02474e907af617660c7920290b23e47944dfecae
2 * Copyright (c) 2014 Stefano Sabatini
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:
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
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
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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
25 * libavformat AVIOContext API example.
27 * Make libavformat demuxer access media content through a custom
28 * AVIOContext read callback.
29 * @example avio_reading.c
32 #include <libavcodec/avcodec.h>
33 #include <libavformat/avformat.h>
34 #include <libavformat/avio.h>
35 #include <libavutil/file.h>
39 size_t size
; ///< size left in the buffer
42 static int read_packet(void *opaque
, uint8_t *buf
, int buf_size
)
44 struct buffer_data
*bd
= (struct buffer_data
*)opaque
;
45 buf_size
= FFMIN(buf_size
, bd
->size
);
47 printf("ptr:%p size:%zu\n", bd
->ptr
, bd
->size
);
49 /* copy internal buffer data to buf */
50 memcpy(buf
, bd
->ptr
, buf_size
);
57 int main(int argc
, char *argv
[])
59 AVFormatContext
*fmt_ctx
= NULL
;
60 AVIOContext
*avio_ctx
= NULL
;
61 uint8_t *buffer
= NULL
, *avio_ctx_buffer
= NULL
;
62 size_t buffer_size
, avio_ctx_buffer_size
= 4096;
63 char *input_filename
= NULL
;
65 struct buffer_data bd
= { 0 };
68 fprintf(stderr
, "usage: %s input_file\n"
69 "API example program to show how to read from a custom buffer "
70 "accessed through AVIOContext.\n", argv
[0]);
73 input_filename
= argv
[1];
75 /* register codecs and formats and other lavf/lavc components*/
78 /* slurp file content into buffer */
79 ret
= av_file_map(input_filename
, &buffer
, &buffer_size
, 0, NULL
);
83 /* fill opaque structure used by the AVIOContext read callback */
85 bd
.size
= buffer_size
;
87 if (!(fmt_ctx
= avformat_alloc_context())) {
88 ret
= AVERROR(ENOMEM
);
92 avio_ctx_buffer
= av_malloc(avio_ctx_buffer_size
);
93 if (!avio_ctx_buffer
) {
94 ret
= AVERROR(ENOMEM
);
97 avio_ctx
= avio_alloc_context(avio_ctx_buffer
, avio_ctx_buffer_size
,
98 0, &bd
, &read_packet
, NULL
, NULL
);
100 ret
= AVERROR(ENOMEM
);
103 fmt_ctx
->pb
= avio_ctx
;
105 ret
= avformat_open_input(&fmt_ctx
, NULL
, NULL
, NULL
);
107 fprintf(stderr
, "Could not open input\n");
111 ret
= avformat_find_stream_info(fmt_ctx
, NULL
);
113 fprintf(stderr
, "Could not find stream information\n");
117 av_dump_format(fmt_ctx
, 0, input_filename
, 0);
120 avformat_close_input(&fmt_ctx
);
121 /* note: the internal buffer could have changed, and be != avio_ctx_buffer */
123 av_freep(&avio_ctx
->buffer
);
126 av_file_unmap(buffer
, buffer_size
);
129 fprintf(stderr
, "Error occurred: %s\n", av_err2str(ret
));