added documentation about the new Cityscapes dataset download policy

Author: taesungp

datasets/download_cyclegan_dataset.sh

@@ -5,6 +5,12 @@ if [[ $FILE != "ae_photos" && $FILE != "apple2orange" && $FILE != "summer2winter
     exit 1
 fi
 
+if [[ $FILE == "cityscapes" ]]; then
+    echo "Due to license issue, we cannot provide the Cityscapes dataset from our repository. Please download the Cityscapes dataset from https://cityscapes-dataset.com, and use the script ./datasets/prepare_cityscapes_dataset.py."
+    echo "You need to download gtFine_trainvaltest.zip and leftImg8bit_trainvaltest.zip. For further instruction, please read ./datasets/prepare_cityscapes_dataset.py"
+    exit 1
+fi
+
 echo "Specified [$FILE]"
 URL=https://people.eecs.berkeley.edu/~taesung_park/CycleGAN/datasets/$FILE.zip
 ZIP_FILE=./datasets/$FILE.zip

datasets/download_pix2pix_dataset.sh

@@ -5,6 +5,12 @@ if [[ $FILE != "cityscapes" && $FILE != "night2day" && $FILE != "edges2handbags"
   exit 1
 fi
 
+if [[ $FILE == "cityscapes" ]]; then
+    echo "Due to license issue, we cannot provide the Cityscapes dataset from our repository. Please download the Cityscapes dataset from https://cityscapes-dataset.com, and use the script ./datasets/prepare_cityscapes_dataset.py."
+    echo "You need to download gtFine_trainvaltest.zip and leftImg8bit_trainvaltest.zip. For further instruction, please read ./datasets/prepare_cityscapes_dataset.py"
+    exit 1
+fi
+
 echo "Specified [$FILE]"
 
 URL=http://efrosgans.eecs.berkeley.edu/pix2pix/datasets/$FILE.tar.gz

docs/datasets.md

@@ -6,7 +6,7 @@ Download the CycleGAN datasets using the following script. Some of the datasets
 bash ./datasets/download_cyclegan_dataset.sh dataset_name
 ```
 - `facades`: 400 images from the [CMP Facades dataset](http://cmp.felk.cvut.cz/~tylecr1/facade). [[Citation](../datasets/bibtex/facades.tex)]
-- `cityscapes`: 2975 images from the [Cityscapes training set](https://www.cityscapes-dataset.com). [[Citation](../datasets/bibtex/cityscapes.tex)]
+- `cityscapes`: 2975 images from the [Cityscapes training set](https://www.cityscapes-dataset.com). [[Citation](../datasets/bibtex/cityscapes.tex)]. Note: Due to license issue, we cannot directly provide the Cityscapes dataset. Please download the Cityscapes dataset from [https://cityscapes-dataset.com](https://cityscapes-dataset.com)  and use the script `./datasets/prepare_cityscapes_dataset.py`.
 - `maps`: 1096 training images scraped from Google Maps.
 - `horse2zebra`: 939 horse images and 1177 zebra images downloaded from [ImageNet](http://www.image-net.org) using keywords `wild horse` and `zebra`
 - `apple2orange`: 996 apple images and 1020 orange images downloaded from [ImageNet](http://www.image-net.org) using keywords `apple` and `navel orange`.