diff --git a/scripts/auto_caption.py b/scripts/auto_caption.py
index 7833aef..4b3daf5 100644
--- a/scripts/auto_caption.py
+++ b/scripts/auto_caption.py
@@ -11,6 +11,7 @@ import asyncio
 import subprocess
 import numpy as np
 import io
+import aiofiles
 
 SIZE = 384
 BLIP_MODEL_URL = 'https://storage.googleapis.com/sfr-vision-language-research/BLIP/models/model_base_caption_capfilt_large.pth'
@@ -39,7 +40,7 @@ def get_parser(**parser_kwargs):
         nargs="?",
         const=True,
         default="filename",
-        help="'filename', 'json', or 'parquet'",
+        help="'filename', 'mrwho', 'txt', or 'caption'",
     ),
     parser.add_argument(
         "--nucleus",
@@ -115,7 +116,7 @@ async def main(opt):
     else:
         print(f"Model already cached to: {model_cache_path}")
 
-    blip_decoder = models.blip.blip_decoder(pretrained=model_cache_path, image_size=384, vit='base', med_config=config_path)
+    blip_decoder = models.blip.blip_decoder(pretrained=model_cache_path, image_size=SIZE, vit='base', med_config=config_path)
     blip_decoder.eval()
 
     print("loading model to cuda")
@@ -131,13 +132,13 @@ async def main(opt):
             caption = None
             file_ext = os.path.splitext(img_file_name)[1]
             if (file_ext in ext):
-                with open(img_file_name, "rb") as input_file:
+                async with aiofiles.open(img_file_name, "rb") as input_file:
                     print("working image: ", img_file_name)
 
-                    image = Image.open(input_file)
+                    image_bin = await input_file.read()
+                    image = Image.open(io.BytesIO(image_bin))
 
                     if not image.mode == "RGB":
-                        print("converting to RGB")
                         image = image.convert("RGB")
 
                     image = load_image(image, device=torch.device("cuda"))
@@ -150,14 +151,14 @@ async def main(opt):
 
                     caption = captions[0]
 
-                    input_file.seek(0)
-                    data = input_file.read()
-                    input_file.close()
-
                     if opt.format in ["mrwho","joepenna"]:
                         prefix = f"{i:05}@"
                         i += 1
                         caption = prefix+caption
+                    elif opt.format == "filename":
+                        postfix = f"_{i}"
+                        i += 1
+                        caption = caption+postfix
 
                     if opt.format in ["txt","text","caption"]:
                         out_base_name = os.path.splitext(os.path.basename(img_file_name))[0]
@@ -170,14 +171,14 @@ async def main(opt):
 
                     if opt.format in ["txt","text","caption"]:
                         print("writing caption to: ", out_file)
-                        with open(out_file, "w") as out_file:
-                            out_file.write(caption)
+                        async with aiofiles.open(out_file, "w") as out_file:
+                            await out_file.write(caption)
 
                     if opt.format in ["filename", "mrwho", "joepenna"]:
                         caption = caption.replace("/", "").replace("\\", "")  # must clean slashes using filename
                         out_file = get_out_file_name(opt.out_dir, caption, file_ext)
-                        with open(out_file, "wb") as out_file:
-                            out_file.write(data)
+                        async with aiofiles.open(out_file, "wb") as out_file:
+                            await out_file.write(image_bin)
                     elif opt.format == "json":
                         raise NotImplementedError
                     elif opt.format == "parquet":