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[libav.git] / cmdutils.h
1 /*
2 * Various utilities for command line tools
3 * copyright (c) 2003 Fabrice Bellard
4 *
5 * This file is part of Libav.
6 *
7 * Libav 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 * Libav 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 Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #ifndef LIBAV_CMDUTILS_H
23 #define LIBAV_CMDUTILS_H
24
25 #include <stdint.h>
26
27 #include "libavcodec/avcodec.h"
28 #include "libavfilter/avfilter.h"
29 #include "libavformat/avformat.h"
30 #include "libswscale/swscale.h"
31
32 /**
33 * program name, defined by the program for show_version().
34 */
35 extern const char program_name[];
36
37 /**
38 * program birth year, defined by the program for show_banner()
39 */
40 extern const int program_birth_year;
41
42 extern AVCodecContext *avcodec_opts[AVMEDIA_TYPE_NB];
43 extern AVFormatContext *avformat_opts;
44 extern struct SwsContext *sws_opts;
45 extern AVDictionary *format_opts, *codec_opts;
46
47 /**
48 * Initialize the cmdutils option system, in particular
49 * allocate the *_opts contexts.
50 */
51 void init_opts(void);
52 /**
53 * Uninitialize the cmdutils option system, in particular
54 * free the *_opts contexts and their contents.
55 */
56 void uninit_opts(void);
57
58 /**
59 * Trivial log callback.
60 * Only suitable for show_help and similar since it lacks prefix handling.
61 */
62 void log_callback_help(void* ptr, int level, const char* fmt, va_list vl);
63
64 /**
65 * Fallback for options that are not explicitly handled, these will be
66 * parsed through AVOptions.
67 */
68 int opt_default(const char *opt, const char *arg);
69
70 /**
71 * Set the libav* libraries log level.
72 */
73 int opt_loglevel(const char *opt, const char *arg);
74
75 /**
76 * Limit the execution time.
77 */
78 int opt_timelimit(const char *opt, const char *arg);
79
80 /**
81 * Parse a string and return its corresponding value as a double.
82 * Exit from the application if the string cannot be correctly
83 * parsed or the corresponding value is invalid.
84 *
85 * @param context the context of the value to be set (e.g. the
86 * corresponding commandline option name)
87 * @param numstr the string to be parsed
88 * @param type the type (OPT_INT64 or OPT_FLOAT) as which the
89 * string should be parsed
90 * @param min the minimum valid accepted value
91 * @param max the maximum valid accepted value
92 */
93 double parse_number_or_die(const char *context, const char *numstr, int type, double min, double max);
94
95 /**
96 * Parse a string specifying a time and return its corresponding
97 * value as a number of microseconds. Exit from the application if
98 * the string cannot be correctly parsed.
99 *
100 * @param context the context of the value to be set (e.g. the
101 * corresponding commandline option name)
102 * @param timestr the string to be parsed
103 * @param is_duration a flag which tells how to interpret timestr, if
104 * not zero timestr is interpreted as a duration, otherwise as a
105 * date
106 *
107 * @see parse_date()
108 */
109 int64_t parse_time_or_die(const char *context, const char *timestr, int is_duration);
110
111 typedef struct SpecifierOpt {
112 char *specifier; /**< stream/chapter/program/... specifier */
113 union {
114 uint8_t *str;
115 int i;
116 int64_t i64;
117 float f;
118 double dbl;
119 } u;
120 } SpecifierOpt;
121
122 typedef struct {
123 const char *name;
124 int flags;
125 #define HAS_ARG 0x0001
126 #define OPT_BOOL 0x0002
127 #define OPT_EXPERT 0x0004
128 #define OPT_STRING 0x0008
129 #define OPT_VIDEO 0x0010
130 #define OPT_AUDIO 0x0020
131 #define OPT_GRAB 0x0040
132 #define OPT_INT 0x0080
133 #define OPT_FLOAT 0x0100
134 #define OPT_SUBTITLE 0x0200
135 #define OPT_INT64 0x0400
136 #define OPT_EXIT 0x0800
137 #define OPT_DATA 0x1000
138 #define OPT_FUNC2 0x2000
139 #define OPT_OFFSET 0x4000 /* option is specified as an offset in a passed optctx */
140 #define OPT_SPEC 0x8000 /* option is to be stored in an array of SpecifierOpt.
141 Implies OPT_OFFSET. Next element after the offset is
142 an int containing element count in the array. */
143 #define OPT_TIME 0x10000
144 #define OPT_DOUBLE 0x20000
145 union {
146 void *dst_ptr;
147 int (*func_arg)(const char *, const char *);
148 int (*func2_arg)(void *, const char *, const char *);
149 size_t off;
150 } u;
151 const char *help;
152 const char *argname;
153 } OptionDef;
154
155 void show_help_options(const OptionDef *options, const char *msg, int mask, int value);
156
157 /**
158 * Show help for all options with given flags in class and all its
159 * children.
160 */
161 void show_help_children(const AVClass *class, int flags);
162
163 /**
164 * Parse the command line arguments.
165 *
166 * @param optctx an opaque options context
167 * @param options Array with the definitions required to interpret every
168 * option of the form: -option_name [argument]
169 * @param parse_arg_function Name of the function called to process every
170 * argument without a leading option name flag. NULL if such arguments do
171 * not have to be processed.
172 */
173 void parse_options(void *optctx, int argc, char **argv, const OptionDef *options,
174 void (* parse_arg_function)(void *optctx, const char*));
175
176 /**
177 * Parse one given option.
178 *
179 * @return on success 1 if arg was consumed, 0 otherwise; negative number on error
180 */
181 int parse_option(void *optctx, const char *opt, const char *arg, const OptionDef *options);
182
183 /**
184 * Find the '-loglevel' option in the commandline args and apply it.
185 */
186 void parse_loglevel(int argc, char **argv, const OptionDef *options);
187
188 /**
189 * Check if the given stream matches a stream specifier.
190 *
191 * @param s Corresponding format context.
192 * @param st Stream from s to be checked.
193 * @param spec A stream specifier of the [v|a|s|d]:[\<stream index\>] form.
194 *
195 * @return 1 if the stream matches, 0 if it doesn't, <0 on error
196 */
197 int check_stream_specifier(AVFormatContext *s, AVStream *st, const char *spec);
198
199 /**
200 * Filter out options for given codec.
201 *
202 * Create a new options dictionary containing only the options from
203 * opts which apply to the codec with ID codec_id.
204 *
205 * @param s Corresponding format context.
206 * @param st A stream from s for which the options should be filtered.
207 * @return a pointer to the created dictionary
208 */
209 AVDictionary *filter_codec_opts(AVDictionary *opts, enum CodecID codec_id, AVFormatContext *s, AVStream *st);
210
211 /**
212 * Setup AVCodecContext options for avformat_find_stream_info().
213 *
214 * Create an array of dictionaries, one dictionary for each stream
215 * contained in s.
216 * Each dictionary will contain the options from codec_opts which can
217 * be applied to the corresponding stream codec context.
218 *
219 * @return pointer to the created array of dictionaries, NULL if it
220 * cannot be created
221 */
222 AVDictionary **setup_find_stream_info_opts(AVFormatContext *s, AVDictionary *codec_opts);
223
224 /**
225 * Print an error message to stderr, indicating filename and a human
226 * readable description of the error code err.
227 *
228 * If strerror_r() is not available the use of this function in a
229 * multithreaded application may be unsafe.
230 *
231 * @see av_strerror()
232 */
233 void print_error(const char *filename, int err);
234
235 /**
236 * Print the program banner to stderr. The banner contents depend on the
237 * current version of the repository and of the libav* libraries used by
238 * the program.
239 */
240 void show_banner(void);
241
242 /**
243 * Print the version of the program to stdout. The version message
244 * depends on the current versions of the repository and of the libav*
245 * libraries.
246 */
247 void show_version(void);
248
249 /**
250 * Print the license of the program to stdout. The license depends on
251 * the license of the libraries compiled into the program.
252 */
253 void show_license(void);
254
255 /**
256 * Print a listing containing all the formats supported by the
257 * program.
258 */
259 void show_formats(void);
260
261 /**
262 * Print a listing containing all the codecs supported by the
263 * program.
264 */
265 void show_codecs(void);
266
267 /**
268 * Print a listing containing all the filters supported by the
269 * program.
270 */
271 void show_filters(void);
272
273 /**
274 * Print a listing containing all the bit stream filters supported by the
275 * program.
276 */
277 void show_bsfs(void);
278
279 /**
280 * Print a listing containing all the protocols supported by the
281 * program.
282 */
283 void show_protocols(void);
284
285 /**
286 * Print a listing containing all the pixel formats supported by the
287 * program.
288 */
289 void show_pix_fmts(void);
290
291 /**
292 * Print a listing containing all the sample formats supported by the
293 * program.
294 */
295 int show_sample_fmts(const char *opt, const char *arg);
296
297 /**
298 * Return a positive value if a line read from standard input
299 * starts with [yY], otherwise return 0.
300 */
301 int read_yesno(void);
302
303 /**
304 * Read the file with name filename, and put its content in a newly
305 * allocated 0-terminated buffer.
306 *
307 * @param bufptr location where pointer to buffer is returned
308 * @param size location where size of buffer is returned
309 * @return 0 in case of success, a negative value corresponding to an
310 * AVERROR error code in case of failure.
311 */
312 int cmdutils_read_file(const char *filename, char **bufptr, size_t *size);
313
314 typedef struct {
315 int64_t num_faulty_pts; /// Number of incorrect PTS values so far
316 int64_t num_faulty_dts; /// Number of incorrect DTS values so far
317 int64_t last_pts; /// PTS of the last frame
318 int64_t last_dts; /// DTS of the last frame
319 } PtsCorrectionContext;
320
321 /**
322 * Reset the state of the PtsCorrectionContext.
323 */
324 void init_pts_correction(PtsCorrectionContext *ctx);
325
326 /**
327 * Attempt to guess proper monotonic timestamps for decoded video frames
328 * which might have incorrect times. Input timestamps may wrap around, in
329 * which case the output will as well.
330 *
331 * @param pts the pts field of the decoded AVPacket, as passed through
332 * AVCodecContext.reordered_opaque
333 * @param dts the dts field of the decoded AVPacket
334 * @return one of the input values, may be AV_NOPTS_VALUE
335 */
336 int64_t guess_correct_pts(PtsCorrectionContext *ctx, int64_t pts, int64_t dts);
337
338 /**
339 * Get a file corresponding to a preset file.
340 *
341 * If is_path is non-zero, look for the file in the path preset_name.
342 * Otherwise search for a file named arg.ffpreset in the directories
343 * $AVCONV_DATADIR (if set), $HOME/.avconv, and in the datadir defined
344 * at configuration time, in that order. If no such file is found and
345 * codec_name is defined, then search for a file named
346 * codec_name-preset_name.ffpreset in the above-mentioned directories.
347 *
348 * @param filename buffer where the name of the found filename is written
349 * @param filename_size size in bytes of the filename buffer
350 * @param preset_name name of the preset to search
351 * @param is_path tell if preset_name is a filename path
352 * @param codec_name name of the codec for which to look for the
353 * preset, may be NULL
354 */
355 FILE *get_preset_file(char *filename, size_t filename_size,
356 const char *preset_name, int is_path, const char *codec_name);
357
358 typedef struct {
359 enum PixelFormat pix_fmt;
360 } FFSinkContext;
361
362 extern AVFilter ffsink;
363
364 /**
365 * Extract a frame from sink.
366 *
367 * @return a negative error in case of failure, 1 if one frame has
368 * been extracted successfully.
369 */
370 int get_filtered_video_frame(AVFilterContext *sink, AVFrame *frame,
371 AVFilterBufferRef **picref, AVRational *pts_tb);
372
373 /**
374 * Do all the necessary cleanup and abort.
375 * This function is implemented in the avtools, not cmdutils.
376 */
377 void exit_program(int ret);
378
379 /**
380 * Realloc array to hold new_size elements of elem_size.
381 * Calls exit_program() on failure.
382 *
383 * @param elem_size size in bytes of each element
384 * @param size new element count will be written here
385 * @return reallocated array
386 */
387 void *grow_array(void *array, int elem_size, int *size, int new_size);
388
389 #endif /* LIBAV_CMDUTILS_H */