Hamsalekha S | 8d3d303 | 2015-03-13 21:24:58 +0530 | [diff] [blame] | 1 | /****************************************************************************** |
| 2 | * |
| 3 | * Copyright (C) 2015 The Android Open Source Project |
| 4 | * |
| 5 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | * you may not use this file except in compliance with the License. |
| 7 | * You may obtain a copy of the License at: |
| 8 | * |
| 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | * |
| 11 | * Unless required by applicable law or agreed to in writing, software |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | * See the License for the specific language governing permissions and |
| 15 | * limitations under the License. |
| 16 | * |
| 17 | ***************************************************************************** |
| 18 | * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore |
| 19 | */ |
| 20 | /** |
| 21 | ******************************************************************************* |
| 22 | * @file |
| 23 | * ih264_trans_data.h |
| 24 | * |
| 25 | * @brief |
| 26 | * Contains declaration of global variables for H264 transform , qnat and inverse quant |
| 27 | * |
| 28 | * @author |
| 29 | * Ittiam |
| 30 | * |
| 31 | * @remarks |
| 32 | * |
| 33 | ******************************************************************************* |
| 34 | */ |
| 35 | #ifndef IH264_GLOBAL_DATA_H_ |
| 36 | #define IH264_GLOBAL_DATA_H_ |
| 37 | |
| 38 | /*****************************************************************************/ |
| 39 | /* Extern global declarations */ |
| 40 | /*****************************************************************************/ |
| 41 | |
| 42 | /* Scaling matrices for h264 quantization */ |
| 43 | extern const UWORD16 g_scal_coff_h264_4x4[16]; |
| 44 | extern const UWORD16 g_scal_coff_h264_8x8[16]; |
| 45 | |
| 46 | |
| 47 | /** |
| 48 | ****************************************************************************** |
| 49 | * @brief Scale Table for quantizing 4x4 subblock. To quantize a given 4x4 DCT |
| 50 | * transformed block, the coefficient at index location (i,j) is scaled by one of |
| 51 | * the constants in this table and right shift the result by (QP_BITS_h264_4x4 + |
| 52 | * floor(qp/6)), here qp is the quantization parameter used to quantize the mb. |
| 53 | * |
| 54 | * input : qp%6, index location (i,j) |
| 55 | * output : scale constant. |
| 56 | * |
| 57 | * @remarks 16 constants for each index position of the subblock and 6 for each |
| 58 | * qp%6 in the range 0-5 inclusive. |
| 59 | ****************************************************************************** |
| 60 | */ |
| 61 | extern const UWORD16 gu2_quant_scale_matrix_4x4[96]; |
| 62 | |
| 63 | /** |
| 64 | ****************************************************************************** |
| 65 | * @brief Round Factor for quantizing subblock. While quantizing a given 4x4 DCT |
| 66 | * transformed block, the coefficient at index location (i,j) is scaled by one of |
| 67 | * the constants in the table gu2_forward_quant_scalar_4x4 and then right shift |
| 68 | * the result by (QP_BITS_h264_4x4 + floor(qp/6)). |
| 69 | * Before right shifting a round factor is added. |
| 70 | * The round factor can be any value [a * (1 << (QP_BITS_h264_4x4 + floor(qp/6)))] |
| 71 | * for 'a' lies in the range 0-0.5. |
| 72 | * Here qp is the quantization parameter used to quantize the mb. |
| 73 | * |
| 74 | * input : qp/6 |
| 75 | * output : round factor. |
| 76 | * |
| 77 | * @remarks The round factor is constructed by setting a = 1/3 |
| 78 | ****************************************************************************** |
| 79 | */ |
| 80 | extern const UWORD32 gu4_forward_quant_round_factor_4x4[9]; |
| 81 | |
| 82 | /** |
| 83 | ****************************************************************************** |
| 84 | * @brief Threshold Table. Quantizing the given DCT coefficient is done only if |
| 85 | * it exceeds the threshold value presented in this table. |
| 86 | * |
| 87 | * input : qp/6, qp%6, index location (i,j) |
| 88 | * output : Threshold constant. |
| 89 | * |
| 90 | * @remarks 16 constants for each index position of the subblock and 6 for each |
| 91 | * qp%6 in the range 0-5 inclusive and 9 for each qp/6 in the range 0-51. |
| 92 | ****************************************************************************** |
| 93 | */ |
| 94 | extern const UWORD16 gu2_forward_quant_threshold_4x4[96]; |
| 95 | |
| 96 | /** |
| 97 | ****************************************************************************** |
| 98 | * @brief Scale Table for quantizing 8x8 subblock. To quantize a given 8x8 DCT |
| 99 | * transformed block, the coefficient at index location (i,j) is scaled by one of |
| 100 | * the constants in this table and right shift the result by (QP_BITS_h264_8x8 + |
| 101 | * floor(qp/6)), here qp is the quantization parameter used to quantize the mb. |
| 102 | * |
| 103 | * input : qp%6, index location (i,j) |
| 104 | * output : scale constant. |
| 105 | * |
| 106 | * @remarks 64 constants for each index position of the subblock and 6 for each |
| 107 | * qp%6 in the range 0-5 inclusive. |
| 108 | ****************************************************************************** |
| 109 | */ |
| 110 | extern const UWORD16 gu2_quant_scale_matrix_8x8 [384]; |
| 111 | |
| 112 | /** |
| 113 | ****************************************************************************** |
| 114 | * @brief Specification of QPc as a function of qPi |
| 115 | * |
| 116 | * input : qp luma |
| 117 | * output : qp chroma. |
| 118 | * |
| 119 | * @remarks Refer Table 8-15 of h264 specification. |
| 120 | ****************************************************************************** |
| 121 | */ |
| 122 | extern const UWORD8 gu1_qpc_fqpi[52]; |
| 123 | |
| 124 | |
| 125 | #endif /* IH264_GLOBAL_DATA_H_ */ |