avcodec/dump_extradata_bsf: don't allocate a new AVPacket per filtered packet
[ffmpeg.git] / libavcodec / mpeg4video.c
1 /*
2  * MPEG-4 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 "mpegutils.h"
24 #include "mpegvideo.h"
25 #include "mpeg4video.h"
26 #include "mpeg4data.h"
27
28 uint8_t ff_mpeg4_static_rl_table_store[3][2][2 * MAX_RUN + MAX_LEVEL + 3];
29
30 int ff_mpeg4_get_video_packet_prefix_length(MpegEncContext *s)
31 {
32     switch (s->pict_type) {
33     case AV_PICTURE_TYPE_I:
34         return 16;
35     case AV_PICTURE_TYPE_P:
36     case AV_PICTURE_TYPE_S:
37         return s->f_code + 15;
38     case AV_PICTURE_TYPE_B:
39         return FFMAX3(s->f_code, s->b_code, 2) + 15;
40     default:
41         return -1;
42     }
43 }
44
45 void ff_mpeg4_clean_buffers(MpegEncContext *s)
46 {
47     int c_wrap, c_xy, l_wrap, l_xy;
48
49     l_wrap = s->b8_stride;
50     l_xy   = (2 * s->mb_y - 1) * l_wrap + s->mb_x * 2 - 1;
51     c_wrap = s->mb_stride;
52     c_xy   = (s->mb_y - 1) * c_wrap + s->mb_x - 1;
53
54     /* clean AC */
55     memset(s->ac_val[0] + l_xy, 0, (l_wrap * 2 + 1) * 16 * sizeof(int16_t));
56     memset(s->ac_val[1] + c_xy, 0, (c_wrap     + 1) * 16 * sizeof(int16_t));
57     memset(s->ac_val[2] + c_xy, 0, (c_wrap     + 1) * 16 * sizeof(int16_t));
58
59     /* clean MV */
60     // we can't clear the MVs as they might be needed by a B-frame
61     s->last_mv[0][0][0] =
62     s->last_mv[0][0][1] =
63     s->last_mv[1][0][0] =
64     s->last_mv[1][0][1] = 0;
65 }
66
67 #define tab_size ((signed)FF_ARRAY_ELEMS(s->direct_scale_mv[0]))
68 #define tab_bias (tab_size / 2)
69
70 // used by MPEG-4 and rv10 decoder
71 void ff_mpeg4_init_direct_mv(MpegEncContext *s)
72 {
73     int i;
74     for (i = 0; i < tab_size; i++) {
75         s->direct_scale_mv[0][i] = (i - tab_bias) * s->pb_time / s->pp_time;
76         s->direct_scale_mv[1][i] = (i - tab_bias) * (s->pb_time - s->pp_time) /
77                                    s->pp_time;
78     }
79 }
80
81 static inline void ff_mpeg4_set_one_direct_mv(MpegEncContext *s, int mx,
82                                               int my, int i)
83 {
84     int xy           = s->block_index[i];
85     uint16_t time_pp = s->pp_time;
86     uint16_t time_pb = s->pb_time;
87     int p_mx, p_my;
88
89     p_mx = s->next_picture.motion_val[0][xy][0];
90     if ((unsigned)(p_mx + tab_bias) < tab_size) {
91         s->mv[0][i][0] = s->direct_scale_mv[0][p_mx + tab_bias] + mx;
92         s->mv[1][i][0] = mx ? s->mv[0][i][0] - p_mx
93                             : s->direct_scale_mv[1][p_mx + tab_bias];
94     } else {
95         s->mv[0][i][0] = p_mx * time_pb / time_pp + mx;
96         s->mv[1][i][0] = mx ? s->mv[0][i][0] - p_mx
97                             : p_mx * (time_pb - time_pp) / time_pp;
98     }
99     p_my = s->next_picture.motion_val[0][xy][1];
100     if ((unsigned)(p_my + tab_bias) < tab_size) {
101         s->mv[0][i][1] = s->direct_scale_mv[0][p_my + tab_bias] + my;
102         s->mv[1][i][1] = my ? s->mv[0][i][1] - p_my
103                             : s->direct_scale_mv[1][p_my + tab_bias];
104     } else {
105         s->mv[0][i][1] = p_my * time_pb / time_pp + my;
106         s->mv[1][i][1] = my ? s->mv[0][i][1] - p_my
107                             : p_my * (time_pb - time_pp) / time_pp;
108     }
109 }
110
111 #undef tab_size
112 #undef tab_bias
113
114 /**
115  * @return the mb_type
116  */
117 int ff_mpeg4_set_direct_mv(MpegEncContext *s, int mx, int my)
118 {
119     const int mb_index          = s->mb_x + s->mb_y * s->mb_stride;
120     const int colocated_mb_type = s->next_picture.mb_type[mb_index];
121     uint16_t time_pp;
122     uint16_t time_pb;
123     int i;
124
125     // FIXME avoid divides
126     // try special case with shifts for 1 and 3 B-frames?
127
128     if (IS_8X8(colocated_mb_type)) {
129         s->mv_type = MV_TYPE_8X8;
130         for (i = 0; i < 4; i++)
131             ff_mpeg4_set_one_direct_mv(s, mx, my, i);
132         return MB_TYPE_DIRECT2 | MB_TYPE_8x8 | MB_TYPE_L0L1;
133     } else if (IS_INTERLACED(colocated_mb_type)) {
134         s->mv_type = MV_TYPE_FIELD;
135         for (i = 0; i < 2; i++) {
136             int field_select = s->next_picture.ref_index[0][4 * mb_index + 2 * i];
137             s->field_select[0][i] = field_select;
138             s->field_select[1][i] = i;
139             if (s->top_field_first) {
140                 time_pp = s->pp_field_time - field_select + i;
141                 time_pb = s->pb_field_time - field_select + i;
142             } else {
143                 time_pp = s->pp_field_time + field_select - i;
144                 time_pb = s->pb_field_time + field_select - i;
145             }
146             s->mv[0][i][0] = s->p_field_mv_table[i][0][mb_index][0] *
147                              time_pb / time_pp + mx;
148             s->mv[0][i][1] = s->p_field_mv_table[i][0][mb_index][1] *
149                              time_pb / time_pp + my;
150             s->mv[1][i][0] = mx ? s->mv[0][i][0] -
151                                   s->p_field_mv_table[i][0][mb_index][0]
152                                 : s->p_field_mv_table[i][0][mb_index][0] *
153                                   (time_pb - time_pp) / time_pp;
154             s->mv[1][i][1] = my ? s->mv[0][i][1] -
155                                   s->p_field_mv_table[i][0][mb_index][1]
156                                 : s->p_field_mv_table[i][0][mb_index][1] *
157                                   (time_pb - time_pp) / time_pp;
158         }
159         return MB_TYPE_DIRECT2 | MB_TYPE_16x8 |
160                MB_TYPE_L0L1    | MB_TYPE_INTERLACED;
161     } else {
162         ff_mpeg4_set_one_direct_mv(s, mx, my, 0);
163         s->mv[0][1][0] =
164         s->mv[0][2][0] =
165         s->mv[0][3][0] = s->mv[0][0][0];
166         s->mv[0][1][1] =
167         s->mv[0][2][1] =
168         s->mv[0][3][1] = s->mv[0][0][1];
169         s->mv[1][1][0] =
170         s->mv[1][2][0] =
171         s->mv[1][3][0] = s->mv[1][0][0];
172         s->mv[1][1][1] =
173         s->mv[1][2][1] =
174         s->mv[1][3][1] = s->mv[1][0][1];
175         if ((s->avctx->workaround_bugs & FF_BUG_DIRECT_BLOCKSIZE) ||
176             !s->quarter_sample)
177             s->mv_type = MV_TYPE_16X16;
178         else
179             s->mv_type = MV_TYPE_8X8;
180         // Note see prev line
181         return MB_TYPE_DIRECT2 | MB_TYPE_16x16 | MB_TYPE_L0L1;
182     }
183 }