1 /*
2  *
3  * This file is part of FFmpeg.
4  *
5  * FFmpeg is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Lesser General Public
7  * License as published by the Free Software Foundation; either
8  * version 2.1 of the License, or (at your option) any later version.
9  *
10  * FFmpeg is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * Lesser General Public License for more details.
14  *
15  * You should have received a copy of the GNU Lesser General Public
16  * License along with FFmpeg; if not, write to the Free Software
17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18  */
19 
20 #ifndef AVCODEC_DEFS_H
21 #define AVCODEC_DEFS_H
22 
23 /**
24  * @file
25  * @ingroup libavc
26  * Misc types and constants that do not belong anywhere else.
27  */
28 
29 #include <stdint.h>
30 #include <stdlib.h>
31 
32 /**
33  * @ingroup lavc_decoding
34  * Required number of additionally allocated bytes at the end of the input bitstream for decoding.
35  * This is mainly needed because some optimized bitstream readers read
36  * 32 or 64 bit at once and could read over the end.<br>
37  * Note: If the first 23 bits of the additional bytes are not 0, then damaged
38  * MPEG bitstreams could cause overread and segfault.
39  */
40 #define AV_INPUT_BUFFER_PADDING_SIZE 64
41 
42 /**
43  * @ingroup lavc_decoding
44  */
45 enum AVDiscard{
46     /* We leave some space between them for extensions (drop some
47      * keyframes for intra-only or drop just some bidir frames). */
48     AVDISCARD_NONE    =-16, ///< discard nothing
49     AVDISCARD_DEFAULT =  0, ///< discard useless packets like 0 size packets in avi
50     AVDISCARD_NONREF  =  8, ///< discard all non reference
51     AVDISCARD_BIDIR   = 16, ///< discard all bidirectional frames
52     AVDISCARD_NONINTRA= 24, ///< discard all non intra frames
53     AVDISCARD_NONKEY  = 32, ///< discard all frames except keyframes
54     AVDISCARD_ALL     = 48, ///< discard all
55 };
56 
57 enum AVAudioServiceType {
58     AV_AUDIO_SERVICE_TYPE_MAIN              = 0,
59     AV_AUDIO_SERVICE_TYPE_EFFECTS           = 1,
60     AV_AUDIO_SERVICE_TYPE_VISUALLY_IMPAIRED = 2,
61     AV_AUDIO_SERVICE_TYPE_HEARING_IMPAIRED  = 3,
62     AV_AUDIO_SERVICE_TYPE_DIALOGUE          = 4,
63     AV_AUDIO_SERVICE_TYPE_COMMENTARY        = 5,
64     AV_AUDIO_SERVICE_TYPE_EMERGENCY         = 6,
65     AV_AUDIO_SERVICE_TYPE_VOICE_OVER        = 7,
66     AV_AUDIO_SERVICE_TYPE_KARAOKE           = 8,
67     AV_AUDIO_SERVICE_TYPE_NB                   , ///< Not part of ABI
68 };
69 
70 /**
71  * Pan Scan area.
72  * This specifies the area which should be displayed.
73  * Note there may be multiple such areas for one frame.
74  */
75 typedef struct AVPanScan {
76     /**
77      * id
78      * - encoding: Set by user.
79      * - decoding: Set by libavcodec.
80      */
81     int id;
82 
83     /**
84      * width and height in 1/16 pel
85      * - encoding: Set by user.
86      * - decoding: Set by libavcodec.
87      */
88     int width;
89     int height;
90 
91     /**
92      * position of the top left corner in 1/16 pel for up to 3 fields/frames
93      * - encoding: Set by user.
94      * - decoding: Set by libavcodec.
95      */
96     int16_t position[3][2];
97 } AVPanScan;
98 
99 /**
100  * This structure describes the bitrate properties of an encoded bitstream. It
101  * roughly corresponds to a subset the VBV parameters for MPEG-2 or HRD
102  * parameters for H.264/HEVC.
103  */
104 typedef struct AVCPBProperties {
105     /**
106      * Maximum bitrate of the stream, in bits per second.
107      * Zero if unknown or unspecified.
108      */
109     int64_t max_bitrate;
110     /**
111      * Minimum bitrate of the stream, in bits per second.
112      * Zero if unknown or unspecified.
113      */
114     int64_t min_bitrate;
115     /**
116      * Average bitrate of the stream, in bits per second.
117      * Zero if unknown or unspecified.
118      */
119     int64_t avg_bitrate;
120 
121     /**
122      * The size of the buffer to which the ratecontrol is applied, in bits.
123      * Zero if unknown or unspecified.
124      */
125     int64_t buffer_size;
126 
127     /**
128      * The delay between the time the packet this structure is associated with
129      * is received and the time when it should be decoded, in periods of a 27MHz
130      * clock.
131      *
132      * UINT64_MAX when unknown or unspecified.
133      */
134     uint64_t vbv_delay;
135 } AVCPBProperties;
136 
137 /**
138  * Allocate a CPB properties structure and initialize its fields to default
139  * values.
140  *
141  * @param size if non-NULL, the size of the allocated struct will be written
142  *             here. This is useful for embedding it in side data.
143  *
144  * @return the newly allocated struct or NULL on failure
145  */
146 AVCPBProperties *av_cpb_properties_alloc(size_t *size);
147 
148 /**
149  * This structure supplies correlation between a packet timestamp and a wall clock
150  * production time. The definition follows the Producer Reference Time ('prft')
151  * as defined in ISO/IEC 14496-12
152  */
153 typedef struct AVProducerReferenceTime {
154     /**
155      * A UTC timestamp, in microseconds, since Unix epoch (e.g, av_gettime()).
156      */
157     int64_t wallclock;
158     int flags;
159 } AVProducerReferenceTime;
160 
161 /**
162  * Encode extradata length to a buffer. Used by xiph codecs.
163  *
164  * @param s buffer to write to; must be at least (v/255+1) bytes long
165  * @param v size of extradata in bytes
166  * @return number of bytes written to the buffer.
167  */
168 unsigned int av_xiphlacing(unsigned char *s, unsigned int v);
169 
170 #endif // AVCODEC_DEFS_H
171