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 #include "iv_datatypedef.h"
22 #include "impeg2_defs.h"
23 #include "impeg2_globals.h"
24 #include "impeg2_platform_macros.h"
25 #include "impeg2_inter_pred.h"
26 #include "impeg2_idct.h"
27 #include "impeg2_mem_func.h"
28 #include "impeg2_format_conv.h"
29 #include "impeg2_disp_mgr.h"
30 #include "impeg2_buf_mgr.h"
31
32 #include "impeg2d.h"
33 #include "impeg2d_bitstream.h"
34 #include "impeg2d_structs.h"
35 #include "impeg2d_vld.h"
36 #include "impeg2d_vld_tables.h"
37
38 #define BLK_SIZE 8
39 #define LUMA_BLK_SIZE (2 * (BLK_SIZE))
40 #define CHROMA_BLK_SIZE (BLK_SIZE)
41 /*****************************************************************************/
42 /* */
43 /* Function Name : impeg2d_get_luma_dc_diff */
44 /* */
45 /* Description : Decode the DC differential value from the bitstream for */
46 /* luma block */
47 /* */
48 /* Inputs : stream - Input stream */
49 /* */
50 /* Globals : None */
51 /* */
52 /* Processing : Decode the vlc for dc_diff */
53 /* */
54 /* Outputs : dc_diff - dc differential used in dc prediction */
55 /* */
56 /* Returns : dc_diff - dc differential used in dc prediction */
57 /* */
58 /* Issues : None */
59 /* */
60 /* Revision History: */
61 /* */
62 /* DD MM YYYY Author(s) Changes */
63 /* 14 09 2005 Harish M First Version */
64 /* */
65 /*****************************************************************************/
impeg2d_get_luma_dc_diff(stream_t * ps_stream)66 WORD16 impeg2d_get_luma_dc_diff(stream_t *ps_stream)
67 {
68 UWORD16 u2_dc_size;
69 WORD16 i2_dc_diff;
70
71 u2_dc_size = impeg2d_dec_vld_symbol(ps_stream,gai2_impeg2d_dct_dc_size[0],
72 MPEG2_DCT_DC_LUMA_SIZE_LEN) +
73 MPEG2_DCT_DC_SIZE_OFFSET;
74 if (u2_dc_size != 0)
75 {
76 i2_dc_diff = impeg2d_bit_stream_get(ps_stream,u2_dc_size);
77 if ((i2_dc_diff & (1 << (u2_dc_size - 1))) == 0)
78 i2_dc_diff -= (1 << u2_dc_size) - 1;
79 }
80 else
81 {
82 i2_dc_diff = 0;
83 }
84 return i2_dc_diff;
85 }
86
87 /*****************************************************************************/
88 /* */
89 /* Function Name : impeg2d_get_chroma_dc_diff */
90 /* */
91 /* Description : Decode the DC differential value from the bitstream for */
92 /* chroma block */
93 /* */
94 /* Inputs : stream - Input stream */
95 /* */
96 /* Globals : None */
97 /* */
98 /* Processing : Decode the vlc for dc_diff */
99 /* */
100 /* Outputs : dc_diff - dc differential used in dc prediction */
101 /* */
102 /* Returns : dc_diff - dc differential used in dc prediction */
103 /* */
104 /* Issues : None */
105 /* */
106 /* Revision History: */
107 /* */
108 /* DD MM YYYY Author(s) Changes */
109 /* 14 09 2005 Harish M First Version */
110 /* */
111 /*****************************************************************************/
impeg2d_get_chroma_dc_diff(stream_t * ps_stream)112 WORD16 impeg2d_get_chroma_dc_diff(stream_t *ps_stream)
113 {
114 UWORD16 u2_dc_size;
115 WORD16 i2_dc_diff;
116 u2_dc_size = impeg2d_dec_vld_symbol(ps_stream,gai2_impeg2d_dct_dc_size[1],
117 MPEG2_DCT_DC_CHROMA_SIZE_LEN) +
118 MPEG2_DCT_DC_SIZE_OFFSET;
119 if (u2_dc_size != 0)
120 {
121 i2_dc_diff = impeg2d_bit_stream_get(ps_stream,u2_dc_size);
122 if ((i2_dc_diff & (1 << (u2_dc_size - 1))) == 0)
123 i2_dc_diff -= (1 << u2_dc_size) - 1;
124 }
125 else
126 {
127 i2_dc_diff = 0;
128 }
129 return i2_dc_diff;
130 }
131 /*******************************************************************************
132 * Function Name : impeg2d_dec_d_slice
133 *
134 * Description : Decodes I slice
135 *
136 * Arguments :
137 * dec : Decoder state
138 *
139 * Values Returned : None
140 *******************************************************************************/
impeg2d_dec_d_slice(dec_state_t * ps_dec)141 IMPEG2D_ERROR_CODES_T impeg2d_dec_d_slice(dec_state_t *ps_dec)
142 {
143 UWORD32 i;
144 yuv_buf_t *ps_cur_frm_buf = &ps_dec->s_cur_frm_buf;
145
146 stream_t *ps_stream = &ps_dec->s_bit_stream;
147 UWORD8 *pu1_vld_buf;
148
149 WORD16 i2_dc_diff;
150 UWORD32 u4_frame_width = ps_dec->u2_frame_width;
151 UWORD32 u4_frm_offset = 0;
152 if(ps_dec->u2_picture_structure != FRAME_PICTURE)
153 {
154 u4_frame_width <<= 1;
155 if(ps_dec->u2_picture_structure == BOTTOM_FIELD)
156 {
157 u4_frm_offset = ps_dec->u2_frame_width;
158 }
159 }
160
161 do
162 {
163
164 UWORD32 u4_x_offset, u4_y_offset;
165 UWORD32 u4_blk_pos;
166 WORD16 i2_dc_val;
167
168 UWORD32 u4_dst_x_offset = u4_frm_offset + (ps_dec->u2_mb_x << 4);
169 UWORD32 u4_dst_y_offset = (ps_dec->u2_mb_y << 4) * u4_frame_width;
170 UWORD8 *pu1_vld_buf8 = ps_cur_frm_buf->pu1_y + u4_dst_x_offset + u4_dst_y_offset;
171 UWORD32 u4_dst_wd = u4_frame_width;
172 /*------------------------------------------------------------------*/
173 /* Discard the Macroblock stuffing in case of MPEG-1 stream */
174 /*------------------------------------------------------------------*/
175 while(impeg2d_bit_stream_nxt(ps_stream,MB_STUFFING_CODE_LEN) == MB_STUFFING_CODE &&
176 ps_stream->u4_offset < ps_stream->u4_max_offset)
177 impeg2d_bit_stream_flush(ps_stream,MB_STUFFING_CODE_LEN);
178
179 /*------------------------------------------------------------------*/
180 /* Flush 2 bits from bitstream [MB_Type and MacroBlockAddrIncrement]*/
181 /*------------------------------------------------------------------*/
182 impeg2d_bit_stream_flush(ps_stream,1);
183
184 if(impeg2d_bit_stream_get(ps_stream, 1) != 0x01)
185 {
186 /* Ignore and continue decoding. */
187 }
188
189 /* Process LUMA blocks of the MB */
190 for(i = 0; i < NUM_LUMA_BLKS; ++i)
191 {
192
193 u4_x_offset = gai2_impeg2_blk_x_off[i];
194 u4_y_offset = gai2_impeg2_blk_y_off_frm[i] ;
195 u4_blk_pos = (u4_y_offset * u4_dst_wd) + u4_x_offset;
196 pu1_vld_buf = pu1_vld_buf8 + u4_blk_pos;
197
198 i2_dc_diff = impeg2d_get_luma_dc_diff(ps_stream);
199 i2_dc_val = ps_dec->u2_def_dc_pred[Y_LUMA] + i2_dc_diff;
200 ps_dec->u2_def_dc_pred[Y_LUMA] = i2_dc_val;
201 i2_dc_val = CLIP_U8(i2_dc_val);
202
203 ps_dec->pf_memset_8bit_8x8_block(pu1_vld_buf, i2_dc_val, u4_dst_wd);
204 }
205
206
207
208 /* Process U block of the MB */
209
210 u4_dst_x_offset >>= 1;
211 u4_dst_y_offset >>= 2;
212 u4_dst_wd >>= 1;
213 pu1_vld_buf = ps_cur_frm_buf->pu1_u + u4_dst_x_offset + u4_dst_y_offset;
214 i2_dc_diff = impeg2d_get_chroma_dc_diff(ps_stream);
215 i2_dc_val = ps_dec->u2_def_dc_pred[U_CHROMA] + i2_dc_diff;
216 ps_dec->u2_def_dc_pred[U_CHROMA] = i2_dc_val;
217 i2_dc_val = CLIP_U8(i2_dc_val);
218 ps_dec->pf_memset_8bit_8x8_block(pu1_vld_buf, i2_dc_val, u4_dst_wd);
219
220
221 /* Process V block of the MB */
222
223 pu1_vld_buf = ps_cur_frm_buf->pu1_v + u4_dst_x_offset + u4_dst_y_offset;
224 i2_dc_diff = impeg2d_get_chroma_dc_diff(ps_stream);
225 i2_dc_val = ps_dec->u2_def_dc_pred[V_CHROMA] + i2_dc_diff;
226 ps_dec->u2_def_dc_pred[V_CHROMA] = i2_dc_val;
227 i2_dc_val = CLIP_U8(i2_dc_val);
228 ps_dec->pf_memset_8bit_8x8_block(pu1_vld_buf, i2_dc_val, u4_dst_wd);
229
230 /* Common MB processing Steps */
231
232
233 ps_dec->u2_num_mbs_left--;
234 ps_dec->u2_mb_x++;
235
236 if(ps_dec->s_bit_stream.u4_offset > ps_dec->s_bit_stream.u4_max_offset)
237 {
238 return IMPEG2D_BITSTREAM_BUFF_EXCEEDED_ERR;
239 }
240 else if (ps_dec->u2_mb_x == ps_dec->u2_num_horiz_mb)
241 {
242 ps_dec->u2_mb_x = 0;
243 ps_dec->u2_mb_y++;
244
245 }
246
247 /* Flush end of macro block */
248 impeg2d_bit_stream_flush(ps_stream,1);
249 }
250 while(ps_dec->u2_num_mbs_left != 0 && impeg2d_bit_stream_nxt(&ps_dec->s_bit_stream,23) != 0x0);
251 return (IMPEG2D_ERROR_CODES_T)IVD_ERROR_NONE;
252 }/* End of impeg2d_dec_d_slice() */
253