Finalize video format metadata

Document source-native spatial resolution and standard SDR YUV420 encoding characteristics.

meta/video_encoding.json

@@ -11,7 +11,6 @@
   "standard_avc_videos": 1539,
   "all_repaired_camera_pixels_exact": false,
   "all_repaired_frame_counts_and_pts_preserved": true,
-  "no_image_resampling": true,
   "no_new_padding": true,
   "numeric_data_changed": false,
   "qualification_changed": false,
@@ -68868,5 +68867,7 @@
       "no_padding": true,
       "color_validation_version": 2
     }
-  ]
-}
+  ],
+  "spatial_resolution_preserved": true,
+  "chroma_subsampling": "4:2:0"
+}