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/******************************************************************************
*
* 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
* ih264_trans_data.h
*
* @brief
* Contains declaration of global variables for H264 transform , qnat and inverse quant
*
* @author
* Ittiam
*
* @remarks
*
*******************************************************************************
*/
#ifndef IH264_GLOBAL_DATA_H_
#define IH264_GLOBAL_DATA_H_
/*****************************************************************************/
/* Extern global declarations */
/*****************************************************************************/
/* Scaling matrices for h264 quantization */
extern const UWORD16 g_scal_coff_h264_4x4[16];
extern const UWORD16 g_scal_coff_h264_8x8[16];
/**
******************************************************************************
* @brief Scale Table for quantizing 4x4 subblock. To quantize a given 4x4 DCT
* transformed block, the coefficient at index location (i,j) is scaled by one of
* the constants in this table and right shift the result by (QP_BITS_h264_4x4 +
* floor(qp/6)), here qp is the quantization parameter used to quantize the mb.
*
* input : qp%6, index location (i,j)
* output : scale constant.
*
* @remarks 16 constants for each index position of the subblock and 6 for each
* qp%6 in the range 0-5 inclusive.
******************************************************************************
*/
extern const UWORD16 gu2_quant_scale_matrix_4x4[96];
/**
******************************************************************************
* @brief Round Factor for quantizing subblock. While quantizing a given 4x4 DCT
* transformed block, the coefficient at index location (i,j) is scaled by one of
* the constants in the table gu2_forward_quant_scalar_4x4 and then right shift
* the result by (QP_BITS_h264_4x4 + floor(qp/6)).
* Before right shifting a round factor is added.
* The round factor can be any value [a * (1 << (QP_BITS_h264_4x4 + floor(qp/6)))]
* for 'a' lies in the range 0-0.5.
* Here qp is the quantization parameter used to quantize the mb.
*
* input : qp/6
* output : round factor.
*
* @remarks The round factor is constructed by setting a = 1/3
******************************************************************************
*/
extern const UWORD32 gu4_forward_quant_round_factor_4x4[9];
/**
******************************************************************************
* @brief Threshold Table. Quantizing the given DCT coefficient is done only if
* it exceeds the threshold value presented in this table.
*
* input : qp/6, qp%6, index location (i,j)
* output : Threshold constant.
*
* @remarks 16 constants for each index position of the subblock and 6 for each
* qp%6 in the range 0-5 inclusive and 9 for each qp/6 in the range 0-51.
******************************************************************************
*/
extern const UWORD16 gu2_forward_quant_threshold_4x4[96];
/**
******************************************************************************
* @brief Scale Table for quantizing 8x8 subblock. To quantize a given 8x8 DCT
* transformed block, the coefficient at index location (i,j) is scaled by one of
* the constants in this table and right shift the result by (QP_BITS_h264_8x8 +
* floor(qp/6)), here qp is the quantization parameter used to quantize the mb.
*
* input : qp%6, index location (i,j)
* output : scale constant.
*
* @remarks 64 constants for each index position of the subblock and 6 for each
* qp%6 in the range 0-5 inclusive.
******************************************************************************
*/
extern const UWORD16 gu2_quant_scale_matrix_8x8 [384];
/**
******************************************************************************
* @brief Specification of QPc as a function of qPi
*
* input : qp luma
* output : qp chroma.
*
* @remarks Refer Table 8-15 of h264 specification.
******************************************************************************
*/
extern const UWORD8 gu1_qpc_fqpi[52];
#endif /* IH264_GLOBAL_DATA_H_ */
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