From 66d24bd5f2f5ac68b2ac3ef3759a715efeaede8e Mon Sep 17 00:00:00 2001
From: Jonathan L Long <jonlong@cs.berkeley.edu>
Date: Thu, 15 Jan 2015 01:27:42 -0800
Subject: [PATCH] [pycaffe] rough-hewn net specification

---
 python/caffe/__init__.py |  1 +
 python/caffe/layers.py   | 95 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 96 insertions(+)
 create mode 100644 python/caffe/layers.py

diff --git a/python/caffe/__init__.py b/python/caffe/__init__.py
index 37e8956da4f..b456ea9b287 100644
--- a/python/caffe/__init__.py
+++ b/python/caffe/__init__.py
@@ -3,4 +3,5 @@
 from .proto.caffe_pb2 import TRAIN, TEST
 from .classifier import Classifier
 from .detector import Detector
+from .layers import layers, params, to_proto
 import io
diff --git a/python/caffe/layers.py b/python/caffe/layers.py
new file mode 100644
index 00000000000..5c44936251f
--- /dev/null
+++ b/python/caffe/layers.py
@@ -0,0 +1,95 @@
+from collections import OrderedDict
+import re
+
+from .proto import caffe_pb2
+from google import protobuf
+
+def uncamel(s):
+    """Convert CamelCase to underscore_case."""
+
+    return re.sub('(?!^)([A-Z])(?=[^A-Z])', r'_\1', s).lower()
+
+def assign_proto(proto, name, val):
+    if isinstance(val, list):
+        getattr(proto, name).extend(val)
+    elif isinstance(val, dict):
+        for k, v in val.iteritems():
+            assign_proto(getattr(proto, name), k, v)
+    else:
+        setattr(proto, name, val)
+
+def to_proto(tops, names):
+    if not isinstance(tops, tuple):
+        tops = (tops,)
+    layers = OrderedDict()
+    for top in tops:
+        top.fn._to_proto(layers, names)
+
+    net = caffe_pb2.NetParameter()
+    net.layer.extend(layers.values())
+    return net
+
+class Top:
+    def __init__(self, fn, n):
+        self.fn = fn
+        self.n = n
+
+class Function:
+    def __init__(self, type_name, inputs, params):
+        self.type_name = type_name
+        self.inputs = inputs
+        self.params = params
+        self.ntop = self.params.get('ntop', 1)
+        if 'ntop' in self.params:
+            del self.params['ntop']
+        self.in_place = self.params.get('in_place', False)
+        if 'in_place' in self.params:
+            del self.params['in_place']
+        self.tops = tuple(Top(self, n) for n in range(self.ntop))
+
+    def _to_proto(self, layers, names):
+        bottom_names = []
+        for inp in self.inputs:
+            if inp.fn not in layers:
+                inp.fn._to_proto(layers, names)
+            bottom_names.append(layers[inp.fn].top[inp.n])
+        layer = caffe_pb2.LayerParameter()
+        layer.type = self.type_name
+        layer.bottom.extend(bottom_names)
+
+        if self.in_place:
+            layer.top.extend(layer.bottom)
+            layer.name = names[self.tops[0]]
+        else:
+            for top in self.tops:
+                layer.top.append(names[top])
+            layer.name = layer.top[0]
+
+        for k, v in self.params.iteritems():
+            # special case to handle generic *params
+            if k.endswith('param'):
+                assign_proto(layer, k, v)
+            else:
+                assign_proto(getattr(layer, uncamel(self.type_name) + '_param'), k, v)
+
+        layers[self] = layer
+
+class Layers:
+    def __getattr__(self, name):
+        def layer_fn(*args, **kwargs):
+            fn = Function(name, args, kwargs)
+            if fn.ntop == 1:
+                return fn.tops[0]
+            else:
+                return fn.tops
+        return layer_fn
+
+class Parameters:
+    def __getattr__(self, name):
+       class Param:
+            def __getattr__(self, param_name):
+                return getattr(getattr(caffe_pb2, name + 'Parameter'), param_name)
+       return Param()
+
+layers = Layers()
+params = Parameters()