create image output directory if it doesn't exist

README.md

@@ -86,6 +86,29 @@ If you don't like this change, just copy over the file
 ldm/modules/encoders/modules.py from the CompVis/stable-diffusion
 repository.
 
+In addition, I have found that the Kornia library needs to do a
+one-time download of its own. On a non-internet connected system, you
+may see an error message like this one when running dream.py for the
+first time
+
+~~~~
+Downloading: "https://github.com/DagnyT/hardnet/raw/master/pretrained/train_liberty_with_aug/checkpoint_liberty_with_aug.pth" to /u/lstein/.cache/torch/hub/checkpoints/checkpoint_liberty_with_aug.pth
+Traceback (most recent call last):
+  File "/u/lstein/.conda/envs/ldm/lib/python3.8/urllib/request.py", line 1350, in do_open
+    h.request(req.get_method(), req.selector, req.data, headers,
+  File "/u/lstein/.conda/envs/ldm/lib/python3.8/http/client.py", line 1255, in request
+...
+~~~~
+
+The fix is to log into an internet-connected machine and manually
+download the file into the required location. On my system, the incantation was:
+
+~~~~
+(ldm) ~/stable-diffusion$ mkdir -p /u/lstein/.cache/torch/hub/checkpoints/
+(ldm) ~/stable-diffusion$ wget https://github.com/DagnyT/hardnet/raw/master/pretrained/train_liberty_with_aug/checkpoint_liberty_with_aug.pth \
+                            -O /u/lstein/.cache/torch/hub/checkpoints/checkpoint_liberty_with_aug.pth
+~~~~
+
 ## Minor fixes
 
 I added the requirement for torchmetrics to environment.yaml.

scripts/dream.py

@@ -4,7 +4,7 @@ import readline
 import argparse
 import shlex
 import atexit
-from os import path
+import os
 
 def main():
     arg_parser = create_argv_parser()
@@ -41,6 +41,10 @@ def main():
               weights=weights,
               config=config)
 
+    # make sure the output directory exists
+    if not os.path.exists(opt.outdir):
+        os.makedirs(opt.outdir)
+        
     # gets rid of annoying messages about random seed
     logging.getLogger("pytorch_lightning").setLevel(logging.ERROR)
 
@@ -48,7 +52,7 @@ def main():
     t2i.load_model()
     print("\n* Initialization done! Awaiting your command...")
 
-    log_path   = path.join(opt.outdir,"dream_log.txt")
+    log_path   = os.path.join(opt.outdir,"dream_log.txt")
     with open(log_path,'a') as log:
         cmd_parser = create_cmd_parser()
         main_loop(t2i,cmd_parser,log)
@@ -132,7 +136,7 @@ def create_cmd_parser():
     return parser
 
 def load_history():
-    histfile = path.join(path.expanduser('~'),".dream_history")
+    histfile = os.path.join(os.path.expanduser('~'),".dream_history")
     try:
         readline.read_history_file(histfile)
         readline.set_history_length(1000)