feat: add checkpoint download script for Windows

README.md

@@ -36,7 +36,8 @@ First, we need to download a model checkpoint. All the model checkpoints can be
 
 ```bash
 cd checkpoints
-./download_ckpts.sh
+./download_ckpts.sh # on Unix
+./download_ckpts.ps1 # on Windows
 ```
 
 or individually from:

checkpoints/download_ckpts.ps1

@@ -0,0 +1,43 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+
+# This source code is licensed under the license found in the
+# LICENSE file in the root directory of this source tree.
+
+# Define the URLs for the checkpoints
+$baseUrl = "https://dl.fbaipublicfiles.com/segment_anything_2/072824/"
+$sam2_hiera_t_url = "${baseUrl}sam2_hiera_tiny.pt"
+$sam2_hiera_s_url = "${baseUrl}sam2_hiera_small.pt"
+$sam2_hiera_b_plus_url = "${baseUrl}sam2_hiera_base_plus.pt"
+$sam2_hiera_l_url = "${baseUrl}sam2_hiera_large.pt"
+
+# Function to download files
+function Get-File {
+    param (
+        [string]$url,
+        [string]$filename
+    )
+    try {
+        Invoke-WebRequest -Uri $url -OutFile $filename
+        Write-Host "$filename downloaded successfully."
+    }
+    catch {
+        Write-Host "Failed to download checkpoint from $url"
+        exit 1
+    }
+}
+
+# Download each of the four checkpoints
+Write-Host "Downloading sam2_hiera_tiny.pt checkpoint..."
+Download-File -url $sam2_hiera_t_url -filename "sam2_hiera_tiny.pt"
+
+Write-Host "Downloading sam2_hiera_small.pt checkpoint..."
+Download-File -url $sam2_hiera_s_url -filename "sam2_hiera_small.pt"
+
+Write-Host "Downloading sam2_hiera_base_plus.pt checkpoint..."
+Download-File -url $sam2_hiera_b_plus_url -filename "sam2_hiera_base_plus.pt"
+
+Write-Host "Downloading sam2_hiera_large.pt checkpoint..."
+Download-File -url $sam2_hiera_l_url -filename "sam2_hiera_large.pt"
+
+Write-Host "All checkpoints are downloaded successfully."