Rename GetImageNumChannels and update references

Renamed the method `GetImageNumChannels` to `get_image_num_channels` in `Functional.cs`. Added a summary documentation comment to the `get_image_num_channels` method, detailing its purpose, parameter, and return value. Updated the call to this method in `Normalize.cs` to reflect the new name.

Author: AhmedZero

src/TorchVision/Functional.cs

@@ -37,7 +37,12 @@ private static bool AssertTensorImage(Tensor img)
                     return true;
                 }
 
-                public static long GetImageNumChannels(Tensor img)
+                /// <summary>
+                /// Returns the number of channels of an image.
+                /// </summary>
+                /// <param name="img">(Tensor) – The image to be checked.</param>
+                /// <returns>The number of channels.</returns>
+                public static long get_image_num_channels(Tensor img)
                 {
                     AssertTensorImage(img);
                     var ndim_ = img.ndim;

src/TorchVision/Normalize.cs

@@ -23,7 +23,7 @@ internal Normalize(double[] means, double[] stdevs,bool inplace = false)
 
             public Tensor call(Tensor input)
             {
-                var expectedChannels = transforms.functional.GetImageNumChannels(input);
+                var expectedChannels = transforms.functional.get_image_num_channels(input);
                 if (expectedChannels != means.Length)
                     throw new ArgumentException("The number of channels is not equal to the number of means and standard deviations");
                 return transforms.functional.normalize(input, means, stdevs, inplace);