| /* |
| * Copyright (c) 2014 Stefano Sabatini |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to deal |
| * in the Software without restriction, including without limitation the rights |
| * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| * copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| * THE SOFTWARE. |
| */ |
| |
| /** |
| * @file |
| * libavformat AVIOContext API example. |
| * |
| * Make libavformat demuxer access media content through a custom |
| * AVIOContext read callback. |
| * @example avio_reading.c |
| */ |
| |
| #include <libavcodec/avcodec.h> |
| #include <libavformat/avformat.h> |
| #include <libavformat/avio.h> |
| #include <libavutil/file.h> |
| |
| struct buffer_data { |
| uint8_t *ptr; |
| size_t size; ///< size left in the buffer |
| }; |
| |
| static int read_packet(void *opaque, uint8_t *buf, int buf_size) |
| { |
| struct buffer_data *bd = (struct buffer_data *)opaque; |
| buf_size = FFMIN(buf_size, bd->size); |
| |
| if (!buf_size) |
| return AVERROR_EOF; |
| printf("ptr:%p size:%zu\n", bd->ptr, bd->size); |
| |
| /* copy internal buffer data to buf */ |
| memcpy(buf, bd->ptr, buf_size); |
| bd->ptr += buf_size; |
| bd->size -= buf_size; |
| |
| return buf_size; |
| } |
| |
| int main(int argc, char *argv[]) |
| { |
| AVFormatContext *fmt_ctx = NULL; |
| AVIOContext *avio_ctx = NULL; |
| uint8_t *buffer = NULL, *avio_ctx_buffer = NULL; |
| size_t buffer_size, avio_ctx_buffer_size = 4096; |
| char *input_filename = NULL; |
| int ret = 0; |
| struct buffer_data bd = { 0 }; |
| |
| if (argc != 2) { |
| fprintf(stderr, "usage: %s input_file\n" |
| "API example program to show how to read from a custom buffer " |
| "accessed through AVIOContext.\n", argv[0]); |
| return 1; |
| } |
| input_filename = argv[1]; |
| |
| /* slurp file content into buffer */ |
| ret = av_file_map(input_filename, &buffer, &buffer_size, 0, NULL); |
| if (ret < 0) |
| goto end; |
| |
| /* fill opaque structure used by the AVIOContext read callback */ |
| bd.ptr = buffer; |
| bd.size = buffer_size; |
| |
| if (!(fmt_ctx = avformat_alloc_context())) { |
| ret = AVERROR(ENOMEM); |
| goto end; |
| } |
| |
| avio_ctx_buffer = av_malloc(avio_ctx_buffer_size); |
| if (!avio_ctx_buffer) { |
| ret = AVERROR(ENOMEM); |
| goto end; |
| } |
| avio_ctx = avio_alloc_context(avio_ctx_buffer, avio_ctx_buffer_size, |
| 0, &bd, &read_packet, NULL, NULL); |
| if (!avio_ctx) { |
| ret = AVERROR(ENOMEM); |
| goto end; |
| } |
| fmt_ctx->pb = avio_ctx; |
| |
| ret = avformat_open_input(&fmt_ctx, NULL, NULL, NULL); |
| if (ret < 0) { |
| fprintf(stderr, "Could not open input\n"); |
| goto end; |
| } |
| |
| ret = avformat_find_stream_info(fmt_ctx, NULL); |
| if (ret < 0) { |
| fprintf(stderr, "Could not find stream information\n"); |
| goto end; |
| } |
| |
| av_dump_format(fmt_ctx, 0, input_filename, 0); |
| |
| end: |
| avformat_close_input(&fmt_ctx); |
| |
| /* note: the internal buffer could have changed, and be != avio_ctx_buffer */ |
| if (avio_ctx) |
| av_freep(&avio_ctx->buffer); |
| avio_context_free(&avio_ctx); |
| |
| av_file_unmap(buffer, buffer_size); |
| |
| if (ret < 0) { |
| fprintf(stderr, "Error occurred: %s\n", av_err2str(ret)); |
| return 1; |
| } |
| |
| return 0; |
| } |