Question

在下面的代码中我想在电影帧上应用temp_rec过滤器。

但我得错误断言失败了。

使用video_line_extractor函数提取行中像素的时间序列然后在主要我将时间过滤器应用于图像的所有行。

我知道这是一个效率低下的本机代码但我不能使用opencv内部代码函数而不是我的temp_rec函数。

 int width_frame, heigth_frame, num_frames;
 VideoCapture cap; 


void temp_rec(float* in, float* out, int w, float tau) {

    float yp;
    float tauo = 1 / tau;

    for (int i = 0; i<w;i++) {

        if (i == 0) {
            *out = tauo*(*in);
        }
        else {

            out -= 1;
            yp = *(out);
            out += 1;

            *(out) = tauo*(*(in)) + ((exp(-tauo))*yp);
        }
        out += 1;
        in += 1;//prepare for calculate next element

    }


}

Mat video_line_extractor(int whichrow) {//extract a row of frames

    // Create a VideoCapture object and open the input file
    // If the input is the web camera, pass 0 instead of the video file name
    cap = VideoCapture("a valid path");

    int frame_counter = 0;
    Mat M_temp = Mat::eye(width_frame, num_frames, CV_8UC3);

    // Check if camera opened successfully
    if (!cap.isOpened()) {
        cout << "Error opening video stream or file :(" << endl;
    }

    while (frame_counter<num_frames) {

        Mat frame;
        // Capture frame-by-frame
        cap >> frame;

        // If the frame is empty, break immediately
        if (frame.empty())
            break;

        cvtColor(frame, frame, CV_BGR2GRAY);



        for(int j=0;j<width_frame;j++) //we in above first extract a movie frame that as we know it is a image
            //in this 'for' we extract that row data with a pointer to one of the row in th M_temp  
        M_temp.at<uchar>(frame_counter , j) = frame.ptr<uchar>(whichrow)[j];

        frame_counter++;
    }

    // When everything done, release the video capture object
    cap.release();


    return M_temp;

}



int main() {

    cap=VideoCapture("a valid path");

    width_frame = cap.get(CV_CAP_PROP_FRAME_WIDTH);
    heigth_frame = cap.get(CV_CAP_PROP_FRAME_HEIGHT);
    num_frames = cap.get(CV_CAP_PROP_FRAME_COUNT);

    Mat image= Mat::zeros(width_frame, num_frames, CV_8UC3);//initalize input
    Mat image_o = Mat::zeros(width_frame, num_frames, CV_8UC3);//initialize output

    for (int jj = 0;jj < heigth_frame;jj++) {
        image = video_line_extractor(jj);

        for (int j = 0;j < width_frame;j++)
            temp_rec((float *)image.ptr<uchar>(j), (float *)image_o.ptr<uchar>(j), num_frames, 10);

    }


    imshow("Image", image);

    waitKey(0);
    return 0;
}

编辑：断言错误 https://i.stack.imgur.com/BGGu0.png

Answer 1

public async void FetchOrders()
{
    RestClient client = new RestClient("https://mws.amazonservices.de");
    client.DefaultParameters.Clear();
    client.ClearHandlers();

    Dictionary<string, string> parameters = new Dictionary<string, string>();
    parameters.Add("AWSAccessKeyId", "xxxxxxxxxx");
    parameters.Add("Action", "ListOrders");
    parameters.Add("CreatedAfter", "2018-01-01T11:34:00Z");
    parameters.Add("MarketplaceId.Id.1", "A1PA6795UKMFR9");
    parameters.Add("SellerId", "xxxxxxxxx");
    parameters.Add("SignatureVersion", "2");
    parameters.Add("Timestamp", DateTime.UtcNow.ToString("s") + "Z");
    parameters.Add("Version", "2013-09-01");

    RestRequest request = new RestRequest("Orders/2013-09-01/", Method.POST);

    string signature = AmzLibrary.SignParameters(parameters, "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx");
    request.AddParameter("Signature", signature);

    foreach (KeyValuePair<string, string> keyValuePair in parameters)
    {
        request.AddParameter(keyValuePair.Key, keyValuePair.Value);
    }

    IRestResponse result = await client.ExecuteTaskAsync(request);
}



public static class AmzLibrary
{
    public static string GetParametersAsString(IDictionary<String, String> parameters)
    {
        StringBuilder data = new StringBuilder();
        foreach (String key in (IEnumerable<String>)parameters.Keys)
        {
            String value = parameters[key];
            if (value != null)
            {
                data.Append(key);
                data.Append('=');
                data.Append(UrlEncode(value, false));
                data.Append('&');
            }
        }
        String result = data.ToString();
        return result.Remove(result.Length - 1);
    }

    public static String SignParameters(IDictionary<String, String> parameters, String key)
    {
        String signatureVersion = parameters["SignatureVersion"];

        KeyedHashAlgorithm algorithm = new HMACSHA1();

        String stringToSign = null;
        if ("2".Equals(signatureVersion))
        {
            String signatureMethod = "HmacSHA256";
            algorithm = KeyedHashAlgorithm.Create(signatureMethod.ToUpper());
            parameters.Add("SignatureMethod", signatureMethod);
            stringToSign = CalculateStringToSignV2(parameters);
        }
        else
        {
            throw new Exception("Invalid Signature Version specified");
        }

        return Sign(stringToSign, key, algorithm);
    }

    private static String CalculateStringToSignV2(IDictionary<String, String> parameters)
    {
        StringBuilder data = new StringBuilder();
        IDictionary<String, String> sorted =
              new SortedDictionary<String, String>(parameters, StringComparer.Ordinal);
        data.Append("POST");
        data.Append("\n");
        Uri endpoint = new Uri("https://mws.amazonservices.de/Orders/2013-09-01");

        data.Append(endpoint.Host);
        if (endpoint.Port != 443 && endpoint.Port != 80)
        {
            data.Append(":")
                .Append(endpoint.Port);
        }
        data.Append("\n");
        String uri = endpoint.AbsolutePath;
        if (uri == null || uri.Length == 0)
        {
            uri = "/";
        }
        data.Append(UrlEncode(uri, true));
        data.Append("\n");
        foreach (KeyValuePair<String, String> pair in sorted)
        {
            if (pair.Value != null)
            {
                data.Append(UrlEncode(pair.Key, false));
                data.Append("=");
                data.Append(UrlEncode(pair.Value, false));
                data.Append("&");
            }

        }

        String result = data.ToString();
        return result.Remove(result.Length - 1);
    }

    private static String UrlEncode(String data, bool path)
    {
        StringBuilder encoded = new StringBuilder();
        String unreservedChars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_.~" + (path ? "/" : "");

        foreach (char symbol in System.Text.Encoding.UTF8.GetBytes(data))
        {
            if (unreservedChars.IndexOf(symbol) != -1)
            {
                encoded.Append(symbol);
            }
            else
            {
                encoded.Append("%" + String.Format("{0:X2}", (int)symbol));
            }
        }

        return encoded.ToString();

    }

    private static String Sign(String data, String key, KeyedHashAlgorithm algorithm)
    {
        Encoding encoding = new UTF8Encoding();
        algorithm.Key = encoding.GetBytes(key);
        return Convert.ToBase64String(algorithm.ComputeHash(
            encoding.GetBytes(data.ToCharArray())));
    }
}

打开cv错误：断言失败（视频帧上的IIR过滤器）

1 个答案: