diff --git a/src/image.c b/src/image.c
--- /dev/null
+++ b/src/image.c
@@ -0,0 +1,158 @@
+/***************************************************************************
+ * This file is a part of CADS/UVS fits2jpeg conversion software *
+ * Copyright (C) 2012 by CADS/UV Software Team, *
+ * Indian Institute of Astrophysics *
+ * Bangalore 560034 *
+ * cads_AT_iiap.res.in *
+ * *
+ * This program is free software; you can redistribute it and/or modify *
+ * it under the terms of the GNU General Public License as published by *
+ * the Free Software Foundation; either version 2 of the License, or *
+ * (at your option) any later version. *
+ * *
+ * This program is distributed in the hope that it will be useful, *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
+ * GNU General Public License for more details. *
+ * *
+ * You should have received a copy of the GNU General Public License *
+ * along with this program; if not, write to the *
+ * Free Software Foundation, Inc., *
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
+ ***************************************************************************/
+
+/*Header Definitions*/
+#include "fits2jpeg.h"
+
+void scale_image(int scale, int npixels,
+ float *data, JSAMPLE *image_buffer)
+{
+ unsigned int i = 0;
+ int JMAXVAL = 255;
+ float datamax = 0.0, datamin = 0.0, tmp = 0.0;
+ float hist[256] = {0.0}, cumhist[256] = {0.0};
+ float scl_data = 0.0;
+
+
+ /* first find min & max in data */
+ datamax = -1.0 * FLT_MAX;
+ datamin = FLT_MAX;
+ for (i = 0; i < npixels; ++i)
+ {
+ if (data[i] > datamax) datamax = data[i];
+ if (data[i] < datamin) datamin = data[i];
+ } /*endfor*/
+
+ /* Convert data into bytscaled values for jpeg file */
+ /* the dynamic range is reduced to 255 for jpeg */
+ scl_data = (datamax - datamin)/(float)JMAXVAL;
+ for (i = 0; i < npixels; ++i)
+ data[i] = (data[i] - datamin)/scl_data;
+
+ /* All data is now squeezed into the range 0 - 255 */
+ /* NOTE: At this point onwards min & max is 0 and 255 respectively */
+ datamax = (float)JMAXVAL;
+ datamin = 0.0;
+
+ /* initialize image histogram. ensure all are zeroes in hist[] */
+ /*-------------------------------------------------------------------*/
+ for (i = 0; i <= JMAXVAL; ++i) hist[i] = 0;
+
+ /* construct the image histogram */
+ tmp = 1.0/(float)npixels;
+ for (i = 0; i <= npixels; ++i)
+ hist[(int)floor(data[i])] += tmp;
+
+ /* And the cumulative histogram */
+ cumhist[0] = hist[0];
+ for (i = 1; i <= JMAXVAL; ++i)
+ cumhist[i] += cumhist[i - 1] + hist[i];
+
+ /* Linear scale (min-max) : This is the default scaling
+ * if we dont generate image_buffer here, histo-eq will fail */
+ for (i = 0; i < npixels; ++i)
+ image_buffer[i] = (int)(data[i]);
+
+ /*-------------------------------------------------------------------*/
+
+
+ switch (scale)
+ {
+ case 1 : /* Square root */
+ printinfo("Using square-root scale");
+ scl_data = sqrt((float)JMAXVAL)/(float)JMAXVAL;
+ for (i = 0; i < npixels; ++i)
+ image_buffer[i] = (int)(sqrt(data[i])/scl_data);
+ break;
+
+ case 2 : /* Square */
+ printinfo("Using quadratic scale");
+ scl_data = pow((float)JMAXVAL,2)/(float)JMAXVAL;
+ for (i = 0; i < npixels; ++i)
+ image_buffer[i] = (int)abs((pow(data[i],2) - 1.0)/scl_data);
+ break;
+
+ case 3 : /* Cubic */
+ printinfo("Using cubic scale");
+ scl_data = pow((float)JMAXVAL,3)/(float)JMAXVAL;
+ for (i = 0; i < npixels; ++i)
+ image_buffer[i] = (int)abs((pow(data[i],3) - 1.0)/scl_data);
+ break;
+
+ case 4 : /* log */
+ printinfo("Using log scale");
+ scl_data = log(1.0 + (float)JMAXVAL)/(float)JMAXVAL;
+ for (i = 0; i < npixels; ++i)
+ image_buffer[i] = (int)((log(abs(data[i]) + 1.0))/scl_data);
+ break;
+
+ case 5 :
+ /* contrast stretch */
+ printinfo("Performing histogram stretch (normalization)");
+
+ /* We need to go through the cumulative histogram to pick the
+ * appropriate values for datamin and datamax */
+ i = 0;
+ while (i < JMAXVAL)
+ {
+ if (cumhist[i] >= 0.01)
+ {
+ datamin = (float) i;
+ break;
+ }
+ i++;
+ }
+ i = JMAXVAL;
+ while (i > 0)
+ {
+ if (cumhist[i] <= 0.99)
+ {
+ datamax = (float) i;
+ break;
+ }
+ i--;
+ }
+ scl_data = (datamax - datamin)/(float)JMAXVAL;
+ for (i = 0; i < npixels; ++i)
+ {
+ if (image_buffer[i] >= datamax)
+ image_buffer[i] = JMAXVAL;
+ else if (image_buffer[i] <= datamin)
+ image_buffer[i] = 0;
+ else
+ image_buffer[i] = (int) abs((image_buffer[i] - datamin)/scl_data);
+ }
+ break;
+
+ case 6 :
+ /* histogram equalization */
+ printinfo("Performing Histogram Equalization");
+ for (i = 0; i < npixels; ++i)
+ image_buffer[i] = cumhist[image_buffer[i]] * 255;
+ break;
+ default :
+ printinfo("Using linear scale");
+ break;
+ }
+
+}