here have more code

src/frontend/qt_sdl/CameraManager.cpp

@@ -79,6 +79,8 @@ void CameraManager::Init()
 
     // TODO: load settings from config!!
     InputType = 0;
+    InputType = 1;
+    ImagePath = "test.jpg";
 
     {
         // fill the framebuffer with black
@@ -99,7 +101,22 @@ void CameraManager::Init()
     {
         // still image
 
-        //
+        QImage img(ImagePath);
+        if (!img.isNull())
+        {
+            QImage imgconv = img.convertToFormat(QImage::Format_RGB32);
+            if (FrameFormatYUV)
+            {
+                CopyFrame_RGBtoYUV((u32*)img.bits(), img.width(), img.height(),
+                                   FrameBuffer, FrameWidth, FrameHeight);
+            }
+            else
+            {
+                CopyFrame_Straight((u32*)img.bits(), img.width(), img.height(),
+                                   FrameBuffer, FrameWidth, FrameHeight,
+                                   false);
+            }
+        }
     }
 }
 
@@ -135,3 +152,109 @@ void CameraManager::CaptureFrame(u32* frame, int width, int height, bool yuv)
 
     FrameMutex.unlock();
 }
+
+void CameraManager::CopyFrame_Straight(u32* src, int swidth, int sheight, u32* dst, int dwidth, int dheight, bool yuv)
+{
+    if (yuv)
+    {
+        swidth /= 2;
+        dwidth /= 2;
+    }
+
+    for (int dy = 0; dy < dheight; dy++)
+    {
+        int sy = (dy * sheight) / dheight;
+
+        for (int dx = 0; dx < dwidth; dx++)
+        {
+            int sx = (dx * swidth) / dwidth;
+
+            dst[(dy * dwidth) + dx] = src[(sy * swidth) + sx];
+        }
+    }
+}
+
+void CameraManager::CopyFrame_RGBtoYUV(u32* src, int swidth, int sheight, u32* dst, int dwidth, int dheight)
+{
+    for (int dy = 0; dy < dheight; dy++)
+    {
+        int sy = (dy * sheight) / dheight;
+
+        for (int dx = 0; dx < dwidth; dx+=2)
+        {
+            int sx;
+
+            sx = (dx * swidth) / dwidth;
+            u32 pixel1 = src[sy*swidth + sx];
+
+            sx = ((dx+1) * swidth) / dwidth;
+            u32 pixel2 = src[sy*swidth + sx];
+
+            int r1 = (pixel1 >> 16) & 0xFF;
+            int g1 = (pixel1 >> 8) & 0xFF;
+            int b1 = pixel1 & 0xFF;
+
+            int r2 = (pixel2 >> 16) & 0xFF;
+            int g2 = (pixel2 >> 8) & 0xFF;
+            int b2 = pixel2 & 0xFF;
+
+            int y1 = ((r1 * 19595) + (g1 * 38470) + (b1 * 7471)) >> 16;
+            int u1 = ((b1 - y1) * 32244) >> 16;
+            int v1 = ((r1 - y1) * 57475) >> 16;
+
+            int y2 = ((r2 * 19595) + (g2 * 38470) + (b2 * 7471)) >> 16;
+            int u2 = ((b2 - y2) * 32244) >> 16;
+            int v2 = ((r2 - y2) * 57475) >> 16;
+
+            u1 += 128; v1 += 128;
+            u2 += 128; v2 += 128;
+
+            y1 = std::clamp(y1, 0, 255); u1 = std::clamp(u1, 0, 255); v1 = std::clamp(v1, 0, 255);
+            y2 = std::clamp(y2, 0, 255); u2 = std::clamp(u2, 0, 255); v2 = std::clamp(v2, 0, 255);
+
+            // huh
+            u1 = (u1 + u2) >> 1;
+            v1 = (v1 + v2) >> 1;
+
+            dst[(dy*dwidth + dx) / 2] = y1 | (u1 << 8) | (y2 << 16) | (v1 << 24);
+        }
+    }
+}
+
+void CameraManager::CopyFrame_YUVtoRGB(u32* src, int swidth, int sheight, u32* dst, int dwidth, int dheight)
+{
+    for (int dy = 0; dy < dheight; dy++)
+    {
+        int sy = (dy * sheight) / dheight;
+
+        for (int dx = 0; dx < dwidth; dx+=2)
+        {
+            int sx = (dx * swidth) / dwidth;
+            u32 val = src[(sy*swidth + sx) / 2];
+
+            int y1 = val & 0xFF;
+            int u = (val >> 8) & 0xFF;
+            int y2 = (val >> 16) & 0xFF;
+            int v = (val >> 24) & 0xFF;
+
+            u -= 128; v -= 128;
+
+            int r1 = y1 + ((v * 91881) >> 16);
+            int g1 = y1 - ((v * 46793) >> 16) - ((u * 22544) >> 16);
+            int b1 = y1 + ((u * 116129) >> 16);
+
+            int r2 = y2 + ((v * 91881) >> 16);
+            int g2 = y2 - ((v * 46793) >> 16) - ((u * 22544) >> 16);
+            int b2 = y2 + ((u * 116129) >> 16);
+
+            r1 = std::clamp(r1, 0, 255); g1 = std::clamp(g1, 0, 255); b1 = std::clamp(b1, 0, 255);
+            r2 = std::clamp(r2, 0, 255); g2 = std::clamp(g2, 0, 255); b2 = std::clamp(b2, 0, 255);
+
+            u32 col1 = (r1 << 16) | (g1 << 8) | b1;
+            u32 col2 = (r2 << 16) | (g2 << 8) | b2;
+
+            dst[dy*dwidth + dx  ] = col1;
+            dst[dy*dwidth + dx+1] = col1;
+        }
+    }
+}

src/frontend/qt_sdl/CameraManager.h

@@ -63,6 +63,10 @@ private:
     bool FrameFormatYUV;
     u32* FrameBuffer;
     QMutex FrameMutex;
+
+    void CopyFrame_Straight(u32* src, int swidth, int sheight, u32* dst, int dwidth, int dheight, bool yuv);
+    void CopyFrame_RGBtoYUV(u32* src, int swidth, int sheight, u32* dst, int dwidth, int dheight);
+    void CopyFrame_YUVtoRGB(u32* src, int swidth, int sheight, u32* dst, int dwidth, int dheight);
 };
 
 #endif // CAMERAMANAGER_H