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avutil.h
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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  * 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 
47 /**
48  * @defgroup lavu Common utility functions
49  *
50  * @brief
51  * libavutil contains the code shared across all the other FFmpeg
52  * libraries
53  *
54  * @note In order to use the functions provided by avutil you must include
55  * the specific header.
56  *
57  * @{
58  *
59  * @defgroup lavu_crypto Crypto and Hashing
60  *
61  * @{
62  * @}
63  *
64  * @defgroup lavu_math Maths
65  * @{
66  *
67  * @}
68  *
69  * @defgroup lavu_string String Manipulation
70  *
71  * @{
72  *
73  * @}
74  *
75  * @defgroup lavu_mem Memory Management
76  *
77  * @{
78  *
79  * @}
80  *
81  * @defgroup lavu_data Data Structures
82  * @{
83  *
84  * @}
85  *
86  * @defgroup lavu_audio Audio related
87  *
88  * @{
89  *
90  * @}
91  *
92  * @defgroup lavu_error Error Codes
93  *
94  * @{
95  *
96  * @}
97  *
98  * @defgroup lavu_misc Other
99  *
100  * @{
101  *
102  * @defgroup lavu_internal Internal
103  *
104  * Not exported functions, for internal usage only
105  *
106  * @{
107  *
108  * @}
109  */
110 
111 
112 /**
113  * @addtogroup lavu_ver
114  * @{
115  */
116 
117 /**
118  * Return the LIBAVUTIL_VERSION_INT constant.
119  */
120 unsigned avutil_version(void);
121 
122 /**
123  * Return the libavutil build-time configuration.
124  */
125 const char *avutil_configuration(void);
126 
127 /**
128  * Return the libavutil license.
129  */
130 const char *avutil_license(void);
131 
132 /**
133  * @}
134  */
135 
136 /**
137  * @addtogroup lavu_media Media Type
138  * @brief Media Type
139  */
140 
142  AVMEDIA_TYPE_UNKNOWN = -1, ///< Usually treated as AVMEDIA_TYPE_DATA
145  AVMEDIA_TYPE_DATA, ///< Opaque data information usually continuous
147  AVMEDIA_TYPE_ATTACHMENT, ///< Opaque data information usually sparse
149 };
150 
151 /**
152  * Return a string describing the media_type enum, NULL if media_type
153  * is unknown.
154  */
155 const char *av_get_media_type_string(enum AVMediaType media_type);
156 
157 /**
158  * @defgroup lavu_const Constants
159  * @{
160  *
161  * @defgroup lavu_enc Encoding specific
162  *
163  * @note those definition should move to avcodec
164  * @{
165  */
166 
167 #define FF_LAMBDA_SHIFT 7
168 #define FF_LAMBDA_SCALE (1<<FF_LAMBDA_SHIFT)
169 #define FF_QP2LAMBDA 118 ///< factor to convert from H.263 QP to lambda
170 #define FF_LAMBDA_MAX (256*128-1)
171 
172 #define FF_QUALITY_SCALE FF_LAMBDA_SCALE //FIXME maybe remove
173 
174 /**
175  * @}
176  * @defgroup lavu_time Timestamp specific
177  *
178  * FFmpeg internal timebase and timestamp definitions
179  *
180  * @{
181  */
182 
183 /**
184  * @brief Undefined timestamp value
185  *
186  * Usually reported by demuxer that work on containers that do not provide
187  * either pts or dts.
188  */
189 
190 #define AV_NOPTS_VALUE ((int64_t)UINT64_C(0x8000000000000000))
191 
192 /**
193  * Internal time base represented as integer
194  */
195 
196 #define AV_TIME_BASE 1000000
197 
198 /**
199  * Internal time base represented as fractional value
200  */
201 
202 #define AV_TIME_BASE_Q (AVRational){1, AV_TIME_BASE}
203 
204 /**
205  * @}
206  * @}
207  * @defgroup lavu_picture Image related
208  *
209  * AVPicture types, pixel formats and basic image planes manipulation.
210  *
211  * @{
212  */
213 
215  AV_PICTURE_TYPE_NONE = 0, ///< Undefined
216  AV_PICTURE_TYPE_I, ///< Intra
217  AV_PICTURE_TYPE_P, ///< Predicted
218  AV_PICTURE_TYPE_B, ///< Bi-dir predicted
219  AV_PICTURE_TYPE_S, ///< S(GMC)-VOP MPEG4
220  AV_PICTURE_TYPE_SI, ///< Switching Intra
221  AV_PICTURE_TYPE_SP, ///< Switching Predicted
222  AV_PICTURE_TYPE_BI, ///< BI type
223 };
224 
225 /**
226  * Return a single letter to describe the given picture type
227  * pict_type.
228  *
229  * @param[in] pict_type the picture type @return a single character
230  * representing the picture type, '?' if pict_type is unknown
231  */
232 char av_get_picture_type_char(enum AVPictureType pict_type);
233 
234 /**
235  * @}
236  */
237 
238 #include "common.h"
239 #include "error.h"
240 #include "version.h"
241 #include "mathematics.h"
242 #include "rational.h"
243 #include "intfloat_readwrite.h"
244 #include "log.h"
245 #include "pixfmt.h"
246 
247 /**
248  * Return x default pointer in case p is NULL.
249  */
250 static inline void *av_x_if_null(const void *p, const void *x)
251 {
252  return (void *)(intptr_t)(p ? p : x);
253 }
254 
255 /**
256  * @}
257  * @}
258  */
259 
260 #endif /* AVUTIL_AVUTIL_H */