[pycaffe] test coord_map

- test known mappings: conv-pool-deconv stack, ReLU and 1x1 conv
- test effects of padding
- test rectangular/anisotropic coordinate mapping, test N-D
- catch error cases: negative crop, scale mismatch, tops that are not
  spatially connected

python/caffe/test/test_coord_map.py

@@ -0,0 +1,192 @@
+import unittest
+
+import numpy as np
+import random
+
+import caffe
+from caffe import layers as L
+from caffe import params as P
+from caffe.coord_map import coord_map_from_to, crop
+
+
+def coord_net_spec(ks=3, stride=1, pad=0, pool=2, dstride=2, dpad=0):
+    """
+    Define net spec for simple conv-pool-deconv pattern common to all
+    coordinate mapping tests.
+    """
+    n = caffe.NetSpec()
+    n.data = L.Input(shape=dict(dim=[2, 1, 100, 100]))
+    n.aux = L.Input(shape=dict(dim=[2, 1, 20, 20]))
+    n.conv = L.Convolution(
+        n.data, num_output=10, kernel_size=ks, stride=stride, pad=pad)
+    n.pool = L.Pooling(
+        n.conv, pool=P.Pooling.MAX, kernel_size=pool, stride=pool, pad=0)
+    # for upsampling kernel size is 2x stride
+    try:
+        deconv_ks = [s*2 for s in dstride]
+    except:
+        deconv_ks = dstride*2
+    n.deconv = L.Deconvolution(
+        n.pool, num_output=10, kernel_size=deconv_ks, stride=dstride, pad=dpad)
+    return n
+
+
+class TestCoordMap(unittest.TestCase):
+    def setUp(self):
+        pass
+
+    def test_conv_pool_deconv(self):
+        """
+        Map through conv, pool, and deconv.
+        """
+        n = coord_net_spec()
+        # identity for 2x pool, 2x deconv
+        ax, a, b = coord_map_from_to(n.deconv, n.data)
+        self.assertEquals(ax, 1)
+        self.assertEquals(a, 1)
+        self.assertEquals(b, 0)
+        # shift-by-one for 4x pool, 4x deconv
+        n = coord_net_spec(pool=4, dstride=4)
+        ax, a, b = coord_map_from_to(n.deconv, n.data)
+        self.assertEquals(ax, 1)
+        self.assertEquals(a, 1)
+        self.assertEquals(b, -1)
+
+    def test_pass(self):
+        """
+        A pass-through layer (ReLU) and conv (1x1, stride 1, pad 0)
+        both do identity mapping.
+        """
+        n = coord_net_spec()
+        ax, a, b = coord_map_from_to(n.deconv, n.data)
+        n.relu = L.ReLU(n.deconv)
+        n.conv1x1 = L.Convolution(
+            n.relu, num_output=10, kernel_size=1, stride=1, pad=0)
+        for top in [n.relu, n.conv1x1]:
+            ax_pass, a_pass, b_pass = coord_map_from_to(top, n.data)
+            self.assertEquals(ax, ax_pass)
+            self.assertEquals(a, a_pass)
+            self.assertEquals(b, b_pass)
+
+    def test_padding(self):
+        """
+        Padding conv adds offset while padding deconv subtracts offset.
+        """
+        n = coord_net_spec()
+        ax, a, b = coord_map_from_to(n.deconv, n.data)
+        pad = random.randint(0, 10)
+        # conv padding
+        n = coord_net_spec(pad=pad)
+        _, a_pad, b_pad = coord_map_from_to(n.deconv, n.data)
+        self.assertEquals(a, a_pad)
+        self.assertEquals(b - pad, b_pad)
+        # deconv padding
+        n = coord_net_spec(dpad=pad)
+        _, a_pad, b_pad = coord_map_from_to(n.deconv, n.data)
+        self.assertEquals(a, a_pad)
+        self.assertEquals(b + pad, b_pad)
+        # pad both to cancel out
+        n = coord_net_spec(pad=pad, dpad=pad)
+        _, a_pad, b_pad = coord_map_from_to(n.deconv, n.data)
+        self.assertEquals(a, a_pad)
+        self.assertEquals(b, b_pad)
+
+    def test_multi_conv(self):
+        """
+        Multiple bottoms/tops of a layer are identically mapped.
+        """
+        n = coord_net_spec()
+        # multi bottom/top
+        n.conv_data, n.conv_aux = L.Convolution(
+            n.data, n.aux, ntop=2, num_output=10, kernel_size=5, stride=2,
+            pad=0)
+        ax1, a1, b1 = coord_map_from_to(n.conv_data, n.data)
+        ax2, a2, b2 = coord_map_from_to(n.conv_aux, n.aux)
+        self.assertEquals(ax1, ax2)
+        self.assertEquals(a1, a2)
+        self.assertEquals(b1, b2)
+
+    def test_rect(self):
+        """
+        Anisotropic mapping is equivalent to its isotropic parts.
+        """
+        n3x3 = coord_net_spec(ks=3, stride=1, pad=0)
+        n5x5 = coord_net_spec(ks=5, stride=2, pad=10)
+        n3x5 = coord_net_spec(ks=[3, 5], stride=[1, 2], pad=[0, 10])
+        ax_3x3, a_3x3, b_3x3 = coord_map_from_to(n3x3.deconv, n3x3.data)
+        ax_5x5, a_5x5, b_5x5 = coord_map_from_to(n5x5.deconv, n5x5.data)
+        ax_3x5, a_3x5, b_3x5 = coord_map_from_to(n3x5.deconv, n3x5.data)
+        self.assertTrue(ax_3x3 == ax_5x5 == ax_3x5)
+        self.assertEquals(a_3x3, a_3x5[0])
+        self.assertEquals(b_3x3, b_3x5[0])
+        self.assertEquals(a_5x5, a_3x5[1])
+        self.assertEquals(b_5x5, b_3x5[1])
+
+    def test_nd_conv(self):
+        """
+        ND conv maps the same way in more dimensions.
+        """
+        n = caffe.NetSpec()
+        # define data with 3 spatial dimensions, otherwise the same net
+        n.data = L.Input(shape=dict(dim=[2, 3, 100, 100, 100]))
+        n.conv = L.Convolution(
+            n.data, num_output=10, kernel_size=[3, 3, 3], stride=[1, 1, 1],
+            pad=[0, 1, 2])
+        n.pool = L.Pooling(
+            n.conv, pool=P.Pooling.MAX, kernel_size=2, stride=2, pad=0)
+        n.deconv = L.Deconvolution(
+            n.pool, num_output=10, kernel_size=4, stride=2, pad=0)
+        ax, a, b = coord_map_from_to(n.deconv, n.data)
+        self.assertEquals(ax, 1)
+        self.assertTrue(len(a) == len(b))
+        self.assertTrue(np.all(a == 1))
+        self.assertEquals(b[0] - 1, b[1])
+        self.assertEquals(b[1] - 1, b[2])
+
+    def test_crop_of_crop(self):
+        """
+        Map coordinates through Crop layer:
+        crop an already-cropped output to the input and check change in offset.
+        """
+        n = coord_net_spec()
+        offset = random.randint(0, 10)
+        ax, a, b = coord_map_from_to(n.deconv, n.data)
+        n.crop = L.Crop(n.deconv, n.data, axis=2, offset=offset)
+        ax_crop, a_crop, b_crop = coord_map_from_to(n.crop, n.data)
+        self.assertEquals(ax, ax_crop)
+        self.assertEquals(a, a_crop)
+        self.assertEquals(b + offset, b_crop)
+
+    def test_crop_helper(self):
+        """
+        Define Crop layer by crop().
+        """
+        n = coord_net_spec()
+        crop(n.deconv, n.data)
+
+    def test_catch_unconnected(self):
+        """
+        Catch mapping spatially unconnected tops.
+        """
+        n = coord_net_spec()
+        n.ip = L.InnerProduct(n.deconv, num_output=10)
+        with self.assertRaises(RuntimeError):
+            coord_map_from_to(n.ip, n.data)
+
+    def test_catch_scale_mismatch(self):
+        """
+        Catch incompatible scales, such as when the top to be cropped
+        is mapped to a differently strided reference top.
+        """
+        n = coord_net_spec(pool=3, dstride=2)  # pool 3x but deconv 2x
+        with self.assertRaises(AssertionError):
+            crop(n.deconv, n.data)
+
+    def test_catch_negative_crop(self):
+        """
+        Catch impossible offsets, such as when the top to be cropped
+        is mapped to a larger reference top.
+        """
+        n = coord_net_spec(dpad=10)  # make output smaller than input
+        with self.assertRaises(AssertionError):
+            crop(n.deconv, n.data)