From 45800292de64f5e6a009399604e2761167bb3365 Mon Sep 17 00:00:00 2001
From: Emile Anclin <emile@cbien.com>
Date: Fri, 27 May 2016 14:56:38 +0200
Subject: [PATCH] strongly improved network stripping

---
 ocrolib/lstm.py | 23 +++++++++++++++++++++--
 ocropus-rtrain  |  3 ++-
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/ocrolib/lstm.py b/ocrolib/lstm.py
index 8380b994..cfc0d874 100644
--- a/ocrolib/lstm.py
+++ b/ocrolib/lstm.py
@@ -292,6 +292,14 @@ def __init__(self,Nh,No,initial_range=initial_range,rand=rand):
         self.No = No
         self.W2 = randu(No,Nh+1)*initial_range
         self.DW2 = zeros((No,Nh+1))
+    def postLoad(self):
+        self.DW2 = zeros(self.W2.shape)
+
+    def preSave(self):
+        for var in ('state', 'DW2'):
+            if hasattr(self, var):
+                delattr(self, var)
+
     def ninputs(self):
         return self.Nh
     def noutputs(self):
@@ -596,6 +604,12 @@ def walk(self):
         yield self
         for sub in self.nets:
             for x in sub.walk(): yield x
+    def preSave(self):
+        self.dstats = defaultdict(list)  # reset
+        for delta in ('deltas', 'ldeltas'):
+            if hasattr(self, delta):
+                delattr(self, delta)
+
     def ninputs(self):
         return self.nets[0].ninputs()
     def noutputs(self):
@@ -859,11 +873,16 @@ def __init__(self,ninput,nstates,noutput=-1,codec=None,normalize=normalize_nfkc)
         self.clear_log()
     def walk(self):
         for x in self.lstm.walk(): yield x
-    def clear_log(self):
+    def clear_log(self, deallocate_tempvars=False):
         self.command_log = []
         self.error_log = []
         self.cerror_log = []
         self.key_log = []
+        if deallocate_tempvars:
+            for attrname in ('outputs', 'targets', 'aligned'):
+                if hasattr(self, attrname):
+                    delattr(self, attrname)
+
     def __setstate__(self,state):
         self.__dict__.update(state)
         self.upgrade()
@@ -874,7 +893,7 @@ def upgrade(self):
         if "cerror_log" not in dir(self): self.cerror_log = []
         if "key_log" not in dir(self): self.key_log = []
     def info(self):
-        self.net.info()
+        self.lstm.info()
     def setLearningRate(self,r,momentum=0.9):
         self.lstm.setLearningRate(r,momentum)
     def predictSequence(self,xs):
diff --git a/ocropus-rtrain b/ocropus-rtrain
index f84bc41e..e3ae2491 100755
--- a/ocropus-rtrain
+++ b/ocropus-rtrain
@@ -156,7 +156,8 @@ def save_lstm(fname,network):
         network.lstm.save(fname)
     else:
         if args.strip:
-            network.clear_log()
+            print yellow('saving stripped network (without temporary variables)...')
+            network.clear_log(deallocate_tempvars=True)
             for x in network.walk(): x.preSave()
         ocrolib.save_object(fname,network)
         if args.strip: