add cosine decay

configs/rec/rec_icdar15_train.yml

@@ -41,3 +41,7 @@ Optimizer:
   base_lr: 0.0005
   beta1: 0.9
   beta2: 0.999
+  decay:
+    function: cosine_decay
+    step_each_epoch: 20
+    total_epoch: 1000

ppocr/optimizer.py

@@ -28,6 +28,16 @@ def AdamDecay(params, parameter_list=None):
     base_lr = params['base_lr']
     beta1 = params['beta1']
     beta2 = params['beta2']
+    if 'decay' in params:
+        params = params['decay']
+        decay_mode = params['function']
+        step_each_epoch = params['step_each_epoch']
+        total_epoch = params['total_epoch']
+        if decay_mode == "cosine_decay":
+            base_lr = fluid.layers.cosine_decay(
+                learning_rate=base_lr,
+                step_each_epoch=step_each_epoch,
+                epochs=total_epoch)
     optimizer = fluid.optimizer.Adam(
         learning_rate=base_lr,
         beta1=beta1,