c# - Optimize pixel image comparison using emgu cv libraries instead of for loops -

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  • i'm working on invisible watermarking c# project.

  • requirement embed watermark image cover image based on comparing each watermark image pixel each cover image pixel
    based on threshold value.

  • i have used 4 for-loops iterating through watermark image and
    cover image. works smaller image (ie: 30x30
    pixels), need optimize bigger images , find best fitting place of watermark pixel in cover image location.

  • i know not optimum way, instead of loops need suggestion of best library use in emgu cv in c# these easily.

  • please suggest way optimize piece of code bigger images. thanks.

       // iterate through watermark_img             (int x = 0; x < watermark_img.height; x++)             {                 (int y = 0; y < watermark_img.width; y++)                 {                     //iterate through cover image                     (int = 0; < cover.height; i++)                     {                         (int j = 0; j < cover.width; j++)                         {                             bgr pixel_watermark = watermark_img[x, y];                             bgr pixel_cover = cover[i, j];                              //get watermark pixel color values                              double b_wm = pixel_watermark.blue;                              double g_wm = pixel_watermark.green;                              double r_wm = pixel_watermark.red;                              //get cover image pixel color values                             double b_cov = pixel_cover.blue;                             double g_cov = pixel_cover.green;                             double r_cov = pixel_cover.red;                              //diff                             double b_diff = math.abs(b_wm - b_cov);                             double g_diff = math.abs(g_wm - g_cov);                             double r_diff = math.abs(r_wm - r_cov);                              //determine threshold ====== 7 (last 3 bits)                              int threshold = 7;                             if ((b_diff <= threshold) && (g_diff <= threshold) && (r_diff <= threshold))                             {                                 flag = true;                                 count_hit[cnt - 1]++;                                 //messagebox.show("no of pixels qualified embedding =\t", count_hit.tostring(), messageboxbuttons.ok);                              }                              else                             {                                 flag = false;                                 count_miss[cnt - 1]++;                                 // messagebox.show("pixel count lesser threshold =\t", count_miss.tostring(), messageboxbuttons.ok);                             }


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