diff --git a/docker-compose.yaml b/docker-compose.yaml
index d1ca47c..d040ed3 100755
--- a/docker-compose.yaml
+++ b/docker-compose.yaml
@@ -17,5 +17,5 @@ services:
     ports:
       - "2093:2093"
     command: >
-      /bin/bash -lc "npm ci || npm install && node server/server.js"
+      /bin/bash -lc "apt-get update -qq && apt-get install -y --no-install-recommends python3-pip && pip3 install --quiet --no-cache-dir opencv-python-headless numpy && npm ci || npm install && node server/server.js"
     restart: unless-stopped
diff --git a/public/calibration.html b/public/calibration.html
index 3fa5157..8f62262 100644
--- a/public/calibration.html
+++ b/public/calibration.html
@@ -235,7 +235,7 @@
               </select>
               <button id="btn-compute-calib">Kalibrierung berechnen</button>
 
-              <button disabled title="Folgt später">NPZ speichern</button>
+              <button id="btn-upload-npz">NPZ speichern</button>
             </div>
           </div>
 
@@ -451,6 +451,27 @@
       }
     });
 
+    // "NPZ speichern" → an Webcam-Service übertragen
+    document.getElementById('btn-upload-npz').addEventListener('click', async () => {
+      const camera = document.getElementById('cam-select-calib').value;
+      if (!camera) { logC('⚠ Bitte zuerst eine Kamera auswählen.'); return; }
+
+      logC(`NPZ wird an Webcam-Service übertragen (${camera}) …`);
+      try {
+        const r = await fetch('/api/calibration/upload-npz', {
+          method:  'POST',
+          headers: { 'Content-Type': 'application/json' },
+          body:    JSON.stringify({ camera }),
+        });
+        const d = await r.json();
+        if (d.error) { logC(`❌ Fehler: ${d.error}`); return; }
+        logC(`✅ Gespeichert: ${d.webcam?.saved}  (${d.size} Bytes)`);
+        logC(`   calibrationUrl: ${d.webcam?.calibrationUrl}`);
+      } catch (err) {
+        logC(`❌ Fehler: ${err}`);
+      }
+    });
+
     // "Kalibrierung berechnen" – SSE-Stream lesen
     document.getElementById('btn-compute-calib').addEventListener('click', async () => {
       const camera = document.getElementById('cam-select-calib').value;
diff --git a/server/server.js b/server/server.js
index 107e284..0ea7090 100755
--- a/server/server.js
+++ b/server/server.js
@@ -426,6 +426,54 @@ app.post('/api/calibration/compute', async (req, res) => {
   }
 });
 
+/**
+ * POST /api/calibration/upload-npz
+ * Liest {camera}_calibration.npz aus der aktuellen Session und
+ * schickt sie per PUT an den Webcam-Service.
+ * Body: { camera: "cam0" }
+ */
+app.post('/api/calibration/upload-npz', async (req, res) => {
+  try {
+    const { camera } = req.body ?? {};
+    if (!camera) return res.status(400).json({ error: '"camera" parameter fehlt' });
+    if (!WEBCAM_URL) return res.status(501).json({ error: 'WEBCAM_URL ist nicht konfiguriert' });
+
+    const session = await findLatestCalibSession();
+    if (!session) return res.status(400).json({ error: 'Keine Kalibrierungs-Session vorhanden' });
+
+    const npzPath = path.join(calibDataDir, session, `${camera}_calibration.npz`);
+
+    try {
+      await fsPromises.access(npzPath);
+    } catch {
+      return res.status(404).json({
+        error: `Datei nicht gefunden: ${camera}_calibration.npz — bitte zuerst "Kalibrierung berechnen".`
+      });
+    }
+
+    const npzData = await fsPromises.readFile(npzPath);
+    const putUrl  = new URL(`/api/cameras/${camera}/calibration`, WEBCAM_URL).toString();
+
+    const putRes = await fetch(putUrl, {
+      method:  'PUT',
+      headers: { 'Content-Type': 'application/octet-stream' },
+      body:    npzData,
+    });
+
+    if (!putRes.ok) {
+      const text = await putRes.text();
+      return res.status(putRes.status).json({ error: `Webcam-Service: ${putRes.status} – ${text}` });
+    }
+
+    const result = await putRes.json();
+    return res.json({ ok: true, camera, session, size: npzData.length, webcam: result });
+
+  } catch (err) {
+    console.error('calibration/upload-npz error:', err);
+    return res.status(500).json({ error: String(err) });
+  }
+});
+
 async function checkServiceReachability(name, url) {
   try {
     const controller = new AbortController();