diff --git a/sample/retro_sample.cpp b/sample/retro_sample.cpp
index d4b031e..a146e9b 100644
--- a/sample/retro_sample.cpp
+++ b/sample/retro_sample.cpp
@@ -85,18 +85,24 @@ int main(int argc, const char** argv)
     }
 
     Mat frame;
-    capture >> frame;
-
-    if (frame.empty())
+    const int maxAttemps = 5; // attempt to get first non-empty frame
+    int attemptIdx = 0;
+    while (frame.empty() && attemptIdx < maxAttemps)
     {
-        // empty video; lets consider this to be OK
-        return 0;
+        capture >> frame;
+        attemptIdx++;
+    }
+    if (attemptIdx == maxAttemps)
+    {
+        cout << "Error: empty first frames." << endl;
+        return 1;
     }
+    
 
     params.frameSize   = frame.size();
     RetroFilter filter(params);
 
-    for(;;)
+    while (!frame.empty())
     {
         Mat retroFrame;
         TS(filter);
@@ -110,7 +116,6 @@ int main(int argc, const char** argv)
             break;
 
         capture >> frame;
-        if(frame.empty()) break;
     }
 
     return 0;
diff --git a/src/retro_filter.cpp b/src/retro_filter.cpp
index 5956869..8bfcee1 100644
--- a/src/retro_filter.cpp
+++ b/src/retro_filter.cpp
@@ -1,5 +1,6 @@
 #include "retro_filter.hpp"
 #include "opencv2/imgproc/imgproc.hpp"
+#include <time.h>
 
 using namespace std;
 using namespace cv;
@@ -11,9 +12,8 @@ inline void alphaBlend(const Mat& src, Mat& dst, const Mat& alpha)
     src.convertTo(s, CV_32S);
     dst.convertTo(d, CV_32S);
 
-    multiply(s, w, sw);
-    multiply(d, -w, dw);
-    d = (d*255 + sw + dw)/255.0;
+    multiply(s - d, w, sw);
+    d = (d*255 + sw)/255.0;
     d.convertTo(dst, CV_8U);
 }
 
@@ -36,24 +36,25 @@ RetroFilter::RetroFilter(const Parameters& params) : rng_(time(0))
 void RetroFilter::applyToVideo(const Mat& frame, Mat& retroFrame)
 {
     int col, row;
-    Mat luminance;
+    Mat luminance; 
     cvtColor(frame, luminance, CV_BGR2GRAY);
 
     // Add scratches
-    Scalar meanColor = mean(luminance.row(luminance.rows / 2));
-    Mat scratchColor(params_.frameSize, CV_8UC1, meanColor * 2.0);
+    Scalar meanColor = mean(luminance.row(luminance.rows / 2)); //!!!
+    Mat scratchColor(params_.frameSize, CV_8UC1, meanColor * 2.0); 
     int x = rng_.uniform(0, params_.scratches.cols - luminance.cols);
     int y = rng_.uniform(0, params_.scratches.rows - luminance.rows);
 
-    for (row = 0; row < luminance.size().height; row += 1)
+    for (row = 0; row < luminance.size().height; row++)
     {
-        for (col = 0; col < luminance.size().width; col += 1)
+        for (col = 0; col < luminance.size().width; col++)
         {
-            uchar pix_color = params_.scratches.at<uchar>(row + y, col + x) ? (int)scratchColor.at<uchar>(row, col) : luminance.at<uchar>(row, col);
-            luminance.at<uchar>(row, col) = pix_color;
+             luminance.at<uchar>(row, col) = params_.scratches.at<uchar>(row + y, col + x) ? (int)scratchColor.at<uchar>(row, col) : luminance.at<uchar>(row, col);           
         }
     }
 
+
+
     // Add fuzzy border
     Mat borderColor(params_.frameSize, CV_32FC1, Scalar::all(meanColor[0] * 1.5));
     alphaBlend(borderColor, luminance, params_.fuzzyBorder);
@@ -61,21 +62,13 @@ void RetroFilter::applyToVideo(const Mat& frame, Mat& retroFrame)
 
     // Apply sepia-effect
     retroFrame.create(luminance.size(), CV_8UC3);
-    Mat hsv_pixel(1, 1, CV_8UC3);
-    Mat rgb_pixel(1, 1, CV_8UC3);
-    for (col = 0; col < luminance.size().width; col += 1)
-    {
-        for (row = 0; row < luminance.size().height; row += 1)
-        {
-            hsv_pixel.ptr()[2] = cv::saturate_cast<uchar>(luminance.at<uchar>(row, col) * hsvScale_ + hsvOffset_);
-            hsv_pixel.ptr()[0] = 19;
-            hsv_pixel.ptr()[1] = 78;
+    vector<Mat> channels; 
+    split(retroFrame, channels);
+    channels[0] = 19;
+    channels[1] = 78;
+    channels[2] = luminance * hsvScale_ + hsvOffset_;
+    merge(channels, retroFrame);
 
-            cvtColor(hsv_pixel, rgb_pixel, CV_HSV2RGB);
+    cvtColor(retroFrame, retroFrame, CV_HSV2BGR);
 
-            retroFrame.at<Vec3b>(row, col)[0] = rgb_pixel.ptr()[2];
-            retroFrame.at<Vec3b>(row, col)[1] = rgb_pixel.ptr()[1];
-            retroFrame.at<Vec3b>(row, col)[2] = rgb_pixel.ptr()[0];
-        }
-    }
 }