From f7480d243356f599357a30a9bb74e7253f0542cf Mon Sep 17 00:00:00 2001
From: Luis Ibanez <luis.ibanez@kitware.com>
Date: Mon, 4 Oct 2010 12:41:48 -0400
Subject: [PATCH] Fixed bug when images is smaller than 64x64.

Now we compute the proper number of resolution levels to use when
an images has size smaller than 64x64 pixels.

Change-Id: I27b4d784c4416b88a8536eff44b285b3b9b2fdd6
---
 Code/Review/itkJPEG2000ImageIO.cxx | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/Code/Review/itkJPEG2000ImageIO.cxx b/Code/Review/itkJPEG2000ImageIO.cxx
index 53027b74d3..7e1ba99e4d 100644
--- a/Code/Review/itkJPEG2000ImageIO.cxx
+++ b/Code/Review/itkJPEG2000ImageIO.cxx
@@ -766,6 +766,30 @@ ::Write(const void *buffer)
   w = this->m_Dimensions[0];
   h = this->m_Dimensions[1];
 
+
+  // Compute the proper number of resolutions to use.
+  // This is mostly done for images smaller than 64 pixels
+  // along any dimension.
+  unsigned int numberOfResolutions = 0;
+
+  int tw = w >> 1;
+  int th = h >> 1;
+
+  while( tw && th )
+    {
+    numberOfResolutions++;
+    tw >>= 1;
+    th >>= 1;
+    }
+
+  // Clamp the number of resolutions to 6.
+  if( numberOfResolutions > 6 )
+    {
+    numberOfResolutions = 6;
+    }
+
+  parameters.numresolution = numberOfResolutions;
+
   OPJ_COLOR_SPACE      color_space = CLRSPC_GRAY;
   opj_image_cmptparm_t cmptparm[3];