# HG changeset patch
# User James Bergstra <bergstrj@iro.umontreal.ca>
# Date 1305730342 14400
# Node ID 91a475ca9b6d586373d940e5f27af9074820cd08
# Parent  ddda8d93c162217426daae4e4dd7281c15e2c48f
image_tiling with better scaling for integer inputs

diff -r ddda8d93c162 -r 91a475ca9b6d pylearn/io/image_tiling.py
--- a/pylearn/io/image_tiling.py	Wed May 18 10:51:50 2011 -0400
+++ b/pylearn/io/image_tiling.py	Wed May 18 10:52:22 2011 -0400
@@ -100,6 +100,10 @@
         H, W = img_shape
         Hs, Ws = tile_spacing
 
+        out_scaling = 1
+        if output_pixel_vals and str(X.dtype).startswith('float'):
+            out_scaling = 255
+
         out_array = numpy.zeros(out_shape, dtype='uint8' if output_pixel_vals else X.dtype)
         for tile_row in xrange(tile_shape[0]):
             for tile_col in xrange(tile_shape[1]):
@@ -121,7 +125,7 @@
                         tile_row * (H+Hs):tile_row*(H+Hs)+H,
                         tile_col * (W+Ws):tile_col*(W+Ws)+W
                         ] \
-                        = this_img * (255 if output_pixel_vals else 1)
+                        = this_img * out_scaling
         return out_array