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我写了这段代码并尝试了其他功能，但我不能实现这个场景。我该怎么办？问题是在代码，方法还是库中？

#include <gst/gst.h>
#include <opencv2/opencv.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <gst/app/gstappsrc.h>

int main(int argc, char* argv[]) {
    // Initialize GStreamer
    gst_init(&argc, &argv);

    // Create a GStreamer pipeline
    GstElement* pipeline = gst_parse_launch("v4l2src device=/dev/video0 ! videoconvert ! video/x-raw,format=BGR ! appsink", NULL);

    // Check if the pipeline was created successfully
    if (!pipeline) {
        g_print("Pipeline could not be created. Exiting.\n");
        return -1;
    }

    // Set the pipeline state to playing
    GstStateChangeReturn ret = gst_element_set_state(pipeline, GST_STATE_PLAYING);
    if (ret == GST_STATE_CHANGE_FAILURE) {
        g_print("Unable to set the pipeline to the playing state. Exiting.\n");
        return -1;
    }

    // OpenCV VideoCapture for video capture
    cv::VideoCapture cap;

    if (!cap.open("appsrc ! videoconvert ! video/x-raw, format=YUY2,width=640,height=480,framerate=25/1 ! jpegenc ! rtpjpegpay ! appsink ! udpsink host=192.168.1.14 port=5000")) {
        std::cerr << "Error: Could not open OpenCV VideoCapture." << std::endl;
        return -1;
    }

    cv::Mat frame;
    cv::Scalar text_color(0, 255, 0); // Text color (BGR)
    int font = cv::FONT_HERSHEY_SIMPLEX;
    double font_scale = 1.0;
    int font_thickness = 2;
    std::string text = "Hello, GStreamer!";

    while (true) {
        if (!cap.read(frame)) {
            std::cerr << "Error: Could not read frame from OpenCV VideoCapture." << std::endl;
            break;
        }

        // Add text to the video frame using OpenCV
        cv::putText(frame, text, cv::Point(10, 50), font, font_scale, text_color, font_thickness);

        // Display the processed frame using OpenCV
        cv::imshow("Processed Frame", frame);
        cv::waitKey(1);

        // Convert the OpenCV frame to GStreamer format
        GstBuffer* buffer = gst_buffer_new_allocate(NULL, frame.total() * frame.elemSize(), NULL);
        GstMapInfo map_info;
        gst_buffer_map(buffer, &map_info, GST_MAP_WRITE);
        memcpy(map_info.data, frame.data, frame.total() * frame.elemSize());
        gst_buffer_unmap(buffer, &map_info);

        // Push the frame into the GStreamer pipeline
        GstFlowReturn ret = gst_app_src_push_buffer(GST_APP_SRC(gst_bin_get_by_name(GST_BIN(pipeline), "appsrc")), buffer);
        if (ret != GST_FLOW_OK) {
            g_print("Error pushing frame to GStreamer pipeline. Exiting.\n");
            break;
        }
    }

    // Clean up
    cv::destroyAllWindows();

    gst_element_set_state(pipeline, GST_STATE_NULL);
    gst_object_unref(pipeline);

    return 0;
}

我得到这个错误：
（gstreaming_and_opencv_driver：19685）：GStreamer-CRITICAL**：15：24：59.492：gst_caps_get_structure：Assert“GST_IS_CAPS（caps）”失败
（gstreaming_and_opencv_driver：19685）：GStreamer-CRITICAL**：15：24：59.492：gst_structure_get_int：assertion 'structure！= NULL' failed [ WARN：email protected(https://stackoverflow.com/cdn-cgi/l/email-protection) ] global cap_gstreamer.cpp：1707 open OpenCV| GStreamer警告：无法查询视频宽度/高度
（gstreaming_and_opencv_driver：19685）：GStreamer-CRITICAL**：15：24：59.492：gst_structure_get_fraction：assertion 'structure！= NULL' failed [ WARN：email protected(https://stackoverflow.com/cdn-cgi/l/email-protection) ] global cap_gstreamer.cpp：1713 open OpenCV| GStreamer warning：cannot query video fps [ WARN：email protected(https://stackoverflow.com/cdn-cgi/l/email-protection) ] global cap_gstreamer.cpp：1728 open OpenCV| GStreamer警告：无法查询视频位置：状态=0，值=-1，持续时间=-1
我试着写一个文本的网络摄像头视频与opencv和发送与udp的gst库。