3 files changed, 51 insertions, 0 deletions

diff --git a/video-opencv/impl-camera.cpp b/video-opencv/impl-camera.cpp
index 662eceb2..afd76310 100644
--- a/video-opencv/impl-camera.cpp
+++ b/video-opencv/impl-camera.cpp
@@ -1,6 +1,7 @@
 #include "impl.hpp"
 #include "compat/sleep.hpp"
 #include "video-property-page.hpp"
+#include <QDebug>
 
 namespace opencv_camera_impl {
 
@@ -30,6 +31,34 @@ bool cam::is_open()
     return !!cap;
 }
 
+void cam::set_exposure(bool write)
+{
+    auto e = *s.exposure;
+    if (e != exposure)
+        switch (e)
+        {
+            case exposure_preset::near: cap->set(cv::CAP_PROP_EXPOSURE, -5); qDebug() << "near"; break;
+            case exposure_preset::far: cap->set(cv::CAP_PROP_EXPOSURE, -4); qDebug() << "far"; break;
+            default: break;
+        }
+
+    if (s.exposure != exposure_preset::ignored)
+    {
+        constexpr struct {
+            int prop, value;
+        } props[] = {
+            { cv::CAP_PROP_AUTO_EXPOSURE,   0 },
+            { cv::CAP_PROP_BRIGHTNESS,      0 },
+            { cv::CAP_PROP_SHARPNESS,       3 },
+        };
+        for (const auto [prop, value] : props)
+            cap->set(prop, value);
+    }
+
+    if (write)
+        exposure = e;
+}
+
 bool cam::start(info& args)
 {
     stop();
@@ -46,6 +75,8 @@ bool cam::start(info& args)
     if (args.use_mjpeg)
         cap->set(cv::CAP_PROP_FOURCC, cv::VideoWriter::fourcc('M', 'J', 'P', 'G'));
 
+    set_exposure(false);
+
     if (!cap->isOpened())
         goto fail;
 
@@ -82,6 +113,8 @@ bool cam::get_frame_()
         portable::sleep(50);
     }
 
+    set_exposure(true);
+
     return false;
 }
 
diff --git a/video-opencv/impl.hpp b/video-opencv/impl.hpp
index ed5499b0..8e61989e 100644
--- a/video-opencv/impl.hpp
+++ b/video-opencv/impl.hpp
@@ -8,6 +8,7 @@
 #pragma once
 
 #include "video/camera.hpp"
+#include "settings.hpp"
 #include <optional>
 #include <opencv2/videoio.hpp>
 
@@ -43,13 +44,17 @@ static constexpr int video_capture_backend =
     bool is_open() override;
     std::tuple<const frame&, bool> get_frame() override;
     bool show_dialog() override;
+    void set_exposure(bool write);
 
     bool get_frame_();
 
+    dshow_camera_settings s;
+
     std::optional<cv::VideoCapture> cap;
     cv::Mat mat;
     frame frame_;
     int idx = -1;
+    exposure_preset exposure = exposure_preset::ignored;
 };
 
 } // ns opencv_camera_impl
diff --git a/video-opencv/settings.hpp b/video-opencv/settings.hpp
new file mode 100644
index 00000000..a4f70c25
--- /dev/null
+++ b/video-opencv/settings.hpp
@@ -0,0 +1,13 @@
+#pragma once
+#include "options/value.hpp"
+using namespace options;
+
+enum class exposure_preset : int {
+    near, far, ignored,
+    DEFAULT = near,
+};
+
+struct dshow_camera_settings final {
+    bundle b = make_bundle("video-camera");
+    value<exposure_preset> exposure{b, "exposure-preset", exposure_preset::near};
+};