FFmpeg 5.1.6
metadata.c
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1/*
2 * Copyright (c) 2011 Reinhard Tartler
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a copy
5 * of this software and associated documentation files (the "Software"), to deal
6 * in the Software without restriction, including without limitation the rights
7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8 * copies of the Software, and to permit persons to whom the Software is
9 * furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
20 * THE SOFTWARE.
21 */
22
23/**
24 * @file
25 * Shows how the metadata API can be used in application programs.
26 * @example metadata.c
27 */
28
29#include <stdio.h>
30
32#include <libavutil/dict.h>
33
34int main (int argc, char **argv)
35{
37 const AVDictionaryEntry *tag = NULL;
38 int ret;
39
40 if (argc != 2) {
41 printf("usage: %s <input_file>\n"
42 "example program to demonstrate the use of the libavformat metadata API.\n"
43 "\n", argv[0]);
44 return 1;
45 }
46
47 if ((ret = avformat_open_input(&fmt_ctx, argv[1], NULL, NULL)))
48 return ret;
49
50 if ((ret = avformat_find_stream_info(fmt_ctx, NULL)) < 0) {
51 av_log(NULL, AV_LOG_ERROR, "Cannot find stream information\n");
52 return ret;
53 }
54
55 while ((tag = av_dict_get(fmt_ctx->metadata, "", tag, AV_DICT_IGNORE_SUFFIX)))
56 printf("%s=%s\n", tag->key, tag->value);
57
59 return 0;
60}
Main libavformat public API header.
static AVFormatContext * fmt_ctx
Public dictionary API.
int avformat_open_input(AVFormatContext **ps, const char *url, const AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
AVDictionaryEntry * av_dict_get(const AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int flags)
Get a dictionary entry with matching key.
#define AV_DICT_IGNORE_SUFFIX
Return first entry in a dictionary whose first part corresponds to the search key,...
Definition: dict.h:68
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level.
int main(int argc, char **argv)
Definition: metadata.c:34
char * key
Definition: dict.h:80
char * value
Definition: dict.h:81
Format I/O context.
Definition: avformat.h:1213
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1442