Update keras/src/backend/tensorflow/image.py

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: pctablet505

keras/src/backend/tensorflow/image.py

@@ -711,8 +711,9 @@ def process_coordinates(coords, size):
 
         if fill_mode == "constant":
             all_valid = tf.reduce_all(validities, axis=0)
-            fill_value_typed = tf.cast(fill_value, weights[0].dtype)
-            gathered = tf.where(all_valid, gathered, fill_value_typed)
+        dtype = weights[0].dtype
+        fill_value_typed = tf.cast(fill_value, dtype)
+        gathered = tf.where(all_valid, gathered, fill_value_typed)
 
         outputs.append(functools.reduce(operator.mul, weights) * gathered)