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dv.h
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1 /*
2  * Constants for DV codec
3  * Copyright (c) 2002 Fabrice Bellard
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Constants for DV codec.
25  */
26 
27 #ifndef AVCODEC_DV_H
28 #define AVCODEC_DV_H
29 
30 #include "avcodec.h"
31 #include "dv_profile.h"
32 #include "get_bits.h"
33 #include "me_cmp.h"
34 
35 typedef struct DVwork_chunk {
36  uint16_t buf_offset;
37  uint16_t mb_coordinates[5];
38 } DVwork_chunk;
39 
40 typedef struct DVVideoContext {
41  const AVDVProfile *sys;
45 
47 
48  void (*get_pixels)(int16_t *block, const uint8_t *pixels, ptrdiff_t line_size);
49  void (*fdct[2])(int16_t *block);
50  void (*idct_put[2])(uint8_t *dest, int line_size, int16_t *block);
52  DVwork_chunk work_chunks[4 * 12 * 27];
53  uint32_t idct_factor[2 * 4 * 16 * 64];
55 
59  dv_sect_vaux = 0x56,
60  dv_sect_audio = 0x76,
61  dv_sect_video = 0x96,
62 };
63 
65  dv_header525 = 0x3f, /* see dv_write_pack for important details on */
66  dv_header625 = 0xbf, /* these two packs */
67  dv_timecode = 0x13,
77 };
78 
79 #define DV_PROFILE_IS_HD(p) ((p)->video_stype & 0x10)
80 #define DV_PROFILE_IS_1080i50(p) (((p)->video_stype == 0x14) && ((p)->dsf == 1))
81 #define DV_PROFILE_IS_720p50(p) (((p)->video_stype == 0x18) && ((p)->dsf == 1))
82 
83 /**
84  * largest possible DV frame, in bytes (1080i50)
85  */
86 #define DV_MAX_FRAME_SIZE 576000
87 
88 /**
89  * maximum number of blocks per macroblock in any DV format
90  */
91 #define DV_MAX_BPM 8
92 
93 #define TEX_VLC_BITS 10
94 
95 extern RL_VLC_ELEM ff_dv_rl_vlc[1664];
96 
98 
100 
101 static inline int dv_work_pool_size(const AVDVProfile *d)
102 {
103  int size = d->n_difchan * d->difseg_size * 27;
104  if (DV_PROFILE_IS_1080i50(d))
105  size -= 3 * 27;
106  if (DV_PROFILE_IS_720p50(d))
107  size -= 4 * 27;
108  return size;
109 }
110 
111 static inline void dv_calculate_mb_xy(DVVideoContext *s,
112  DVwork_chunk *work_chunk,
113  int m, int *mb_x, int *mb_y)
114 {
115  *mb_x = work_chunk->mb_coordinates[m] & 0xff;
116  *mb_y = work_chunk->mb_coordinates[m] >> 8;
117 
118  /* We work with 720p frames split in half.
119  * The odd half-frame (chan == 2,3) is displaced :-( */
120  if (s->sys->height == 720 && !(s->buf[1] & 0x0C))
121  /* shifting the Y coordinate down by 72/2 macro blocks */
122  *mb_y -= (*mb_y > 17) ? 18 : -72;
123 }
124 
125 #endif /* AVCODEC_DV_H */