avformat_open_input 设置timeout 出现-10049 error 不设置timeout没问题 是什么原因

avformat_open_input是FFmpeg用来打开一个输入媒体文件的函数，而timeout是设置超时时间的参数。出现-10049 error通常是因为网络连接超时导致的，这个错误码对应的是WSAEADDRNOTAVAIL，即“无效地址”。如果你设置了timeout，那么当网络连接超时时，avformat_open_input会返回这个错误码。如果你没有设置timeout，avformat_open_input会一直等待网络连接成功，直到超时时间达到系统默认值。所以，如果你没有设置timeout，那么程序在等待网络连接成功时就不会出现错误。

相关问题

av_interleaved_write_frame 编码h264, 保存为ts格式

你可以使用FFmpeg库中的avformat和avcodec模块来实现将h264编码的视频保存为ts格式的功能。下面是一个简单的代码示例：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <libavformat/avformat.h>
#include <libavcodec/avcodec.h>

int main(int argc, char *argv[]) {
    const char *input_file = "input.h264";
    const char *output_file = "output.ts";
    AVFormatContext *in_ctx = NULL, *out_ctx = NULL;
    AVCodec *codec = NULL;
    AVCodecContext *codec_ctx = NULL;
    AVPacket packet;
    int ret = 0;

    // 打开输入文件
    if ((ret = avformat_open_input(&in_ctx, input_file, NULL, NULL)) < 0) {
        fprintf(stderr, "Error opening input file: %s\n", av_err2str(ret));
        goto end;
    }

    // 查找视频流
    if ((ret = avformat_find_stream_info(in_ctx, NULL)) < 0) {
        fprintf(stderr, "Error finding stream information: %s\n", av_err2str(ret));
        goto end;
    }

    // 打开输出文件
    if ((ret = avformat_alloc_output_context2(&out_ctx, NULL, NULL, output_file)) < 0) {
        fprintf(stderr, "Error opening output file: %s\n", av_err2str(ret));
        goto end;
    }

    // 添加视频流
    codec = avcodec_find_encoder(AV_CODEC_ID_H264);
    if (!codec) {
        fprintf(stderr, "H.264 codec not found\n");
        goto end;
    }
    codec_ctx = avcodec_alloc_context3(codec);
    codec_ctx->width = in_ctx->streams[0]->codecpar->width;
    codec_ctx->height = in_ctx->streams[0]->codecpar->height;
    codec_ctx->pix_fmt = in_ctx->streams[0]->codecpar->format;
    codec_ctx->time_base = in_ctx->streams[0]->time_base;
    if ((ret = avcodec_open2(codec_ctx, codec, NULL)) < 0) {
        fprintf(stderr, "Error opening codec: %s\n", av_err2str(ret));
        goto end;
    }
    AVStream *out_stream = avformat_new_stream(out_ctx, codec);
    if (!out_stream) {
        fprintf(stderr, "Error creating output stream\n");
        goto end;
    }
    out_stream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
    out_stream->codecpar->codec_id = codec->id;
    out_stream->codecpar->width = codec_ctx->width;
    out_stream->codecpar->height = codec_ctx->height;
    out_stream->codecpar->format = codec_ctx->pix_fmt;
    out_stream->codecpar->bit_rate = codec_ctx->bit_rate;
    out_stream->codecpar->extradata = codec_ctx->extradata;
    out_stream->codecpar->extradata_size = codec_ctx->extradata_size;
    avcodec_parameters_to_context(out_stream->codec, out_stream->codecpar);

    // 打开输出文件
    if (!(out_ctx->oformat->flags & AVFMT_NOFILE)) {
        if ((ret = avio_open(&out_ctx->pb, output_file, AVIO_FLAG_WRITE)) < 0) {
            fprintf(stderr, "Error opening output file: %s\n", av_err2str(ret));
            goto end;
        }
    }

    // 写文件头
    if ((ret = avformat_write_header(out_ctx, NULL)) < 0) {
        fprintf(stderr, "Error writing header: %s\n", av_err2str(ret));
        goto end;
    }

    // 读取并编码每一帧
    while (1) {
        AVStream *in_stream = in_ctx->streams[0];
        if ((ret = av_read_frame(in_ctx, &packet)) < 0) {
            break;
        }
        if (packet.stream_index != 0) {
            av_packet_unref(&packet);
            continue;
        }
        av_packet_rescale_ts(&packet, in_stream->time_base, codec_ctx->time_base);
        if ((ret = avcodec_send_packet(codec_ctx, &packet)) < 0) {
            fprintf(stderr, "Error sending packet to encoder: %s\n", av_err2str(ret));
            av_packet_unref(&packet);
            break;
        }
        while (1) {
            AVFrame *frame = av_frame_alloc();
            if (!frame) {
                fprintf(stderr, "Error allocating frame\n");
                ret = AVERROR(ENOMEM);
                goto end;
            }
            ret = avcodec_receive_frame(codec_ctx, frame);
            if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
                av_frame_free(&frame);
                break;
            } else if (ret < 0) {
                fprintf(stderr, "Error receiving frame from encoder: %s\n", av_err2str(ret));
                av_frame_free(&frame);
                goto end;
            }
            frame->pts = frame->best_effort_timestamp;
            AVPacket out_packet;
            av_init_packet(&out_packet);
            out_packet.data = NULL;
            out_packet.size = 0;
            if ((ret = avcodec_send_frame(codec_ctx, frame)) < 0) {
                fprintf(stderr, "Error sending frame to encoder: %s\n", av_err2str(ret));
                av_frame_free(&frame);
                goto end;
            }
            while (1) {
                ret = avcodec_receive_packet(codec_ctx, &out_packet);
                if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
                    av_packet_unref(&out_packet);
                    break;
                } else if (ret < 0) {
                    fprintf(stderr, "Error receiving packet from encoder: %s\n", av_err2str(ret));
                    av_packet_unref(&out_packet);
                    goto end;
                }
                out_packet.stream_index = 0;
                av_packet_rescale_ts(&out_packet, codec_ctx->time_base, out_stream->time_base);
                if ((ret = av_interleaved_write_frame(out_ctx, &out_packet)) < 0) {
                    fprintf(stderr, "Error writing packet to output file: %s\n", av_err2str(ret));
                    av_packet_unref(&out_packet);
                    goto end;
                }
                av_packet_unref(&out_packet);
            }
            av_frame_free(&frame);
        }
        av_packet_unref(&packet);
    }

    // 写文件尾
    if ((ret = av_write_trailer(out_ctx)) < 0) {
        fprintf(stderr, "Error writing trailer: %s\n", av_err2str(ret));
        goto end;
    }

end:
    if (codec_ctx) {
        avcodec_free_context(&codec_ctx);
    }
    if (in_ctx) {
        avformat_close_input(&in_ctx);
    }
    if (out_ctx) {
        if (!(out_ctx->oformat->flags & AVFMT_NOFILE)) {
            avio_closep(&out_ctx->pb);
        }
        avformat_free_context(out_ctx);
    }
    return ret;
}

需要注意的是，这只是一个简单的示例代码，实际使用时需要根据具体的需求进行修改和完善。

./ffmpeg_g -re -i /home/tsdl/Downloads/test0524.mp4 -vcodec libx264 -profile:v baseline -r 25 -g 50 -f rtc "http://192.168.114.34:1985/rtc/v1/whip/?app=live&stream=livestream"生成C代码示例

以下是使用FFmpeg库生成相应的C代码示例，可以实现将本地视频文件实时推流到指定的RTMP服务器：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <unistd.h>

#include <libavformat/avformat.h>
#include <libavcodec/avcodec.h>
#include <libavutil/avutil.h>

int main(int argc, char **argv)
{
    AVFormatContext *fmt_ctx = NULL;
    AVCodecContext *video_enc_ctx = NULL;
    AVCodec *video_enc = NULL;
    AVStream *video_stream = NULL;
    AVOutputFormat *out_fmt = NULL;
    AVIOContext *out_io_ctx = NULL;
    AVFormatContext *out_fmt_ctx = NULL;
    AVPacket pkt;
    int ret;

    char *in_filename = "/home/tsdl/Downloads/test0524.mp4";
    char *out_filename = "http://192.168.114.34:1985/rtc/v1/whip/?app=live&stream=livestream";

    // 注册所有的编解码器、封装器和协议
    av_register_all();
    avformat_network_init();

    // 打开输入文件
    if ((ret = avformat_open_input(&fmt_ctx, in_filename, NULL, NULL)) < 0) {
        fprintf(stderr, "Could not open input file '%s'\n", in_filename);
        goto end;
    }

    // 查找流信息
    if ((ret = avformat_find_stream_info(fmt_ctx, NULL)) < 0) {
        fprintf(stderr, "Could not find stream information\n");
        goto end;
    }

    // 选择视频流
    int video_stream_index = av_find_best_stream(fmt_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &video_enc, 0);
    if (video_stream_index < 0) {
        fprintf(stderr, "Could not find video stream in input file '%s'\n", in_filename);
        goto end;
    }

    // 打开视频解码器
    video_enc_ctx = avcodec_alloc_context3(video_enc);
    if (!video_enc_ctx) {
        fprintf(stderr, "Could not allocate video encoder context\n");
        goto end;
    }

    if ((ret = avcodec_parameters_to_context(video_enc_ctx, fmt_ctx->streams[video_stream_index]->codecpar)) < 0) {
        fprintf(stderr, "Could not copy video codec parameters to encoder context\n");
        goto end;
    }

    if ((ret = avcodec_open2(video_enc_ctx, video_enc, NULL)) < 0) {
        fprintf(stderr, "Could not open video encoder\n");
        goto end;
    }

    // 创建输出格式上下文
    if ((ret = avformat_alloc_output_context2(&out_fmt_ctx, NULL, "rtmp", out_filename)) < 0) {
        fprintf(stderr, "Could not allocate output format context\n");
        goto end;
    }

    // 创建输出流
    video_stream = avformat_new_stream(out_fmt_ctx, NULL);
    if (!video_stream) {
        fprintf(stderr, "Could not allocate video output stream\n");
        goto end;
    }

    // 复制编解码器参数
    if ((ret = avcodec_parameters_copy(video_stream->codecpar, fmt_ctx->streams[video_stream_index]->codecpar)) < 0) {
        fprintf(stderr, "Could not copy video codec parameters\n");
        goto end;
    }

    // 设置输出流时间基准
    video_stream->time_base = video_enc_ctx->time_base;

    // 打开输出IO上下文
    if ((ret = avio_open2(&out_io_ctx, out_filename, AVIO_FLAG_WRITE, NULL, NULL)) < 0) {
        fprintf(stderr, "Could not open output url '%s'\n", out_filename);
        goto end;
    }

    out_fmt_ctx->pb = out_io_ctx;

    // 写入输出格式头部
    if ((ret = avformat_write_header(out_fmt_ctx, NULL)) < 0) {
        fprintf(stderr, "Could not write output format header\n");
        goto end;
    }

    // 初始化AVPacket
    av_init_packet(&pkt);
    pkt.data = NULL;
    pkt.size = 0;

    // 读取并编码视频帧
    while (1) {
        AVStream *in_stream, *out_stream;
        AVFrame *frame = av_frame_alloc();

        if ((ret = av_read_frame(fmt_ctx, &pkt)) < 0) {
            break;
        }

        if (pkt.stream_index == video_stream_index) {
            avcodec_send_packet(video_enc_ctx, &pkt);

            while (ret >= 0) {
                ret = avcodec_receive_frame(video_enc_ctx, frame);
                if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
                    break;
                } else if (ret < 0) {
                    fprintf(stderr, "Error while receiving a video frame from the encoder\n");
                    goto end;
                }

                // 编码并发送视频帧
                av_packet_unref(&pkt);
                av_init_packet(&pkt);

                ret = avcodec_send_frame(video_enc_ctx, frame);
                if (ret < 0) {
                    fprintf(stderr, "Error while sending a video frame to the encoder\n");
                    goto end;
                }

                while (ret >= 0) {
                    ret = avcodec_receive_packet(video_enc_ctx, &pkt);
                    if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
                        break;
                    } else if (ret < 0) {
                        fprintf(stderr, "Error while receiving a video packet from the encoder\n");
                        goto end;
                    }

                    // 发送视频包到输出流
                    av_packet_rescale_ts(&pkt, video_enc_ctx->time_base, video_stream->time_base);
                    pkt.stream_index = video_stream->index;
                    av_interleaved_write_frame(out_fmt_ctx, &pkt);

                    av_packet_unref(&pkt);
                    av_init_packet(&pkt);
                }
            }

            av_frame_unref(frame);
        }

        av_packet_unref(&pkt);
    }

    // 写入输出格式尾部
    av_write_trailer(out_fmt_ctx);

end:
    if (video_enc_ctx) {
        avcodec_free_context(&video_enc_ctx);
    }

    if (fmt_ctx) {
        avformat_close_input(&fmt_ctx);
    }

    if (out_fmt_ctx) {
        avio_closep(&out_fmt_ctx->pb);
        avformat_free_context(out_fmt_ctx);
    }

    if (out_io_ctx) {
        av_freep(&out_io_ctx->buffer);
        av_free(out_io_ctx);
    }

    if (ret < 0) {
        fprintf(stderr, "Error occurred: %s\n", av_err2str(ret));
        return 1;
    }

    return 0;
}

注意需要将代码中的输入文件路径和输出URL替换为实际的路径和URL。另外，还需要在编译时链接FFmpeg库，例如使用gcc编译器编译上述代码的命令为：

gcc -o ffmpeg_push_stream ffmpeg_push_stream.c -lavformat -lavcodec -lavutil -lm