fix tiling, rope precision and weights

mlx_video/models/ltx/video_vae/tiling.py

@@ -160,6 +160,9 @@ class TilingConfig:
     ) -> Optional["TilingConfig"]:
         """Automatically determine tiling config based on video dimensions.
 
+        Uses PyTorch's default tiling (512px spatial, 64f temporal) which provides
+        enough context for CausalConv3d and sufficient overlap for clean blending.
+
         Args:
             height: Video height in pixels
             width: Video width in pixels
@@ -176,37 +179,17 @@ class TilingConfig:
         if not needs_spatial and not needs_temporal:
             return None
 
-        # Estimate memory requirement (rough heuristic)
-        # Output size in bytes (float32): B * 3 * F * H * W * 4
-        estimated_output_gb = (3 * num_frames * height * width * 4) / (1024**3)
-
-        # For very large videos, use aggressive tiling
-        if estimated_output_gb > 2.0 or (height * width > 768 * 1024 and num_frames > 100):
-            return cls.aggressive()
-
+        # Use the same defaults as PyTorch (512px spatial, 64f temporal).
+        # Smaller tiles cause quality degradation because CausalConv3d needs
+        # sufficient temporal context and overlap for clean blending.
         spatial_config = None
         temporal_config = None
 
         if needs_spatial:
-            # Choose tile size based on resolution
-            max_dim = max(height, width)
-            if max_dim > 1024:
-                tile_size = 384  # Smaller tiles for very large resolutions
-            elif max_dim > 768:
-                tile_size = 512
-            else:
-                tile_size = 384
-            spatial_config = SpatialTilingConfig(tile_size_in_pixels=tile_size, tile_overlap_in_pixels=64)
+            spatial_config = SpatialTilingConfig(tile_size_in_pixels=512, tile_overlap_in_pixels=64)
 
         if needs_temporal:
-            # Choose tile size based on frame count
-            if num_frames > 200:
-                tile_size, overlap = 32, 8  # Aggressive for very long videos
-            elif num_frames > 100:
-                tile_size, overlap = 48, 16
-            else:
-                tile_size, overlap = 64, 24
-            temporal_config = TemporalTilingConfig(tile_size_in_frames=tile_size, tile_overlap_in_frames=overlap)
+            temporal_config = TemporalTilingConfig(tile_size_in_frames=64, tile_overlap_in_frames=24)
 
         return cls(spatial_config=spatial_config, temporal_config=temporal_config)