From c13005fd422b20dcd11774e9fff46370887218e4 Mon Sep 17 00:00:00 2001
From: Gianluca Gippetto <gianluca.gippetto@gmail.com>
Date: Fri, 24 Sep 2021 03:42:20 +0200
Subject: [PATCH] In Compose, replace lambda function with named function
 (#151)

This prevents the following error on Windows (when using
a multi-process DataLoader, for example):

AttributeError: Can't pickle local object '_transform.<locals>.<lambda>'
---
 clip/clip.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/clip/clip.py b/clip/clip.py
index 6ce5565..9d6f4d6 100644
--- a/clip/clip.py
+++ b/clip/clip.py
@@ -68,11 +68,15 @@ def _download(url: str, root: str):
     return download_target
 
 
+def _convert_image_to_rgb(image):
+    return image.convert("RGB")
+
+
 def _transform(n_px):
     return Compose([
         Resize(n_px, interpolation=BICUBIC),
         CenterCrop(n_px),
-        lambda image: image.convert("RGB"),
+        _convert_image_to_rgb,
         ToTensor(),
         Normalize((0.48145466, 0.4578275, 0.40821073), (0.26862954, 0.26130258, 0.27577711)),
     ])