1 /*
2 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #ifndef AVUTIL_AVUTIL_H
22 #define AVUTIL_AVUTIL_H
23
24 /**
25 * @file
26 * external API header
27 */
28
29 /**
30 * @mainpage
31 *
32 * @section ffmpeg_intro Introduction
33 *
34 * This document describes the usage of the different libraries
35 * provided by FFmpeg.
36 *
37 * @li @ref libavc "libavcodec" encoding/decoding library
38 * @li @ref lavfi "libavfilter" graph-based frame editing library
39 * @li @ref libavf "libavformat" I/O and muxing/demuxing library
40 * @li @ref lavd "libavdevice" special devices muxing/demuxing library
41 * @li @ref lavu "libavutil" common utility library
42 * @li @ref lswr "libswresample" audio resampling, format conversion and mixing
43 * @li @ref lpp "libpostproc" post processing library
44 * @li @ref lsws "libswscale" color conversion and scaling library
45 *
46 * @section ffmpeg_versioning Versioning and compatibility
47 *
48 * Each of the FFmpeg libraries contains a version.h header, which defines a
49 * major, minor and micro version number with the
50 * <em>LIBRARYNAME_VERSION_{MAJOR,MINOR,MICRO}</em> macros. The major version
51 * number is incremented with backward incompatible changes - e.g. removing
52 * parts of the public API, reordering public struct members, etc. The minor
53 * version number is incremented for backward compatible API changes or major
54 * new features - e.g. adding a new public function or a new decoder. The micro
55 * version number is incremented for smaller changes that a calling program
56 * might still want to check for - e.g. changing behavior in a previously
57 * unspecified situation.
58 *
59 * FFmpeg guarantees backward API and ABI compatibility for each library as long
60 * as its major version number is unchanged. This means that no public symbols
61 * will be removed or renamed. Types and names of the public struct members and
62 * values of public macros and enums will remain the same (unless they were
63 * explicitly declared as not part of the public API). Documented behavior will
64 * not change.
65 *
66 * In other words, any correct program that works with a given FFmpeg snapshot
67 * should work just as well without any changes with any later snapshot with the
68 * same major versions. This applies to both rebuilding the program against new
69 * FFmpeg versions or to replacing the dynamic FFmpeg libraries that a program
70 * links against.
71 *
72 * However, new public symbols may be added and new members may be appended to
73 * public structs whose size is not part of public ABI (most public structs in
74 * FFmpeg). New macros and enum values may be added. Behavior in undocumented
75 * situations may change slightly (and be documented). All those are accompanied
76 * by an entry in doc/APIchanges and incrementing either the minor or micro
77 * version number.
78 */
79
80 /**
81 * @defgroup lavu Common utility functions
82 *
83 * @brief
84 * libavutil contains the code shared across all the other FFmpeg
85 * libraries
86 *
87 * @note In order to use the functions provided by avutil you must include
88 * the specific header.
89 *
90 * @{
91 *
92 * @defgroup lavu_crypto Crypto and Hashing
93 *
94 * @{
95 * @}
96 *
97 * @defgroup lavu_math Maths
98 * @{
99 *
100 * @}
101 *
102 * @defgroup lavu_string String Manipulation
103 *
104 * @{
105 *
106 * @}
107 *
108 * @defgroup lavu_mem Memory Management
109 *
110 * @{
111 *
112 * @}
113 *
114 * @defgroup lavu_data Data Structures
115 * @{
116 *
117 * @}
118 *
119 * @defgroup lavu_audio Audio related
120 *
121 * @{
122 *
123 * @}
124 *
125 * @defgroup lavu_error Error Codes
126 *
127 * @{
128 *
129 * @}
130 *
131 * @defgroup lavu_log Logging Facility
132 *
133 * @{
134 *
135 * @}
136 *
137 * @defgroup lavu_misc Other
138 *
139 * @{
140 *
141 * @defgroup lavu_internal Internal
142 *
143 * Not exported functions, for internal usage only
144 *
145 * @{
146 *
147 * @}
148 */
149
150
151 /**
152 * @addtogroup lavu_ver
153 * @{
154 */
155
156 /**
157 * Return the LIBAVUTIL_VERSION_INT constant.
158 */
160
161 /**
162 * Return the libavutil build-time configuration.
163 */
165
166 /**
167 * Return the libavutil license.
168 */
170
171 /**
172 * @}
173 */
174
175 /**
176 * @addtogroup lavu_media Media Type
177 * @brief Media Type
178 */
179
188 };
189
190 /**
191 * Return a string describing the media_type enum, NULL if media_type
192 * is unknown.
193 */
195
196 /**
197 * @defgroup lavu_const Constants
198 * @{
199 *
200 * @defgroup lavu_enc Encoding specific
201 *
202 * @note those definition should move to avcodec
203 * @{
204 */
205
206 #define FF_LAMBDA_SHIFT 7
207 #define FF_LAMBDA_SCALE (1<<FF_LAMBDA_SHIFT)
208 #define FF_QP2LAMBDA 118 ///< factor to convert from H.263 QP to lambda
209 #define FF_LAMBDA_MAX (256*128-1)
210
211 #define FF_QUALITY_SCALE FF_LAMBDA_SCALE //FIXME maybe remove
212
213 /**
214 * @}
215 * @defgroup lavu_time Timestamp specific
216 *
217 * FFmpeg internal timebase and timestamp definitions
218 *
219 * @{
220 */
221
222 /**
223 * @brief Undefined timestamp value
224 *
225 * Usually reported by demuxer that work on containers that do not provide
226 * either pts or dts.
227 */
228
229 #define AV_NOPTS_VALUE ((int64_t)UINT64_C(0x8000000000000000))
230
231 /**
232 * Internal time base represented as integer
233 */
234
235 #define AV_TIME_BASE 1000000
236
237 /**
238 * Internal time base represented as fractional value
239 */
240
241 #define AV_TIME_BASE_Q (AVRational){1, AV_TIME_BASE}
242
243 /**
244 * @}
245 * @}
246 * @defgroup lavu_picture Image related
247 *
248 * AVPicture types, pixel formats and basic image planes manipulation.
249 *
250 * @{
251 */
252
262 };
263
264 /**
265 * Return a single letter to describe the given picture type
266 * pict_type.
267 *
268 * @param[in] pict_type the picture type @return a single character
269 * representing the picture type, '?' if pict_type is unknown
270 */
272
273 /**
274 * @}
275 */
276
285
286 /**
287 * Return x default pointer in case p is NULL.
288 */
290 {
291 return (void *)(intptr_t)(p ? p : x);
292 }
293
294 /**
295 * Compute the length of an integer list.
296 *
297 * @param elsize size in bytes of each list element (only 1, 2, 4 or 8)
298 * @param term list terminator (usually 0 or -1)
299 * @param list pointer to the list
300 * @return length of the list, in elements, not counting the terminator
301 */
303 const void *list, uint64_t term)
av_pure;
304
305 /**
306 * Compute the length of an integer list.
307 *
308 * @param term list terminator (usually 0 or -1)
309 * @param list pointer to the list
310 * @return length of the list, in elements, not counting the terminator
311 */
312 #define av_int_list_length(list, term) \
313 av_int_list_length_for_size(sizeof(*(list)), list, term)
314
315 /**
316 * @}
317 * @}
318 */
319
320 #endif /* AVUTIL_AVUTIL_H */