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;
42     AVFrame         *frame;
43     AVCodecContext  *avctx;
44     uint8_t         *buf;
45 
46     uint8_t dv_zigzag[2][64];
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);
51     me_cmp_func ildct_cmp;
52     DVwork_chunk work_chunks[4 * 12 * 27];
53     uint32_t idct_factor[2 * 4 * 16 * 64];
54 } DVVideoContext;
55 
56 enum dv_section_type {
57     dv_sect_header  = 0x1f,
58     dv_sect_subcode = 0x3f,
59     dv_sect_vaux    = 0x56,
60     dv_sect_audio   = 0x76,
61     dv_sect_video   = 0x96,
62 };
63 
64 enum dv_pack_type {
65     dv_header525     = 0x3f,  /* see dv_write_pack for important details on */
66     dv_header625     = 0xbf,  /* these two packs */
67     dv_timecode      = 0x13,
68     dv_audio_source  = 0x50,
69     dv_audio_control = 0x51,
70     dv_audio_recdate = 0x52,
71     dv_audio_rectime = 0x53,
72     dv_video_source  = 0x60,
73     dv_video_control = 0x61,
74     dv_video_recdate = 0x62,
75     dv_video_rectime = 0x63,
76     dv_unknown_pack  = 0xff,
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 9
94 
95 extern RL_VLC_ELEM ff_dv_rl_vlc[1184];
96 
97 int ff_dv_init_dynamic_tables(DVVideoContext *s, const AVDVProfile *d);
98 int ff_dvvideo_init(AVCodecContext *avctx);
99 
dv_work_pool_size(const AVDVProfile * d)100 static inline int dv_work_pool_size(const AVDVProfile *d)
101 {
102     int size = d->n_difchan * d->difseg_size * 27;
103     if (DV_PROFILE_IS_1080i50(d))
104         size -= 3 * 27;
105     if (DV_PROFILE_IS_720p50(d))
106         size -= 4 * 27;
107     return size;
108 }
109 
dv_calculate_mb_xy(DVVideoContext * s,DVwork_chunk * work_chunk,int m,int * mb_x,int * mb_y)110 static inline void dv_calculate_mb_xy(DVVideoContext *s,
111                                       DVwork_chunk *work_chunk,
112                                       int m, int *mb_x, int *mb_y)
113 {
114     *mb_x = work_chunk->mb_coordinates[m] & 0xff;
115     *mb_y = work_chunk->mb_coordinates[m] >> 8;
116 
117     /* We work with 720p frames split in half.
118      * The odd half-frame (chan == 2,3) is displaced :-( */
119     if (s->sys->height == 720 && !(s->buf[1] & 0x0C))
120         /* shifting the Y coordinate down by 72/2 macro blocks */
121         *mb_y -= (*mb_y > 17) ? 18 : -72;
122 }
123 
124 #endif /* AVCODEC_DV_H */
125