add stargan pretrain model (#366)

configs/starganv2_celeba_hq.yaml

@@ -24,7 +24,7 @@ model:
     num_domains: *NUM_DOMAINS
   fan:
     name: FAN
-    fname_pretrained: models/stargan-v2/wing.pdparams
+    fname_pretrained: None
   discriminator:
     name: StarGANv2Discriminator
     img_size: *IMAGE_SIZE

ppgan/models/generators/generator_starganv2.py

@@ -9,6 +9,9 @@ import math
 
 from ppgan.modules.wing import CoordConvTh, ConvBlock, HourGlass, preprocess
 
+from ppgan.utils.download import get_path_from_url
+
+FAN_WEIGHT_URL = "https://paddlegan.bj.bcebos.com/models/wing.pdparams"
 
 class AvgPool2D(nn.Layer):
     """
@@ -298,6 +301,9 @@ class FAN(nn.Layer):
 
         if fname_pretrained is not None:
             self.load_pretrained_weights(fname_pretrained)
+        else:
+            weight_path = get_path_from_url(FAN_WEIGHT_URL)
+            self.load_pretrained_weights(weight_path)
 
     def load_pretrained_weights(self, fname):
         import pickle