6668 fix hard-coded up_kernel_size in ViTAutoEnc (#6735)

Fixes #6668 .

Fix hard-coded `up_kernel_size` in `ViTAutoEnc` without changing the
network architecture.
### Types of changes
<!--- Put an `x` in all the boxes that apply, and remove the not
applicable items -->
- [x] Non-breaking change (fix or new feature that would not break
existing functionality).
- [ ] Breaking change (fix or new feature that would cause existing
functionality to change).
- [ ] New tests added to cover the changes.
- [ ] Integration tests passed locally by running `./runtests.sh -f -u
--net --coverage`.
- [ ] Quick tests passed locally by running `./runtests.sh --quick
--unittests --disttests`.
- [ ] In-line docstrings updated.
- [ ] Documentation updated, tested `make html` command in the `docs/`
folder.

---------

Signed-off-by: KumoLiu <yunl@nvidia.com>

Author: KumoLiu

monai/networks/nets/vitautoenc.py

@@ -11,6 +11,7 @@
 
 from __future__ import annotations
 
+import math
 from collections.abc import Sequence
 
 import torch
@@ -19,7 +20,7 @@
 from monai.networks.blocks.patchembedding import PatchEmbeddingBlock
 from monai.networks.blocks.transformerblock import TransformerBlock
 from monai.networks.layers import Conv
-from monai.utils import ensure_tuple_rep
+from monai.utils import ensure_tuple_rep, is_sqrt
 
 __all__ = ["ViTAutoEnc"]
 
@@ -78,9 +79,14 @@ def __init__(
         """
 
         super().__init__()
-
+        if not is_sqrt(patch_size):
+            raise ValueError(f"patch_size should be square number, got {patch_size}.")
         self.patch_size = ensure_tuple_rep(patch_size, spatial_dims)
+        self.img_size = ensure_tuple_rep(img_size, spatial_dims)
         self.spatial_dims = spatial_dims
+        for m, p in zip(self.img_size, self.patch_size):
+            if m % p != 0:
+                raise ValueError(f"patch_size={patch_size} should be divisible by img_size={img_size}.")
 
         self.patch_embedding = PatchEmbeddingBlock(
             in_channels=in_channels,
@@ -100,12 +106,12 @@ def __init__(
         )
         self.norm = nn.LayerNorm(hidden_size)
 
-        new_patch_size = [4] * self.spatial_dims
         conv_trans = Conv[Conv.CONVTRANS, self.spatial_dims]
         # self.conv3d_transpose* is to be compatible with existing 3d model weights.
-        self.conv3d_transpose = conv_trans(hidden_size, deconv_chns, kernel_size=new_patch_size, stride=new_patch_size)
+        up_kernel_size = [int(math.sqrt(i)) for i in self.patch_size]
+        self.conv3d_transpose = conv_trans(hidden_size, deconv_chns, kernel_size=up_kernel_size, stride=up_kernel_size)
         self.conv3d_transpose_1 = conv_trans(
-            in_channels=deconv_chns, out_channels=out_channels, kernel_size=new_patch_size, stride=new_patch_size
+            in_channels=deconv_chns, out_channels=out_channels, kernel_size=up_kernel_size, stride=up_kernel_size
         )
 
     def forward(self, x):

monai/utils/__init__.py

@@ -80,6 +80,7 @@
     is_module_ver_at_least,
     is_scalar,
     is_scalar_tensor,
+    is_sqrt,
     issequenceiterable,
     list_to_dict,
     path_to_uri,

monai/utils/misc.py

@@ -13,6 +13,7 @@
 
 import inspect
 import itertools
+import math
 import os
 import pprint
 import random
@@ -853,3 +854,13 @@ def run_cmd(cmd_list: list[str], **kwargs: Any) -> subprocess.CompletedProcess:
         output = str(e.stdout.decode(errors="replace"))
         errors = str(e.stderr.decode(errors="replace"))
         raise RuntimeError(f"subprocess call error {e.returncode}: {errors}, {output}.") from e
+
+
+def is_sqrt(num: Sequence[int] | int) -> bool:
+    """
+    Determine if the input is a square number or a squence of square numbers.
+    """
+    num = ensure_tuple(num)
+    sqrt_num = [int(math.sqrt(_num)) for _num in num]
+    ret = [_i * _j for _i, _j in zip(sqrt_num, sqrt_num)]
+    return ensure_tuple(ret) == num

tests/test_vitautoenc.py

@@ -49,7 +49,7 @@
         {
             "in_channels": 1,
             "img_size": (512, 512, 32),
-            "patch_size": (16, 16, 16),
+            "patch_size": (64, 64, 16),
             "hidden_size": 768,
             "mlp_dim": 3072,
             "num_layers": 4,
@@ -147,6 +147,19 @@ def test_ill_arg(self):
                 dropout_rate=0.3,
             )
 
+        with self.assertRaises(ValueError):
+            ViTAutoEnc(
+                in_channels=4,
+                img_size=(96, 96, 96),
+                patch_size=(9, 9, 9),
+                hidden_size=768,
+                mlp_dim=3072,
+                num_layers=12,
+                num_heads=12,
+                pos_embed="perc",
+                dropout_rate=0.3,
+            )
+
 
 if __name__ == "__main__":
     unittest.main()