RTSP clent use FFMPEG/SDL2 for 720P

rtsp_client.c

#include <libavformat/avformat.h>
#include <libavcodec/avcodec.h>
#include <libavutil/imgutils.h>
#include <libavutil/time.h>
#include <SDL2/SDL.h>
#include <stdio.h>
#include <stdlib.h>

#define RTSP_URL "rtsp://172.32.0.93:554/live/0"

int main() {
    // 禁用 FFmpeg 日誌
    av_log_set_level(AV_LOG_QUIET);

    // 初始化 FFmpeg
    AVFormatContext *fmt_ctx = NULL;
    AVCodecContext *dec_ctx = NULL;
    AVCodec *decoder = NULL;
    AVFrame *frame = NULL;
    AVPacket *pkt = NULL;

    // 開啟 RTSP 串流
    AVDictionary *opts = NULL;
    av_dict_set(&opts, "rtsp_transport", "udp", 0); // 使用 UDP 傳輸
    av_dict_set(&opts, "max_delay", "100000", 0);  // 最大延遲 100ms
    av_dict_set(&opts, "buffer_size", "131072", 0); // 緩衝區大小 128KB
    av_dict_set(&opts, "probesize", "8192", 0);
    av_dict_set(&opts, "analyzeduration", "100000", 0);
    if (avformat_open_input(&fmt_ctx, RTSP_URL, NULL, &opts) < 0) {
        fprintf(stderr, "Failed to open RTSP stream\n");
        return -1;
    }
    av_dict_free(&opts);

    if (avformat_find_stream_info(fmt_ctx, NULL) < 0) {
        fprintf(stderr, "Failed to find stream info\n");
        return -1;
    }

    // 尋找視頻流
    int video_stream_idx = -1;
    for (unsigned int i = 0; i < fmt_ctx->nb_streams; i++) {
        if (fmt_ctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
            video_stream_idx = i;
            break;
        }
    }
    if (video_stream_idx == -1) {
        fprintf(stderr, "No video stream found\n");
        return -1;
    }

    // 初始化解碼器
    decoder = avcodec_find_decoder(fmt_ctx->streams[video_stream_idx]->codecpar->codec_id);
    if (!decoder) {
        fprintf(stderr, "Decoder not found\n");
        return -1;
    }

    dec_ctx = avcodec_alloc_context3(decoder);
    if (!dec_ctx) {
        fprintf(stderr, "Failed to allocate codec context\n");
        return -1;
    }
    avcodec_parameters_to_context(dec_ctx, fmt_ctx->streams[video_stream_idx]->codecpar);

    if (avcodec_open2(dec_ctx, decoder, NULL) < 0) {
        fprintf(stderr, "Failed to open codec\n");
        return -1;
    }

    // 初始化 SDL
    if (SDL_Init(SDL_INIT_VIDEO) < 0) {
        fprintf(stderr, "SDL init failed: %s\n", SDL_GetError());
        return -1;
    }

    SDL_Window *window = SDL_CreateWindow("Camera", SDL_WINDOWPOS_UNDEFINED,
                                          SDL_WINDOWPOS_UNDEFINED, 1280, 720, 0);
    SDL_Renderer *renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
    SDL_Texture *texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_IYUV,
                                            SDL_TEXTUREACCESS_STREAMING, 1280, 720);

    // 初始化 FFmpeg 幀
    frame = av_frame_alloc();
    if (!frame) {
        fprintf(stderr, "Failed to allocate frame\n");
        return -1;
    }

    pkt = av_packet_alloc();
    if (!pkt) {
        fprintf(stderr, "Failed to allocate packet\n");
        return -1;
    }

    // 主迴圈
    SDL_Event event;
    while (1) {
        if (av_read_frame(fmt_ctx, pkt) < 0) {
            break;
        }

        if (pkt->stream_index == video_stream_idx) {
            if (avcodec_send_packet(dec_ctx, pkt) < 0) {
		av_packet_unref(pkt);
                continue;
            }

            while (avcodec_receive_frame(dec_ctx, frame) == 0) {
                // 渲染到 SDL
                SDL_UpdateYUVTexture(texture, NULL,
                                     frame->data[0], frame->linesize[0],
                                     frame->data[1], frame->linesize[1],
                                     frame->data[2], frame->linesize[2]);
                SDL_RenderClear(renderer);
                SDL_RenderCopy(renderer, texture, NULL, NULL);
                SDL_RenderPresent(renderer);
            }
        }
        av_packet_unref(pkt);

        // 處理 SDL 事件
        while (SDL_PollEvent(&event)) {
            if (event.type == SDL_QUIT) {
                goto cleanup;
            }
        }
    }

cleanup:
    SDL_DestroyTexture(texture);
    SDL_DestroyRenderer(renderer);
    SDL_DestroyWindow(window);
    SDL_Quit();
    av_frame_free(&frame);
    avcodec_free_context(&dec_ctx);
    avformat_close_input(&fmt_ctx);
    return 0;
}