Preview DSLR : resize 960px + base64 hors asyncio pour fluidifier liveview

backend/camera.py

@@ -200,8 +200,19 @@ class Camera:
     def _preview_gphoto2(self) -> bytes | None:
         try:
             fichier = self.camera.capture_preview()
-            donnees = fichier.get_data_and_size()
-            return bytes(donnees)
+            donnees = bytes(fichier.get_data_and_size())
+            # Redimensionner pour alléger le WebSocket
+            img = cv2.imdecode(
+                __import__("numpy").frombuffer(donnees, dtype=__import__("numpy").uint8),
+                cv2.IMREAD_COLOR,
+            )
+            if img is not None:
+                h, w = img.shape[:2]
+                if w > 960:
+                    img = cv2.resize(img, (960, int(h * 960 / w)), interpolation=cv2.INTER_LINEAR)
+                _, buf = cv2.imencode(".jpg", img, [cv2.IMWRITE_JPEG_QUALITY, 75])
+                return buf.tobytes()
+            return donnees
         except gp.GPhoto2Error as e:
             log.error(f"Erreur preview DSLR : {e}")
             return None

backend/main.py

@@ -80,7 +80,8 @@ async def _pusher_preview():
                 await diffuser_ws({"type": "camera_erreur", "message": "DSLR ne repond pas au preview"})
                 _preview_actif = False
             continue
-        b64 = base64.b64encode(donnees).decode("ascii")
+        loop = asyncio.get_event_loop()
+        b64 = await loop.run_in_executor(None, lambda d=donnees: base64.b64encode(d).decode("ascii"))
         await diffuser_ws({"type": "preview", "image": f"data:image/jpeg;base64,{b64}"})
 
 async def surveiller_dslr():