never fall through to HEVC origin when H264 FLV exists (2x transcode saturated cpu-basic)

youtube_manager.py

@@ -150,9 +150,13 @@ class ManagedYouTube:
             supported=[c for c in sources if any(k in _cod(c) for k in ('h264','avc','h265','hevc'))] or list(sources)
             prefer=str(os.getenv('YOUTUBE_PREFER_H264','1')).strip().lower() in ('1','on','true','yes')
             if prefer and os.getenv('YOUTUBE_SEND_MODE','auto').strip().lower() in ('auto','copy'):
-                supported=sorted(supported,key=lambda c:(
-                    0 if any(k in _cod(c) for k in ('h264','avc')) else 1,
-                    0 if str(c.get('media') or '')=='flv' else 1))
+                h264=[c for c in supported if any(k in _cod(c) for k in ('h264','avc'))]
+                # Measured: falling through to origin HEVC then fixed720 pegged 2-core
+                # quota at 99–101% (a3dam_111). H264 hd copy of the same room was ~few % CPU.
+                if h264:
+                    supported=sorted(h264, key=lambda c: 0 if str(c.get('media') or '')=='flv' else 1)
+                else:
+                    supported=sorted(supported, key=lambda c: 0 if str(c.get('media') or '')=='flv' else 1)
             out=supported
         else:
             raise RuntimeError('YOUTUBE_VIDEO_MODE يجب أن يكون original أو h264')