Fix: Add missing imports and URL image loading in example code

## Description

This PR fixes runtime errors in the example code of the model card.

## Changes

- Added missing imports:
import numpy as np
import torch
import torch.nn.functional as F
import requests
from io import BytesIO

- Defined missing variable:
model_input_size = [1024, 1024]

- Replaced Image.open(image_path) with code that properly loads images from a URL:
response = requests.get(image_path)
orig_image = Image.open(BytesIO(response.content))

## Testing
The code has been successfully tested and runs without error.

## Note
This contribution is part of an ongoing research initiative to systematically identify and correct faulty example code in Hugging Face Model Cards.
We would appreciate a timely review and integration of this patch to support code reliability and enhance reproducibility for downstream users.

README.md

@@ -124,6 +124,13 @@ pillow_image = pipe(image_path) # applies mask on input and returns a pillow ima
 
 Or load the model 
 ```python
+import numpy as np
+import torch
+import torch.nn.functional as F
+import requests
+from io import BytesIO
+from PIL import Image
+from skimage import io
 from transformers import AutoModelForImageSegmentation
 from torchvision.transforms.functional import normalize
 model = AutoModelForImageSegmentation.from_pretrained("briaai/RMBG-1.4",trust_remote_code=True)
@@ -153,6 +160,7 @@ model.to(device)
 image_path = "https://farm5.staticflickr.com/4007/4322154488_997e69e4cf_z.jpg"
 orig_im = io.imread(image_path)
 orig_im_size = orig_im.shape[0:2]
+model_input_size = [1024, 1024]
 image = preprocess_image(orig_im, model_input_size).to(device)
 
 # inference 
@@ -163,7 +171,8 @@ result_image = postprocess_image(result[0][0], orig_im_size)
 
 # save result
 pil_mask_im = Image.fromarray(result_image)
-orig_image = Image.open(image_path)
+response = requests.get(image_path)
+orig_image = Image.open(BytesIO(response.content))
 no_bg_image = orig_image.copy()
 no_bg_image.putalpha(pil_mask_im)
 ```