Issue #768: Support passing none to resize and crop image

gradio/components.py

@@ -1111,7 +1111,7 @@ def __init__(
         """
         Parameters:
         default_value(str): A path or URL for the default value that Image component is going to take.
-        shape (Tuple[int, int]): (width, height) shape to crop and resize image to; if None, matches input image size.
+        shape (Tuple[int, int]): (width, height) shape to crop and resize image to; if None, matches input image size. Pass None for either width or height to only crop and resize the other.
         image_mode (str): "RGB" if color, or "L" if black and white.
         invert_colors (bool): whether to invert the image as a preprocessing step.
         source (str): Source of image. "upload" creates a box where user can drop an image file, "webcam" allows user to take snapshot from their webcam, "canvas" defaults to a white image that can be edited and drawn upon with tools.

gradio/processing_utils.py

@@ -97,7 +97,8 @@ def resize_and_crop(img, size, crop_type="center"):
     """
     Resize and crop an image to fit the specified size.
     args:
-        size: `(width, height)` tuple.
+        size: `(width, height)` tuple. Pass `None` for either width or height
+        to only crop and resize the other.
         crop_type: can be 'top', 'middle' or 'bottom', depending on this
             value, the image will cropped getting the 'top/left', 'middle' or
             'bottom/right' of the image to fit the size.
@@ -110,7 +111,13 @@ def resize_and_crop(img, size, crop_type="center"):
         center = (0.5, 0.5)
     else:
         raise ValueError
-    return ImageOps.fit(img, size, centering=center)
+
+    resize = list(size)
+    if size[0] is None:
+        resize[0] = img.size[0]
+    if size[1] is None:
+        resize[1] = img.size[1]
+    return ImageOps.fit(img, resize, centering=center)
 
 
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