1/******************************************************************************
2*
3* Copyright (C) 2012 Ittiam Systems Pvt Ltd, Bangalore
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/**
19 *******************************************************************************
20 * @file
21 *  ihevc_chroma_itrans_recon.c
22 *
23 * @brief
24 *  Contains function definitions for inverse transform  and reconstruction
25 * of chroma interleaved data.
26 *
27 * @author
28 *  100470
29 *
30 * @par List of Functions:
31 *  - ihevc_chroma_itrans_recon_4x4()
32 *
33 * @remarks
34 *  None
35 *
36 *******************************************************************************
37 */
38
39#include <stdio.h>
40#include <string.h>
41#include "ihevc_typedefs.h"
42#include "ihevc_macros.h"
43#include "ihevc_platform_macros.h"
44#include "ihevc_defs.h"
45#include "ihevc_trans_tables.h"
46#include "ihevc_chroma_itrans_recon.h"
47#include "ihevc_func_selector.h"
48#include "ihevc_trans_macros.h"
49
50/* All the functions work one component(U or V) of interleaved data depending upon pointers passed to it */
51/* Data visualization */
52/* U V U V U V U V */
53/* U V U V U V U V */
54/* U V U V U V U V */
55/* U V U V U V U V */
56/* If the pointer points to first byte of above stream (U) , functions will operate on U component */
57/* If the pointer points to second byte of above stream (V) , functions will operate on V component */
58
59/**
60 *******************************************************************************
61 *
62 * @brief
63 *  This function performs Inverse transform  and reconstruction for 4x4
64 * input block
65 *
66 * @par Description:
67 *  Performs inverse transform and adds the prediction  data and clips output
68 * to 8 bit
69 *
70 * @param[in] pi2_src
71 *  Input 4x4 coefficients
72 *
73 * @param[in] pi2_tmp
74 *  Temporary 4x4 buffer for storing inverse transform
75 *  1st stage output
76 *
77 * @param[in] pu1_pred
78 *  Prediction 4x4 block
79 *
80 * @param[out] pu1_dst
81 *  Output 4x4 block
82 *
83 * @param[in] src_strd
84 *  Input stride
85 *
86 * @param[in] pred_strd
87 *  Prediction stride
88 *
89 * @param[in] dst_strd
90 *  Output Stride
91 *
92 * @param[in] shift
93 *  Output shift
94 *
95 * @param[in] zero_cols
96 *  Zero columns in pi2_src
97 *
98 * @returns  Void
99 *
100 * @remarks
101 *  None
102 *
103 *******************************************************************************
104 */
105
106
107void ihevc_chroma_itrans_recon_4x4(WORD16 *pi2_src,
108                                   WORD16 *pi2_tmp,
109                                   UWORD8 *pu1_pred,
110                                   UWORD8 *pu1_dst,
111                                   WORD32 src_strd,
112                                   WORD32 pred_strd,
113                                   WORD32 dst_strd,
114                                   WORD32 zero_cols,
115                                   WORD32 zero_rows)
116{
117    WORD32 j;
118    WORD32 e[2], o[2];
119    WORD32 add;
120    WORD32 shift;
121    WORD16 *pi2_tmp_orig;
122    WORD32 trans_size;
123    UNUSED(zero_rows);
124    trans_size = TRANS_SIZE_4;
125
126    pi2_tmp_orig = pi2_tmp;
127
128    /* Inverse Transform 1st stage */
129    shift = IT_SHIFT_STAGE_1;
130    add = 1 << (shift - 1);
131
132    for(j = 0; j < trans_size; j++)
133    {
134        /* Checking for Zero Cols */
135        if((zero_cols & 1) == 1)
136        {
137            memset(pi2_tmp, 0, trans_size * sizeof(WORD16));
138        }
139        else
140        {
141
142            /* Utilizing symmetry properties to the maximum to minimize the number of multiplications */
143            o[0] = g_ai2_ihevc_trans_4[1][0] * pi2_src[src_strd]
144                            + g_ai2_ihevc_trans_4[3][0] * pi2_src[3 * src_strd];
145            o[1] = g_ai2_ihevc_trans_4[1][1] * pi2_src[src_strd]
146                            + g_ai2_ihevc_trans_4[3][1] * pi2_src[3 * src_strd];
147            e[0] = g_ai2_ihevc_trans_4[0][0] * pi2_src[0]
148                            + g_ai2_ihevc_trans_4[2][0] * pi2_src[2 * src_strd];
149            e[1] = g_ai2_ihevc_trans_4[0][1] * pi2_src[0]
150                            + g_ai2_ihevc_trans_4[2][1] * pi2_src[2 * src_strd];
151
152            pi2_tmp[0] =
153                            CLIP_S16(((e[0] + o[0] + add) >> shift));
154            pi2_tmp[1] =
155                            CLIP_S16(((e[1] + o[1] + add) >> shift));
156            pi2_tmp[2] =
157                            CLIP_S16(((e[1] - o[1] + add) >> shift));
158            pi2_tmp[3] =
159                            CLIP_S16(((e[0] - o[0] + add) >> shift));
160
161        }
162        pi2_src++;
163        pi2_tmp += trans_size;
164        zero_cols = zero_cols >> 1;
165    }
166
167    pi2_tmp = pi2_tmp_orig;
168
169    /* Inverse Transform 2nd stage */
170    shift = IT_SHIFT_STAGE_2;
171    add = 1 << (shift - 1);
172
173    for(j = 0; j < trans_size; j++)
174    {
175        WORD32 itrans_out;
176        /* Utilizing symmetry properties to the maximum to minimize the number of multiplications */
177        o[0] = g_ai2_ihevc_trans_4[1][0] * pi2_tmp[trans_size]
178                        + g_ai2_ihevc_trans_4[3][0] * pi2_tmp[3 * trans_size];
179        o[1] = g_ai2_ihevc_trans_4[1][1] * pi2_tmp[trans_size]
180                        + g_ai2_ihevc_trans_4[3][1] * pi2_tmp[3 * trans_size];
181        e[0] = g_ai2_ihevc_trans_4[0][0] * pi2_tmp[0]
182                        + g_ai2_ihevc_trans_4[2][0] * pi2_tmp[2 * trans_size];
183        e[1] = g_ai2_ihevc_trans_4[0][1] * pi2_tmp[0]
184                        + g_ai2_ihevc_trans_4[2][1] * pi2_tmp[2 * trans_size];
185
186        itrans_out =
187                        CLIP_S16(((e[0] + o[0] + add) >> shift));
188        pu1_dst[0 * 2] = CLIP_U8((itrans_out + pu1_pred[0 * 2]));
189        itrans_out =
190                        CLIP_S16(((e[1] + o[1] + add) >> shift));
191        pu1_dst[1 * 2] = CLIP_U8((itrans_out + pu1_pred[1 * 2]));
192        itrans_out =
193                        CLIP_S16(((e[1] - o[1] + add) >> shift));
194        pu1_dst[2 * 2] = CLIP_U8((itrans_out + pu1_pred[2 * 2]));
195        itrans_out =
196                        CLIP_S16(((e[0] - o[0] + add) >> shift));
197        pu1_dst[3 * 2] = CLIP_U8((itrans_out + pu1_pred[3 * 2]));
198
199        pi2_tmp++;
200        pu1_pred += pred_strd;
201        pu1_dst += dst_strd;
202
203    }
204}
205
206