/******************************************************************************
*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*****************************************************************************
* Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore
*/
/*!
***************************************************************************
* \file ih264d_cabac.h
*
* \brief
* This file contains declarations of Binary decoding routines and tables.
*
* \date
* 04/02/2003
*
* \author NS
***************************************************************************
*/
#ifndef _IH264D_CABAC_H_
#define _IH264D_CABAC_H_
#include "ih264_typedefs.h"
#include "ih264_macros.h"
#include "ih264_platform_macros.h"
#include "ih264d_bitstrm.h"
#include "ih264d_defs.h"
#define B_BITS 10
#define HALF (1 << (B_BITS-1))
#define QUARTER (1 << (B_BITS-2))
#define CTXT_UNUSED {0,64}
#define NUM_MB_SKIP_CTXT 6
#define NUM_MB_TYPE_CTXT 9
#define NUM_SUBMB_TYPE_CTXT 7
#define NUM_REF_IDX_CTXT 6
#define NUM_MB_QP_DELTA 4
#define NUM_PRED_MODE 6
#define NUM_MB_FIELD 3
#define NUM_CBP 12
#define NUM_CTX_MVD 14
/* Residual block cabac context parameters */
#define NUM_CTX_CAT 6
#define NUM_LUMA_CTX_CAT 3
#define NUM_CTX_CODED_BLOCK 4
/* Luma CtxSigCoeff + CtxLastCoeff = 15 + 15 = 30 */
#define NUM_LUMA_CTX_SIG_COEF 30
/* Chroma DC CtxSigCoeff + CtxLastCoeff = 3 + 3 = 6 */
#define NUM_CTX_CHROMA_DC_SIG_COEF 6
/* Chroma AC CtxSigCoeff + CtxLastCoeff = 14 + 14 = 28 */
#define NUM_CTX_CHROMA_AC_SIG_COEF 28
#define NUM_CTX_ABS_LEVEL 10
#define LUMA_DC_CTXCAT 0
#define LUMA_AC_CTXCAT 1
#define LUMA_4X4_CTXCAT 2
#define CHROMA_DC_CTXCAT 3
#define CHROMA_AC_CTXCAT 4
#define LUMA_8X8_CTXCAT 5
/*****************************************************************************/
/* Constant Macros */
/*****************************************************************************/
#define NUM_CABAC_CTXTS 460
#define QP_RANGE 52
#define NUM_CAB_INIT_IDC_PLUS_ONE 4
#define LAST_COEFF_CTXT_MINUS_SIG_COEFF_CTXT 61
#define LAST_COEFF_CTXT_MINUS_SIG_COEFF_CTXT_8X8 15
/*bits 0 to 5 :state
bit 6:mps*/
typedef struct
{
UWORD8 u1_mps_state; /* state number */
} bin_ctxt_model_t;
typedef struct
{
/* Neighbour availability Variables needed to get CtxtInc, for CABAC */
UWORD8 u1_mb_type; /** macroblock type: I/P/B/SI/SP */
UWORD8 u1_cbp; /** Coded Block Pattern */
UWORD8 u1_intra_chroma_pred_mode;
/*************************************************************************/
/* Arrangnment of DC CSBP */
/* bits: b7 b6 b5 b4 b3 b2 b1 b0 */
/* CSBP: x x x x x Vdc Udc Ydc */
/*************************************************************************/
UWORD8 u1_yuv_dc_csbp;
WORD8 i1_ref_idx[4];
UWORD8 u1_mv[4][4];
UWORD8 u1_transform8x8_ctxt;
} ctxt_inc_mb_info_t;
#define ONE_RIGHT_SHIFTED_BY_8 1<<8
#define ONE_RIGHT_SHIFTED_BY_9 1<<9
#define ONE_RIGHT_SHIFTED_BY_14 1<<14
typedef struct
{
UWORD32 u4_code_int_range;
UWORD32 u4_code_int_val_ofst;
const void *cabac_table;
void * pv_codec_handle; /* For Error Handling */
} decoding_envirnoment_t;
WORD32 ih264d_init_cabac_dec_envirnoment(decoding_envirnoment_t * ps_cab_env,
dec_bit_stream_t *ps_bitstrm);
UWORD32 ih264d_decode_bin(UWORD32 u4_ctx_inc,
bin_ctxt_model_t *ps_bin_ctxt,
dec_bit_stream_t *ps_bitstrm,
decoding_envirnoment_t *ps_cab_env);
UWORD8 ih264d_decode_terminate(decoding_envirnoment_t * ps_cab_env,
dec_bit_stream_t * ps_bitstrm);
UWORD32 ih264d_decode_bins_tunary(UWORD8 u1_max_bins,
UWORD32 u4_ctx_inc,
bin_ctxt_model_t *ps_src_bin_ctxt,
dec_bit_stream_t *ps_bitstrm,
decoding_envirnoment_t *ps_cab_env);
UWORD32 ih264d_decode_bins(UWORD8 u1_max_bins,
UWORD32 u4_ctx_inc,
bin_ctxt_model_t *ps_src_bin_ctxt,
dec_bit_stream_t *ps_bitstrm,
decoding_envirnoment_t *ps_cab_env);
UWORD32 ih264d_decode_bins_unary(UWORD8 u1_max_bins,
UWORD32 u4_ctx_inc,
bin_ctxt_model_t *ps_src_bin_ctxt,
dec_bit_stream_t *ps_bitstrm,
decoding_envirnoment_t *ps_cab_env);
UWORD32 ih264d_decode_bypass_bins_unary(decoding_envirnoment_t *ps_cab_env,
dec_bit_stream_t *ps_bitstrm);
UWORD32 ih264d_decode_bypass_bins(decoding_envirnoment_t *ps_cab_env,
UWORD8 u1_max_bins,
dec_bit_stream_t *ps_bitstrm);
/*****************************************************************************/
/* Function Macros */
/*****************************************************************************/
/*****************************************************************************/
/* Defining a macro for renormalization*/
/*****************************************************************************/
/*we renormalize every time the number bits(which are read ahead of time) we have
consumed in the u4_ofst exceeds 23*/
#define RENORM_RANGE_OFFSET(u4_codeIntRange_m,u4_codeIntValOffset_m,u4_offset_m,pu4_buffer_m) \
{ \
UWORD32 read_bits_m,u4_clz_m ; \
u4_clz_m = CLZ(u4_codeIntRange_m); \
NEXTBITS(read_bits_m,(u4_offset_m+23),pu4_buffer_m,u4_clz_m) \
FLUSHBITS(u4_offset_m,(u4_clz_m)) \
u4_codeIntRange_m = u4_codeIntRange_m << u4_clz_m; \
u4_codeIntValOffset_m = (u4_codeIntValOffset_m << u4_clz_m) | read_bits_m; \
}
/*****************************************************************************/
/* Defining a macro for checking if the symbol is MPS*/
/*****************************************************************************/
#define CHECK_IF_LPS(u4_codeIntRange_m,u4_codeIntValOffset_m,u4_symbol_m, \
u4_codeIntRangeLPS_m,u1_mps_state_m,table_lookup_m) \
{ \
if(u4_codeIntValOffset_m >= u4_codeIntRange_m) \
{ \
u4_symbol_m = 1 - u4_symbol_m; \
u4_codeIntValOffset_m -= u4_codeIntRange_m; \
u4_codeIntRange_m = u4_codeIntRangeLPS_m; \
u1_mps_state_m = (table_lookup_m >> 15) & 0x7F; \
} \
}
/*!
**************************************************************************
* \if Function name : DECODE_ONE_BIN_MACRO \endif
*
* \brief
* This function implements decoding process of a decision as defined
* in 9.3.3.2.2.
*
* \return
* Returns symbol decoded.
*
* \note
* It is specified in 9.3.3.2.3.2 that, one of the input to this function
* is CtxIdx. CtxIdx is used to identify state and MPS of that context
* (Refer Fig 9.11 - Flowchart for encoding a decision). To suffice that
* here we pass a pointer bin_ctxt_model_t which contains these values.
*
**************************************************************************
*/
#define DECODE_ONE_BIN_MACRO(p_binCtxt_arg ,u4_code_int_range,u4_code_int_val_ofst, \
pu4_table_arg, \
p_DecBitStream_arg,u4_symbol) \
{ \
bin_ctxt_model_t *p_binCtxt_m = (bin_ctxt_model_t *) p_binCtxt_arg; \
dec_bit_stream_t *p_DecBitStream_m = (dec_bit_stream_t *) p_DecBitStream_arg; \
const UWORD32 *pu4_table_m = (const UWORD32 *) pu4_table_arg; \
\
UWORD32 u4_quantCodeIntRange_m,u4_codeIntRangeLPS_m; \
UWORD32 u1_mps_state_m; \
UWORD32 table_lookup_m; \
UWORD32 u4_clz_m; \
\
u1_mps_state_m = (p_binCtxt_m->u1_mps_state); \
u4_clz_m = CLZ(u4_code_int_range); \
u4_quantCodeIntRange_m = u4_code_int_range << u4_clz_m; \
u4_quantCodeIntRange_m = (u4_quantCodeIntRange_m >> 29) & 0x3; \
table_lookup_m = pu4_table_m[(u1_mps_state_m << 2)+u4_quantCodeIntRange_m]; \
u4_codeIntRangeLPS_m = table_lookup_m & 0xff; \
\
u4_codeIntRangeLPS_m = u4_codeIntRangeLPS_m << (23 - u4_clz_m); \
u4_code_int_range = u4_code_int_range - u4_codeIntRangeLPS_m; \
u4_symbol = ((u1_mps_state_m>> 6) & 0x1); \
/*if mps*/ \
u1_mps_state_m = (table_lookup_m >> 8) & 0x7F; \
if(u4_code_int_val_ofst >= u4_code_int_range) \
{ \
\
u4_symbol = 1 - u4_symbol; \
u4_code_int_val_ofst -= u4_code_int_range; \
u4_code_int_range = u4_codeIntRangeLPS_m; \
u1_mps_state_m = (table_lookup_m >> 15) & 0x7F; \
} \
if(u4_code_int_range < ONE_RIGHT_SHIFTED_BY_8) \
{ \
UWORD32 *pu4_buffer,u4_offset; \
UWORD32 read_bits,u4_clz_m ; \
\
pu4_buffer = p_DecBitStream_m->pu4_buffer; \
u4_offset = p_DecBitStream_m->u4_ofst; \
u4_clz_m = CLZ(u4_code_int_range); \
NEXTBITS(read_bits,(u4_offset+23),pu4_buffer,u4_clz_m) \
FLUSHBITS(u4_offset,(u4_clz_m)) \
u4_code_int_range = u4_code_int_range << u4_clz_m; \
u4_code_int_val_ofst= (u4_code_int_val_ofst << u4_clz_m) | read_bits; \
\
\
p_DecBitStream_m->u4_ofst = u4_offset; \
} \
p_binCtxt_m->u1_mps_state = u1_mps_state_m; \
}
#endif /* _IH264D_CABAC_H_ */