diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2695750..25e7762 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -94,15 +94,9 @@ endif()
 find_package(PkgConfig REQUIRED)
 find_package(OpenCV REQUIRED)
 
-# include_directories("/usr/include/opencv4")
 include_directories( ${OpenCV_INCLUDE_DIRS})
 target_link_libraries(checks-parser PRIVATE -lzbar)
 target_link_libraries(checks-parser PRIVATE -ltesseract)
 target_link_libraries(checks-parser PRIVATE -lcurl)
 
-# pkg_search_module(opencv REQUIRED IMPORTED_TARGET opencv)
-# target_link_libraries(checks-parser PRIVATE -lopencv4)
 target_link_libraries( checks-parser PRIVATE ${OpenCV_LIBS} )
-# target_link_libraries(checks-parser PRIVATE PkgConfig::opencv)
-# target_link_libraries(checks-parser PRIVATE ${OpenCV_LIBS})
-# target_link_libraries(checks-parser PRIVATE -lopencv)
diff --git a/adjustpicturedialog.cpp b/adjustpicturedialog.cpp
index 9f50413..40d6634 100644
--- a/adjustpicturedialog.cpp
+++ b/adjustpicturedialog.cpp
@@ -4,23 +4,24 @@
 #include <opencv2/imgcodecs.hpp>
 #include <opencv2/imgproc.hpp>
 #include <string>
-#include <iostream>
 #include <opencv2/core/mat.hpp>
+#include <QColorTransform>
 #include <QFileDialog>
 #include <QMessageBox>
 #include <zbar.h>
 
 AdjustPictureDialog::AdjustPictureDialog(QWidget *parent, std::string imagePath)
     : QDialog(parent)
-    , ui(new Ui::AdjustPictureDialog){
+    , ui(new Ui::AdjustPictureDialog)
+    , pixmap(QString::fromStdString(imagePath))
+    , img(pixmap.toImage()){
     ui->setupUi(this);
 
+    computeContrastLookupTable();
+
     scene = new QGraphicsScene(this);
 
     ui->graphicsView->setScene(scene);
-    QGraphicsPixmapItem p;
-    QString path = QString::fromStdString(imagePath);
-    QPixmap pixmap = QPixmap(path);
     scene->addPixmap(pixmap);
 }
 
@@ -66,12 +67,39 @@ std::string AdjustPictureDialog::decode() {
         result = symbol->get_data();
     }
 
-
-
     return result;
 }
 
-void AdjustPictureDialog::on_contrastSlider_sliderMoved(int position) {
+void AdjustPictureDialog::computeContrastLookupTable() {
 
+    for (int contrastValue = 0; contrastValue < 100; ++contrastValue) {
+        double contrast = contrastValue / 50.0;
+        for (int i = 0; i < 256; ++i) {
+            unsigned short correctedValue = std::clamp(static_cast<int>(128 + contrast * (i - 128)), 0, 255);
+            contrastLUT[contrastValue].push_back(correctedValue);
+        }
+    }
+}
+
+void AdjustPictureDialog::on_contrastSlider_sliderMoved(int position) {
+    QImage image = img.copy();
+
+    uint32_t* pixels = reinterpret_cast<uint32_t*>(image.bits());
+    int width = image.width();
+    int height = image.height();
+
+    for (int y = 0; y < height; ++y) {
+        for (int x = 0; x < width; ++x) {
+            QRgb rgb = pixels[y * width + x];
+            pixels[y * width + x] = qRgba(
+                contrastLUT[position][qRed(rgb)],
+                contrastLUT[position][qGreen(rgb)],
+                contrastLUT[position][qBlue(rgb)],
+                qAlpha(rgb));
+        }
+    }
+
+    scene->clear();
+    scene->addPixmap(QPixmap::fromImage(image));
 }
 
diff --git a/adjustpicturedialog.h b/adjustpicturedialog.h
index 9fefcb2..b3feef9 100644
--- a/adjustpicturedialog.h
+++ b/adjustpicturedialog.h
@@ -16,7 +16,11 @@ public:
     explicit AdjustPictureDialog(QWidget *parent = nullptr, std::string imagePath = "");
     ~AdjustPictureDialog();
     std::string decode();
+    QPixmap pixmap;
+    QImage img;
 
+    void computeContrastLookupTable();
+    std::vector<unsigned short> contrastLUT[100];
 signals:
     void decodedData(std::string data);
 
diff --git a/image_redactor/imageredactor.h b/image_redactor/imageredactor.h
index bf050ff..96444d9 100644
--- a/image_redactor/imageredactor.h
+++ b/image_redactor/imageredactor.h
@@ -12,6 +12,7 @@ class ImageRedactor : public QGraphicsView
     Q_OBJECT
 public:
     ImageRedactor(QWidget *parent = nullptr);
+    QGraphicsScene *scene;
 protected:
     void wheelEvent(QWheelEvent *event);
 
@@ -20,7 +21,6 @@ protected:
     void mouseReleaseEvent(QMouseEvent *event);
 
 private:
-    QGraphicsScene *scene;
     QGraphicsPixmapItem *item;
 };
 
diff --git a/mainwindow.cpp b/mainwindow.cpp
index ed3b1cb..fa9fbd2 100644
--- a/mainwindow.cpp
+++ b/mainwindow.cpp
@@ -58,13 +58,14 @@ std::string MainWindow::makeRequestToOfd(std::string captcha) {
         ui->total_edit->text().toDouble() * 100,
         captcha);
 
-    return checkContent
+    return checkContent;
 }
 
 void MainWindow::receiveSolvedCaptcha(std::string captcha) {
 
     std::string check_content = makeRequestToOfd(captcha);
 
+    std::cout << check_content << std::endl;
 
 }