Session 2026-04-20: Medien-Konvertierung, Umami Analytics, Username/Privacy

- HEIC→JPEG, MOV/AVI→MP4 Konvertierung bei allen Upload-Endpoints (media_utils.py)
- ffmpeg im Docker-Image, Video-Thumbnails (extract_video_thumb, poster-Attribut)
- Google Analytics entfernt, Umami self-hosted eingebunden (index.html, datenschutz.js)
- Admin-Panel Analytics-Tab: Stat-Cards, Sparkline 7 Tage, Top-Seiten (Umami-API-Proxy)
- Admin-Panel Tab-Icons korrigiert (aus vorhandenem Phosphor-Sprite)
- users.real_name Spalte: Username öffentlich, echter Name privat und optional
- Registrierung: Label "Benutzername", Leerzeichen verboten, Profanity-Blockliste
- Datenschutzerklärung: GA-Abschnitt durch Umami-Text ersetzt

backend/media_utils.py

@@ -0,0 +1,99 @@
+import io
+import os
+import subprocess
+import tempfile
+from typing import Tuple
+
+_HEIC_EXTS  = {".heic", ".heif"}
+_VIDEO_EXTS = {".mov", ".avi", ".m4v"}
+
+
+def to_jpeg_if_heic(data: bytes, filename: str) -> Tuple[bytes, str]:
+    """Convert HEIC/HEIF to JPEG; return (data, ext) unchanged for all other types."""
+    ext = os.path.splitext(filename or "")[1].lower()
+    if ext not in _HEIC_EXTS:
+        return data, ext or ".jpg"
+    try:
+        import pillow_heif
+        pillow_heif.register_heif_opener()
+        from PIL import Image, ImageOps
+        img = Image.open(io.BytesIO(data))
+        img = ImageOps.exif_transpose(img)
+        img = img.convert("RGB")
+        buf = io.BytesIO()
+        img.save(buf, format="JPEG", quality=90)
+        return buf.getvalue(), ".jpg"
+    except Exception:
+        return data, ext
+
+
+def to_mp4_if_needed(data: bytes, filename: str) -> Tuple[bytes, str]:
+    """Convert MOV/AVI/M4V to H.264 MP4; return unchanged for MP4/WebM."""
+    ext = os.path.splitext(filename or "")[1].lower()
+    if ext not in _VIDEO_EXTS:
+        return data, ext or ".mp4"
+    src_path = dst_path = None
+    try:
+        with tempfile.NamedTemporaryFile(suffix=ext, delete=False) as src:
+            src.write(data)
+            src_path = src.name
+        dst_path = src_path[: -len(ext)] + ".mp4"
+        result = subprocess.run(
+            ["ffmpeg", "-i", src_path,
+             "-c:v", "libx264", "-preset", "fast", "-crf", "23",
+             "-c:a", "aac",
+             "-movflags", "+faststart",
+             "-y", dst_path],
+            capture_output=True, timeout=300,
+        )
+        if result.returncode == 0:
+            with open(dst_path, "rb") as f:
+                return f.read(), ".mp4"
+        return data, ext
+    except Exception:
+        return data, ext
+    finally:
+        for p in [src_path, dst_path]:
+            if p:
+                try:
+                    os.unlink(p)
+                except OSError:
+                    pass
+
+
+def convert_media(data: bytes, filename: str) -> Tuple[bytes, str]:
+    """Convert HEIC→JPEG and MOV/AVI/M4V→MP4; pass everything else through."""
+    ext = os.path.splitext(filename or "")[1].lower()
+    if ext in _HEIC_EXTS:
+        return to_jpeg_if_heic(data, filename)
+    if ext in _VIDEO_EXTS:
+        return to_mp4_if_needed(data, filename)
+    return data, ext or ".bin"
+
+
+def extract_video_thumb(video_path: str) -> str | None:
+    """Extract a frame at ~1s from video_path and save as <basename>_thumb.jpg.
+    Returns the thumb path on success, None on failure."""
+    base, _ = os.path.splitext(video_path)
+    thumb_path = base + "_thumb.jpg"
+    try:
+        result = subprocess.run(
+            ["ffmpeg", "-i", video_path,
+             "-ss", "1", "-vframes", "1",
+             "-q:v", "3", "-vf", "scale=480:-1",
+             "-y", thumb_path],
+            capture_output=True, timeout=30,
+        )
+        if result.returncode == 0 and os.path.exists(thumb_path):
+            return thumb_path
+        # Fallback: first frame (for videos shorter than 1s)
+        result2 = subprocess.run(
+            ["ffmpeg", "-i", video_path,
+             "-vframes", "1",
+             "-q:v", "3", "-vf", "scale=480:-1",
+             "-y", thumb_path],
+            capture_output=True, timeout=30,
+        )
+        return thumb_path if result2.returncode == 0 and os.path.exists(thumb_path) else None
+    except Exception:
+        return None