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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 * @ingroup lavu
27 * Convenience header that includes @ref lavu "libavutil"'s core.
28 */
29
30/**
31 * @mainpage
32 *
33 * @section ffmpeg_intro Introduction
34 *
35 * This document describes the usage of the different libraries
36 * provided by FFmpeg.
37 *
38 * @li @ref libavc "libavcodec" encoding/decoding library
39 * @li @ref lavfi "libavfilter" graph-based frame editing library
40 * @li @ref libavf "libavformat" I/O and muxing/demuxing library
41 * @li @ref lavd "libavdevice" special devices muxing/demuxing library
42 * @li @ref lavu "libavutil" common utility library
43 * @li @ref lswr "libswresample" audio resampling, format conversion and mixing
44 * @li @ref lpp "libpostproc" post processing library
45 * @li @ref libsws "libswscale" color conversion and scaling library
46 *
47 * @section ffmpeg_versioning Versioning and compatibility
48 *
49 * Each of the FFmpeg libraries contains a version.h header, which defines a
50 * major, minor and micro version number with the
51 * <em>LIBRARYNAME_VERSION_{MAJOR,MINOR,MICRO}</em> macros. The major version
52 * number is incremented with backward incompatible changes - e.g. removing
53 * parts of the public API, reordering public struct members, etc. The minor
54 * version number is incremented for backward compatible API changes or major
55 * new features - e.g. adding a new public function or a new decoder. The micro
56 * version number is incremented for smaller changes that a calling program
57 * might still want to check for - e.g. changing behavior in a previously
58 * unspecified situation.
59 *
60 * FFmpeg guarantees backward API and ABI compatibility for each library as long
61 * as its major version number is unchanged. This means that no public symbols
62 * will be removed or renamed. Types and names of the public struct members and
63 * values of public macros and enums will remain the same (unless they were
64 * explicitly declared as not part of the public API). Documented behavior will
65 * not change.
66 *
67 * In other words, any correct program that works with a given FFmpeg snapshot
68 * should work just as well without any changes with any later snapshot with the
69 * same major versions. This applies to both rebuilding the program against new
70 * FFmpeg versions or to replacing the dynamic FFmpeg libraries that a program
71 * links against.
72 *
73 * However, new public symbols may be added and new members may be appended to
74 * public structs whose size is not part of public ABI (most public structs in
75 * FFmpeg). New macros and enum values may be added. Behavior in undocumented
76 * situations may change slightly (and be documented). All those are accompanied
77 * by an entry in doc/APIchanges and incrementing either the minor or micro
78 * version number.
79 */
80
81/**
82 * @defgroup lavu libavutil
83 * Common code shared across all FFmpeg libraries.
84 *
85 * @note
86 * libavutil is designed to be modular. In most cases, in order to use the
87 * functions provided by one component of libavutil you must explicitly include
88 * the specific header containing that feature. If you are only using
89 * media-related components, you could simply include libavutil/avutil.h, which
90 * brings in most of the "core" components.
91 *
92 * @{
93 *
94 * @defgroup lavu_crypto Crypto and Hashing
95 *
96 * @{
97 * @}
98 *
99 * @defgroup lavu_math Mathematics
100 * @{
101 *
102 * @}
103 *
104 * @defgroup lavu_string String Manipulation
105 *
106 * @{
107 *
108 * @}
109 *
110 * @defgroup lavu_mem Memory Management
111 *
112 * @{
113 *
114 * @}
115 *
116 * @defgroup lavu_data Data Structures
117 * @{
118 *
119 * @}
120 *
121 * @defgroup lavu_video Video related
122 *
123 * @{
124 *
125 * @}
126 *
127 * @defgroup lavu_audio Audio related
128 *
129 * @{
130 *
131 * @}
132 *
133 * @defgroup lavu_error Error Codes
134 *
135 * @{
136 *
137 * @}
138 *
139 * @defgroup lavu_log Logging Facility
140 *
141 * @{
142 *
143 * @}
144 *
145 * @defgroup lavu_misc Other
146 *
147 * @{
148 *
149 * @defgroup preproc_misc Preprocessor String Macros
150 *
151 * @{
152 *
153 * @}
154 *
155 * @defgroup version_utils Library Version Macros
156 *
157 * @{
158 *
159 * @}
160 */
161
162
163/**
164 * @addtogroup lavu_ver
165 * @{
166 */
167
168/**
169 * Return the LIBAVUTIL_VERSION_INT constant.
170 */
171unsigned avutil_version(void);
172
173/**
174 * Return an informative version string. This usually is the actual release
175 * version number or a git commit description. This string has no fixed format
176 * and can change any time. It should never be parsed by code.
177 */
178const char *av_version_info(void);
179
180/**
181 * Return the libavutil build-time configuration.
182 */
183const char *avutil_configuration(void);
184
185/**
186 * Return the libavutil license.
187 */
188const char *avutil_license(void);
189
190/**
191 * @}
192 */
193
194/**
195 * @addtogroup lavu_media Media Type
196 * @brief Media Type
197 */
198
199enum AVMediaType {
200 AVMEDIA_TYPE_UNKNOWN = -1, ///< Usually treated as AVMEDIA_TYPE_DATA
201 AVMEDIA_TYPE_VIDEO,
202 AVMEDIA_TYPE_AUDIO,
203 AVMEDIA_TYPE_DATA, ///< Opaque data information usually continuous
204 AVMEDIA_TYPE_SUBTITLE,
205 AVMEDIA_TYPE_ATTACHMENT, ///< Opaque data information usually sparse
206 AVMEDIA_TYPE_NB
207};
208
209/**
210 * Return a string describing the media_type enum, NULL if media_type
211 * is unknown.
212 */
213const char *av_get_media_type_string(enum AVMediaType media_type);
214
215/**
216 * @defgroup lavu_const Constants
217 * @{
218 *
219 * @defgroup lavu_enc Encoding specific
220 *
221 * @note those definition should move to avcodec
222 * @{
223 */
224
225#define FF_LAMBDA_SHIFT 7
226#define FF_LAMBDA_SCALE (1<<FF_LAMBDA_SHIFT)
227#define FF_QP2LAMBDA 118 ///< factor to convert from H.263 QP to lambda
228#define FF_LAMBDA_MAX (256*128-1)
229
230#define FF_QUALITY_SCALE FF_LAMBDA_SCALE //FIXME maybe remove
231
232/**
233 * @}
234 * @defgroup lavu_time Timestamp specific
235 *
236 * FFmpeg internal timebase and timestamp definitions
237 *
238 * @{
239 */
240
241/**
242 * @brief Undefined timestamp value
243 *
244 * Usually reported by demuxer that work on containers that do not provide
245 * either pts or dts.
246 */
247
248#define AV_NOPTS_VALUE ((int64_t)UINT64_C(0x8000000000000000))
249
250/**
251 * Internal time base represented as integer
252 */
253
254#define AV_TIME_BASE 1000000
255
256/**
257 * Internal time base represented as fractional value
258 */
259
260#define AV_TIME_BASE_Q (AVRational){1, AV_TIME_BASE}
261
262/**
263 * @}
264 * @}
265 * @defgroup lavu_picture Image related
266 *
267 * AVPicture types, pixel formats and basic image planes manipulation.
268 *
269 * @{
270 */
271
272enum AVPictureType {
273 AV_PICTURE_TYPE_NONE = 0, ///< Undefined
274 AV_PICTURE_TYPE_I, ///< Intra
275 AV_PICTURE_TYPE_P, ///< Predicted
276 AV_PICTURE_TYPE_B, ///< Bi-dir predicted
277 AV_PICTURE_TYPE_S, ///< S(GMC)-VOP MPEG-4
278 AV_PICTURE_TYPE_SI, ///< Switching Intra
279 AV_PICTURE_TYPE_SP, ///< Switching Predicted
280 AV_PICTURE_TYPE_BI, ///< BI type
281};
282
283/**
284 * Return a single letter to describe the given picture type
285 * pict_type.
286 *
287 * @param[in] pict_type the picture type @return a single character
288 * representing the picture type, '?' if pict_type is unknown
289 */
290char av_get_picture_type_char(enum AVPictureType pict_type);
291
292/**
293 * @}
294 */
295
296#include "common.h"
297#include "error.h"
298#include "rational.h"
299#include "version.h"
300#include "macros.h"
301#include "mathematics.h"
302#include "log.h"
303#include "pixfmt.h"
304
305/**
306 * Return x default pointer in case p is NULL.
307 */
308static inline void *av_x_if_null(const void *p, const void *x)
309{
310 return (void *)(intptr_t)(p ? p : x);
311}
312
313/**
314 * Compute the length of an integer list.
315 *
316 * @param elsize size in bytes of each list element (only 1, 2, 4 or 8)
317 * @param term list terminator (usually 0 or -1)
318 * @param list pointer to the list
319 * @return length of the list, in elements, not counting the terminator
320 */
321unsigned av_int_list_length_for_size(unsigned elsize,
322 const void *list, uint64_t term) av_pure;
323
324/**
325 * Compute the length of an integer list.
326 *
327 * @param term list terminator (usually 0 or -1)
328 * @param list pointer to the list
329 * @return length of the list, in elements, not counting the terminator
330 */
331#define av_int_list_length(list, term) \
332 av_int_list_length_for_size(sizeof(*(list)), list, term)
333
334/**
335 * Open a file using a UTF-8 filename.
336 * The API of this function matches POSIX fopen(), errors are returned through
337 * errno.
338 */
339FILE *av_fopen_utf8(const char *path, const char *mode);
340
341/**
342 * Return the fractional representation of the internal time base.
343 */
344AVRational av_get_time_base_q(void);
345
346#define AV_FOURCC_MAX_STRING_SIZE 32
347
348#define av_fourcc2str(fourcc) av_fourcc_make_string((char[AV_FOURCC_MAX_STRING_SIZE]){0}, fourcc)
349
350/**
351 * Fill the provided buffer with a string containing a FourCC (four-character
352 * code) representation.
353 *
354 * @param buf a buffer with size in bytes of at least AV_FOURCC_MAX_STRING_SIZE
355 * @param fourcc the fourcc to represent
356 * @return the buffer in input
357 */
358char *av_fourcc_make_string(char *buf, uint32_t fourcc);
359
360/**
361 * @}
362 * @}
363 */
364
365#endif /* AVUTIL_AVUTIL_H */
366
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