| 1 | /* |
| 2 | * Copyright (c) 2014 Stefano Sabatini |
| 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 | * libavformat AVIOContext API example. |
| 26 | * |
| 27 | * Make libavformat demuxer access media content through a custom |
| 28 | * AVIOContext read callback. |
| 29 | * @example avio_reading.c |
| 30 | */ |
| 31 | |
| 32 | #include <libavcodec/avcodec.h> |
| 33 | #include <libavformat/avformat.h> |
| 34 | #include <libavformat/avio.h> |
| 35 | #include <libavutil/file.h> |
| 36 | |
| 37 | struct buffer_data { |
| 38 | uint8_t *ptr; |
| 39 | size_t size; ///< size left in the buffer |
| 40 | }; |
| 41 | |
| 42 | static int read_packet(void *opaque, uint8_t *buf, int buf_size) |
| 43 | { |
| 44 | struct buffer_data *bd = (struct buffer_data *)opaque; |
| 45 | buf_size = FFMIN(buf_size, bd->size); |
| 46 | |
| 47 | printf("ptr:%p size:%zu\n", bd->ptr, bd->size); |
| 48 | |
| 49 | /* copy internal buffer data to buf */ |
| 50 | memcpy(buf, bd->ptr, buf_size); |
| 51 | bd->ptr += buf_size; |
| 52 | bd->size -= buf_size; |
| 53 | |
| 54 | return buf_size; |
| 55 | } |
| 56 | |
| 57 | int main(int argc, char *argv[]) |
| 58 | { |
| 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; |
| 64 | int ret = 0; |
| 65 | struct buffer_data bd = { 0 }; |
| 66 | |
| 67 | if (argc != 2) { |
| 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]); |
| 71 | return 1; |
| 72 | } |
| 73 | input_filename = argv[1]; |
| 74 | |
| 75 | /* register codecs and formats and other lavf/lavc components*/ |
| 76 | av_register_all(); |
| 77 | |
| 78 | /* slurp file content into buffer */ |
| 79 | ret = av_file_map(input_filename, &buffer, &buffer_size, 0, NULL); |
| 80 | if (ret < 0) |
| 81 | goto end; |
| 82 | |
| 83 | /* fill opaque structure used by the AVIOContext read callback */ |
| 84 | bd.ptr = buffer; |
| 85 | bd.size = buffer_size; |
| 86 | |
| 87 | if (!(fmt_ctx = avformat_alloc_context())) { |
| 88 | ret = AVERROR(ENOMEM); |
| 89 | goto end; |
| 90 | } |
| 91 | |
| 92 | avio_ctx_buffer = av_malloc(avio_ctx_buffer_size); |
| 93 | if (!avio_ctx_buffer) { |
| 94 | ret = AVERROR(ENOMEM); |
| 95 | goto end; |
| 96 | } |
| 97 | avio_ctx = avio_alloc_context(avio_ctx_buffer, avio_ctx_buffer_size, |
| 98 | 0, &bd, &read_packet, NULL, NULL); |
| 99 | if (!avio_ctx) { |
| 100 | ret = AVERROR(ENOMEM); |
| 101 | goto end; |
| 102 | } |
| 103 | fmt_ctx->pb = avio_ctx; |
| 104 | |
| 105 | ret = avformat_open_input(&fmt_ctx, NULL, NULL, NULL); |
| 106 | if (ret < 0) { |
| 107 | fprintf(stderr, "Could not open input\n"); |
| 108 | goto end; |
| 109 | } |
| 110 | |
| 111 | ret = avformat_find_stream_info(fmt_ctx, NULL); |
| 112 | if (ret < 0) { |
| 113 | fprintf(stderr, "Could not find stream information\n"); |
| 114 | goto end; |
| 115 | } |
| 116 | |
| 117 | av_dump_format(fmt_ctx, 0, input_filename, 0); |
| 118 | |
| 119 | end: |
| 120 | avformat_close_input(&fmt_ctx); |
| 121 | /* note: the internal buffer could have changed, and be != avio_ctx_buffer */ |
| 122 | if (avio_ctx) { |
| 123 | av_freep(&avio_ctx->buffer); |
| 124 | av_freep(&avio_ctx); |
| 125 | } |
| 126 | av_file_unmap(buffer, buffer_size); |
| 127 | |
| 128 | if (ret < 0) { |
| 129 | fprintf(stderr, "Error occurred: %s\n", av_err2str(ret)); |
| 130 | return 1; |
| 131 | } |
| 132 | |
| 133 | return 0; |
| 134 | } |