]> git.sesse.net Git - ffmpeg/blob - libavcodec/mpeg4video.c
Merge commit '67bb3a4e285a5871770cbaa2d78bf9024961dd0f'
[ffmpeg] / libavcodec / mpeg4video.c
1 /*
2  * MPEG4 decoder / encoder common code.
3  * Copyright (c) 2000,2001 Fabrice Bellard
4  * Copyright (c) 2002-2010 Michael Niedermayer <michaelni@gmx.at>
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22
23 #include "mpegvideo.h"
24 #include "mpeg4video.h"
25 #include "mpeg4data.h"
26
27 uint8_t ff_mpeg4_static_rl_table_store[3][2][2 * MAX_RUN + MAX_LEVEL + 3];
28
29 int ff_mpeg4_get_video_packet_prefix_length(MpegEncContext *s)
30 {
31     switch (s->pict_type) {
32     case AV_PICTURE_TYPE_I:
33         return 16;
34     case AV_PICTURE_TYPE_P:
35     case AV_PICTURE_TYPE_S:
36         return s->f_code + 15;
37     case AV_PICTURE_TYPE_B:
38         return FFMAX3(s->f_code, s->b_code, 2) + 15;
39     default:
40         return -1;
41     }
42 }
43
44 void ff_mpeg4_clean_buffers(MpegEncContext *s)
45 {
46     int c_wrap, c_xy, l_wrap, l_xy;
47
48     l_wrap = s->b8_stride;
49     l_xy   = (2 * s->mb_y - 1) * l_wrap + s->mb_x * 2 - 1;
50     c_wrap = s->mb_stride;
51     c_xy   = (s->mb_y - 1) * c_wrap + s->mb_x - 1;
52
53 #if 0
54     /* clean DC */
55     memsetw(s->dc_val[0] + l_xy, 1024, l_wrap * 2 + 1);
56     memsetw(s->dc_val[1] + c_xy, 1024, c_wrap + 1);
57     memsetw(s->dc_val[2] + c_xy, 1024, c_wrap + 1);
58 #endif
59
60     /* clean AC */
61     memset(s->ac_val[0] + l_xy, 0, (l_wrap * 2 + 1) * 16 * sizeof(int16_t));
62     memset(s->ac_val[1] + c_xy, 0, (c_wrap     + 1) * 16 * sizeof(int16_t));
63     memset(s->ac_val[2] + c_xy, 0, (c_wrap     + 1) * 16 * sizeof(int16_t));
64
65     /* clean MV */
66     // we can't clear the MVs as they might be needed by a b frame
67 //    memset(s->motion_val + l_xy, 0, (l_wrap * 2 + 1) * 2 * sizeof(int16_t));
68 //    memset(s->motion_val, 0, 2 * sizeof(int16_t) * (2 + s->mb_width * 2) *
69 //           (2 + s->mb_height * 2));
70     s->last_mv[0][0][0] =
71     s->last_mv[0][0][1] =
72     s->last_mv[1][0][0] =
73     s->last_mv[1][0][1] = 0;
74 }
75
76 #define tab_size ((signed)FF_ARRAY_ELEMS(s->direct_scale_mv[0]))
77 #define tab_bias (tab_size / 2)
78
79 // used by mpeg4 and rv10 decoder
80 void ff_mpeg4_init_direct_mv(MpegEncContext *s)
81 {
82     int i;
83     for (i = 0; i < tab_size; i++) {
84         s->direct_scale_mv[0][i] = (i - tab_bias) * s->pb_time / s->pp_time;
85         s->direct_scale_mv[1][i] = (i - tab_bias) * (s->pb_time - s->pp_time) /
86                                    s->pp_time;
87     }
88 }
89
90 static inline void ff_mpeg4_set_one_direct_mv(MpegEncContext *s, int mx,
91                                               int my, int i)
92 {
93     int xy           = s->block_index[i];
94     uint16_t time_pp = s->pp_time;
95     uint16_t time_pb = s->pb_time;
96     int p_mx, p_my;
97
98     p_mx = s->next_picture.motion_val[0][xy][0];
99     if ((unsigned)(p_mx + tab_bias) < tab_size) {
100         s->mv[0][i][0] = s->direct_scale_mv[0][p_mx + tab_bias] + mx;
101         s->mv[1][i][0] = mx ? s->mv[0][i][0] - p_mx
102                             : s->direct_scale_mv[1][p_mx + tab_bias];
103     } else {
104         s->mv[0][i][0] = p_mx * time_pb / time_pp + mx;
105         s->mv[1][i][0] = mx ? s->mv[0][i][0] - p_mx
106                             : p_mx * (time_pb - time_pp) / time_pp;
107     }
108     p_my = s->next_picture.motion_val[0][xy][1];
109     if ((unsigned)(p_my + tab_bias) < tab_size) {
110         s->mv[0][i][1] = s->direct_scale_mv[0][p_my + tab_bias] + my;
111         s->mv[1][i][1] = my ? s->mv[0][i][1] - p_my
112                             : s->direct_scale_mv[1][p_my + tab_bias];
113     } else {
114         s->mv[0][i][1] = p_my * time_pb / time_pp + my;
115         s->mv[1][i][1] = my ? s->mv[0][i][1] - p_my
116                             : p_my * (time_pb - time_pp) / time_pp;
117     }
118 }
119
120 #undef tab_size
121 #undef tab_bias
122
123 /**
124  * @return the mb_type
125  */
126 int ff_mpeg4_set_direct_mv(MpegEncContext *s, int mx, int my)
127 {
128     const int mb_index          = s->mb_x + s->mb_y * s->mb_stride;
129     const int colocated_mb_type = s->next_picture.mb_type[mb_index];
130     uint16_t time_pp;
131     uint16_t time_pb;
132     int i;
133
134     // FIXME avoid divides
135     // try special case with shifts for 1 and 3 B-frames?
136
137     if (IS_8X8(colocated_mb_type)) {
138         s->mv_type = MV_TYPE_8X8;
139         for (i = 0; i < 4; i++)
140             ff_mpeg4_set_one_direct_mv(s, mx, my, i);
141         return MB_TYPE_DIRECT2 | MB_TYPE_8x8 | MB_TYPE_L0L1;
142     } else if (IS_INTERLACED(colocated_mb_type)) {
143         s->mv_type = MV_TYPE_FIELD;
144         for (i = 0; i < 2; i++) {
145             int field_select = s->next_picture.ref_index[0][4 * mb_index + 2 * i];
146             s->field_select[0][i] = field_select;
147             s->field_select[1][i] = i;
148             if (s->top_field_first) {
149                 time_pp = s->pp_field_time - field_select + i;
150                 time_pb = s->pb_field_time - field_select + i;
151             } else {
152                 time_pp = s->pp_field_time + field_select - i;
153                 time_pb = s->pb_field_time + field_select - i;
154             }
155             s->mv[0][i][0] = s->p_field_mv_table[i][0][mb_index][0] *
156                              time_pb / time_pp + mx;
157             s->mv[0][i][1] = s->p_field_mv_table[i][0][mb_index][1] *
158                              time_pb / time_pp + my;
159             s->mv[1][i][0] = mx ? s->mv[0][i][0] -
160                                   s->p_field_mv_table[i][0][mb_index][0]
161                                 : s->p_field_mv_table[i][0][mb_index][0] *
162                                   (time_pb - time_pp) / time_pp;
163             s->mv[1][i][1] = my ? s->mv[0][i][1] -
164                                   s->p_field_mv_table[i][0][mb_index][1]
165                                 : s->p_field_mv_table[i][0][mb_index][1] *
166                                   (time_pb - time_pp) / time_pp;
167         }
168         return MB_TYPE_DIRECT2 | MB_TYPE_16x8 |
169                MB_TYPE_L0L1    | MB_TYPE_INTERLACED;
170     } else {
171         ff_mpeg4_set_one_direct_mv(s, mx, my, 0);
172         s->mv[0][1][0] =
173         s->mv[0][2][0] =
174         s->mv[0][3][0] = s->mv[0][0][0];
175         s->mv[0][1][1] =
176         s->mv[0][2][1] =
177         s->mv[0][3][1] = s->mv[0][0][1];
178         s->mv[1][1][0] =
179         s->mv[1][2][0] =
180         s->mv[1][3][0] = s->mv[1][0][0];
181         s->mv[1][1][1] =
182         s->mv[1][2][1] =
183         s->mv[1][3][1] = s->mv[1][0][1];
184         if ((s->avctx->workaround_bugs & FF_BUG_DIRECT_BLOCKSIZE) ||
185             !s->quarter_sample)
186             s->mv_type = MV_TYPE_16X16;
187         else
188             s->mv_type = MV_TYPE_8X8;
189         // Note see prev line
190         return MB_TYPE_DIRECT2 | MB_TYPE_16x16 | MB_TYPE_L0L1;
191     }
192 }