1 files changed, 110 insertions, 0 deletions
diff --git a/src/image.cpp b/src/image.cpp
new file mode 100644
index 0000000..a9280a4
--- /dev/null
+++ b/src/image.cpp
@@ -0,0 +1,110 @@
+#include "image.h"
+
+#include "macro.h"
+#include "pixels.h"
+
+float process_column(const uint16_t (&column)[])
+{
+    start_timer(process_column);
+
+    float result = std::numeric_limits<float>::quiet_NaN();
+
+    constexpr uint32_t signalThreshold = 900; // = SKO * sqrt(patternSize)
+    static constexpr uint32_t patternOffset = patternSize -
+                                              ((patternSize % 2 == 1) ? 1 : 0);
+    const uint32_t correlationSize = img_height - patternSize +
+                                     ((patternSize % 2 == 1) ? 1 : 0);
+    uint32_t correlation[img_height];
+    uint32_t integralSum[img_height];
+    uint32_t maxSum = signalThreshold * 50;
+    uint32_t x1 = 0;
+    int32_t y1 = 0;
+    int32_t y2 = 0;
+
+    memset(correlation, 0, img_height * sizeof(correlation[0]));
+    integralSum[0] = 0;
+
+    for (uint32_t i = 1; i < img_height; ++i)
+    {
+        // if (column[i] < 100)
+        // {
+        //     column[i] = 0;
+        // }
+
+        integralSum[i] = column[i] / 256 + integralSum[i - 1];
+    }
+
+    for (uint32_t i = 0; i < correlationSize; ++i)
+        correlation[i + patternSize / 2] = column[i + patternSize / 2] / 256 *
+                                           (integralSum[i + patternOffset] -
+                                            integralSum[i]);
+
+    for (uint32_t i = 3; i < img_height - 2; ++i)
+    {
+        const auto sum = correlation[i - 1] + correlation[i] +
+                         correlation[i + 1];
+
+        if (sum > maxSum)
+        {
+            const int32_t rioux0 = int32_t(correlation[i - 2 - 1] +
+                                           correlation[i - 1 - 1]) -
+                                   int32_t(correlation[i + 1 - 1] +
+                                           correlation[i + 2 - 1]);
+
+            if (rioux0 < 0)
+            {
+                const int32_t rioux1 = int32_t(correlation[i - 2] +
+                                               correlation[i - 1]) -
+                                       int32_t(correlation[i + 1] +
+                                               correlation[i + 2]);
+
+                if (rioux1 >= 0)
+                {
+                    x1 = i - 1;
+                    y1 = rioux0;
+                    y2 = rioux1;
+                    maxSum = sum;
+                }
+            }
+        }
+    }
+
+    result = (y2 != y1) ? (float(x1) - (float(y1) / (y2 - y1)))
+                        : std::numeric_limits<float>::quiet_NaN();
+
+    return result;
+}
+
+void Image::rotate()
+{
+    start_timer(rotate);
+
+    using namespace std;
+
+    for (size_t i = 0; i < img_height; ++i)
+    {
+        for (size_t j = 0; j < img_width; ++j)
+        {
+            rotated_cw[j][i] = data[img_height - i][j];
+        }
+    }
+
+    stop_timer(rotate);
+}
+
+std::shared_ptr<Pixels> Image::pixels() const
+{
+    auto result = std::make_shared<Pixels>();
+    result->counters = counters;
+
+    start_timer(process_columns);
+
+    for (size_t i = 0; i < width; i++)
+    {
+        result->pixels[i] = process_column(rotated_cw[i]);
+    }
+
+    stop_timer(process_columns);
+
+    return result;
+}