Canon LiveView : activer viewfinder gphoto2 avant capture_preview

backend/camera.py

@@ -199,6 +199,32 @@ class Camera:
         else:
             return None  # Pas de simulation ni webcam en dehors du mode dedie
 
+    def activer_viewfinder(self):
+        """Active le LiveView sur les Canon (nécessaire avant capture_preview)."""
+        if self.mode != "gphoto2" or not self.connectee:
+            return
+        try:
+            cfg = self.camera.get_config()
+            vf = cfg.get_child_by_name("viewfinder")
+            vf.set_value(1)
+            self.camera.set_config(cfg)
+            log.info("Viewfinder activé")
+        except Exception as e:
+            log.warning(f"Viewfinder non supporté : {e}")
+
+    def desactiver_viewfinder(self):
+        """Désactive le LiveView."""
+        if self.mode != "gphoto2" or not self.connectee:
+            return
+        try:
+            cfg = self.camera.get_config()
+            vf = cfg.get_child_by_name("viewfinder")
+            vf.set_value(0)
+            self.camera.set_config(cfg)
+            log.info("Viewfinder désactivé")
+        except Exception as e:
+            log.warning(f"Viewfinder non supporté : {e}")
+
     def _preview_gphoto2(self) -> bytes | None:
         try:
             fichier = self.camera.capture_preview()

backend/main.py

@@ -686,9 +686,11 @@ async def traiter_message_ws(msg: dict, ws: WebSocket):
         await ws.send_json({"type": "pong"})
     elif type_msg == "preview_start":
         global _preview_actif
+        camera.activer_viewfinder()
         _preview_actif = True
     elif type_msg == "preview_stop":
         _preview_actif = False
+        camera.desactiver_viewfinder()
 
 
 async def diffuser_ws(message: dict):