_sig_model_chroma[15];
cabac_ctx g_cu_ctx_last_y_luma[15];
cabac_ctx g_cu_ctx_last_y_chroma[15];
cabac_ctx g_cu_ctx_last_x_luma[15];
cabac_ctx g_cu_ctx_last_x_chroma[15];
cabac_ctx g_cu_one_model_luma[16];
cabac_ctx g_cu_one_model_chroma[8];
cabac_ctx g_cu_abs_model_luma[4];
cabac_ctx g_cu_abs_model_chroma[2];
cabac_ctx g_cu_pred_mode_model;
cabac_ctx g_cu_skip_flag_model[3];
cabac_ctx g_cu_merge_idx_ext_model;
cabac_ctx g_cu_merge_flag_ext_model;
cabac_ctx g_cu_mvd_model[2];
cabac_ctx g_cu_ref_pic_model[2];
cabac_ctx g_mvp_idx_model[2];
cabac_ctx g_cu_qt_root_cbf_model;
/**
* \brief Initialize cabac context to be used for coding
* \param encoder encoder control struct
* \param slice type of slice we are coding (P/B/I)
*/
void init_contexts(encoder_control *encoder, int8_t slice)
{
uint16_t i;
// Initialize contexts
ctx_init(&g_cu_merge_flag_ext_model, encoder->QP, INIT_MERGE_FLAG_EXT[slice][0]);
ctx_init(&g_cu_merge_idx_ext_model, encoder->QP, INIT_MERGE_IDX_EXT[slice][0]);
ctx_init(&g_cu_pred_mode_model, encoder->QP, INIT_PRED_MODE[slice][0]);
ctx_init(&g_cu_skip_flag_model[0], encoder->QP, INIT_SKIP_FLAG[slice][0]);
ctx_init(&g_cu_skip_flag_model[1], encoder->QP, INIT_SKIP_FLAG[slice][1]);
ctx_init(&g_cu_skip_flag_model[2], encoder->QP, INIT_SKIP_FLAG[slice][2]);
ctx_init(&g_split_flag_model[0], encoder->QP, INIT_SPLIT_FLAG[slice][0]);
ctx_init(&g_split_flag_model[1], encoder->QP, INIT_SPLIT_FLAG[slice][1]);
ctx_init(&g_split_flag_model[2], encoder->QP, INIT_SPLIT_FLAG[slice][2]);
ctx_init(&g_intra_mode_model, encoder->QP, INIT_INTRA_PRED_MODE[slice]);
ctx_init(&g_chroma_pred_model[0], encoder->QP, INIT_CHROMA_PRED_MODE[slice][0]);
ctx_init(&g_chroma_pred_model[1], encoder->QP, INIT_CHROMA_PRED_MODE[slice][1]);
ctx_init(&g_cu_abs_model_chroma[0], encoder->QP, INIT_ABS_FLAG[slice][4]);
ctx_init(&g_cu_abs_model_chroma[1], encoder->QP, INIT_ABS_FLAG[slice][5]);
//TODO: ignore P/B contexts on intra frame
ctx_init(&g_cu_qt_root_cbf_model, encoder->QP, INIT_QT_ROOT_CBF[slice][0]);
ctx_init(&g_cu_mvd_model[0], encoder->QP, INIT_MVD[slice][0]);
ctx_init(&g_cu_mvd_model[1], encoder->QP, INIT_MVD[slice][1]);
ctx_init(&g_cu_ref_pic_model[0], encoder->QP, INIT_REF_PIC[slice][0]);
ctx_init(&g_cu_ref_pic_model[1], encoder->QP, INIT_REF_PIC[slice][1]);
ctx_init(&g_mvp_idx_model[0], encoder->QP, INIT_MVP_IDX[slice][0]);
ctx_init(&g_mvp_idx_model[1], encoder->QP, INIT_MVP_IDX[slice][1]);
for (i = 0; i < 4; i++) {
ctx_init(&g_cu_sig_coeff_group_model[i], encoder->QP, INIT_SIG_CG_FLAG[slice][i]);
ctx_init(&g_cu_abs_model_luma[i], encoder->QP, INIT_ABS_FLAG[slice][i]);
ctx_init(&g_part_size_model[i], encoder->QP, INIT_PART_SIZE[slice][i]);
}
for (i = 0; i < 3; i++) {
ctx_init(&g_trans_subdiv_model[i], encoder->QP, INIT_TRANS_SUBDIV_FLAG[slice][i]);
ctx_init(&g_qt_cbf_model_luma[i], encoder->QP, INIT_QT_CBF[slice][i]);
ctx_init(&g_qt_cbf_model_chroma[i], encoder->QP, INIT_QT_CBF[slice][i+3]);
}
for (i = 0; i < 8; i++) {
ctx_init(&g_cu_one_model_chroma[i], encoder->QP, INIT_ONE_FLAG[slice][i+16]);
}
for (i = 0; i < 15; i++) {
ctx_init(&g_cu_ctx_last_y_luma[i], encoder->QP, INIT_LAST[slice][i] );
ctx_init(&g_cu_ctx_last_x_luma[i], encoder->QP, INIT_LAST[slice][i] );
ctx_init(&g_cu_ctx_last_y_chroma[i], encoder->QP, INIT_LAST[slice][i+15] );
ctx_init(&g_cu_ctx_last_x_chroma[i], encoder->QP, INIT_LAST[slice][i+15] );
ctx_init(&g_cu_one_model_luma[i], encoder->QP, INIT_ONE_FLAG[slice][i]);
}
ctx_init(&g_cu_one_model_luma[15], encoder->QP, INIT_ONE_FLAG[slice][15]);
for (i = 0; i < 27; i++) {
ctx_init(&g_cu_sig_model_luma[i], encoder->QP, INIT_SIG_FLAG[slice][i]);
if(i < 15) ctx_init(&g_cu_sig_model_chroma[i], encoder->QP, INIT_SIG_FLAG[slice][i+27]);
}
}
uint32_t context_get_sig_coeff_group( uint32_t *sig_coeff_group_flag,
uint32_t pos_x,
uint32_t pos_y,
int32_t width)
{
uint32_t uiRight = 0;
uint32_t uiLower = 0;
width >>= 2;
if (pos_x < (uint32_t)width - 1) uiRight = (sig_coeff_group_flag[pos_y * width + pos_x + 1] != 0);
if (pos_y < (uint32_t)width - 1) uiLower = (sig_coeff_group_flag[(pos_y + 1 ) * width + pos_x] != 0);
return uiRight || uiLower;
}
/**
* \brief Pattern decision for context derivation process of significant_coeff_flag
* \param sig_coeff_group_flag pointer to prior coded significant coeff group
* \param pos_x column of current coefficient group
* \param pos_y row of current coefficient group
* \param width width of the block
* \returns pattern for current coefficient group
*/
int32_t context_calc_pattern_sig_ctx(const uint32_t *sig_coeff_group_flag, uint32_t pos_x, uint32_t pos_y, int32_t width)
{
uint32_t sigRight = 0;
uint32_t sigLower = 0;
if (width == 4) return -1;
width >>= 2;
if (pos_x < (uint32_t)width - 1) sigRight = (sig_coeff_group_flag[pos_y * width + pos_x + 1] != 0);
if (pos_y < (uint32_t)width - 1) sigLower = (sig_coeff_group_flag[(pos_y + 1 ) * width + pos_x] != 0);
return sigRight + (sigLower<<1);
}
/**
* \brief Context derivation process of coeff_abs_significant_flag
* \param pattern_sig_ctx pattern for current coefficient group
* \param scan_idx pixel scan type in use
* \param pos_x column of current scan position
* \param pos_y row of current scan position
* \param block_type log2 value of block size if square block, or 4 otherwise
* \param width width of the block
* \param texture_type texture type (TEXT_LUMA...)
* \returns ctx_inc for current scan position
*/
int32_t context_get_sig_ctx_inc(int32_t pattern_sig_ctx, uint32_t scan_idx, int32_t pos_x,
int32_t pos_y, int32_t block_type, int32_t width, int8_t texture_type)
{
const int32_t ctx_ind_map[16] =
{
0, 1, 4, 5,
2, 3, 4, 5,
6, 6, 8, 8,
7, 7, 8, 8
};
int32_t cnt,offset,pos_x_in_subset,pos_y_in_subset;
if (pos_x + pos_y == 0) return 0;
if (block_type == 2) return ctx_ind_map[4 * pos_y + pos_x];
cnt = 0;
offset = (block_type == 3) ? ((scan_idx == SCAN_DIAG) ? 9 : 15) : ((texture_type == 0) ? 21 : 12);
pos_x_in_subset = pos_x - ((pos_x>>2)<<2);
pos_y_in_subset = pos_y - ((pos_y>>2)<<2);
if (pattern_sig_ctx == 0) {
cnt = (pos_x_in_subset + pos_y_in_subset <= 2) ? ((pos_x_in_subset + pos_y_in_subset==0) ? 2 : 1) : 0;
} else if (pattern_sig_ctx==1) {
cnt = (pos_y_in_subset <= 1) ? ((pos_y_in_subset == 0) ? 2 : 1) : 0;
} else if (pattern_sig_ctx==2) {
cnt = (pos_x_in_subset <= 1) ? ((pos_x_in_subset == 0) ? 2 : 1) : 0;
} else {
cnt = 2;
}
return (( texture_type == 0 && ((pos_x>>2) + (pos_y>>2)) > 0 ) ? 3 : 0) + offset + cnt;
}