--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.3/spandsp-0.0.3/itutests/fax/generate_dithered_tif.c	Fri Jun 25 16:00:21 2010 +0200
@@ -0,0 +1,170 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * generate_dithered_tif.c - Create a fine checkerboard TIFF file for test purposes.
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2006 Steve Underwood
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id: generate_dithered_tif.c,v 1.3 2006/11/20 00:00:27 steveu Exp $
+ */
+
+/*! \file */
+
+/*
+    This program generates an A4 sized FAX image of a fine checkerboard. This doesn't
+    compress well, so it results in a rather large file for a single page. This is
+    good for testing the handling of extreme pages.
+    
+    Note that due to a bug in FAX image handling, versions of libtiff up to 3.8.2 fail
+    to handle this complex image properly, if 2-D compression is used. The bug should
+    be fixed in CVS at the time of writing, and so should be fixed in released versions
+    after 3.8.2. This code uses 1-D compression to avoid the issue.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#define _GNU_SOURCE
+
+#include <stdio.h>
+#include <inttypes.h>
+#include <limits.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <time.h>
+#include <memory.h>
+#include <string.h>
+#if defined(HAVE_TGMATH_H)
+#include <tgmath.h>
+#endif
+#if defined(HAVE_MATH_H)
+#include <math.h>
+#endif
+#include <tiffio.h>
+
+#define T4_X_RESOLUTION_R4          4019
+#define T4_X_RESOLUTION_R8          8037
+#define T4_X_RESOLUTION_R16         16074
+
+#define T4_Y_RESOLUTION_STANDARD    3850
+#define T4_Y_RESOLUTION_FINE        7700
+#define T4_Y_RESOLUTION_SUPERFINE   15400
+
+int main(int argc, char *argv[])
+{
+    int image_width;
+    int row;
+    int resunit;
+    int output_compression;
+    int output_t4_options;
+    uint8_t image_buffer[1024];
+    TIFF *tiff_file;
+    struct tm *tm;
+    time_t now;
+    char buf[133];
+    float x_resolution;
+    float y_resolution;
+    int x_res;
+    int y_res;
+    int image_length;
+
+    if ((tiff_file = TIFFOpen("dithered.tif", "w")) == NULL)
+        exit(2);
+
+    output_compression = COMPRESSION_CCITT_T4;
+    /* Use 1-D compression until a fixed libtiff is the norm. */
+    //output_t4_options = GROUP3OPT_FILLBITS | GROUP3OPT_2DENCODING;
+    output_t4_options = GROUP3OPT_FILLBITS;
+
+    x_res = T4_X_RESOLUTION_R8;
+    y_res = T4_Y_RESOLUTION_FINE;
+    image_width = 1728;
+    image_length = 2200;
+
+    /* Prepare the directory entry fully before writing the image, or libtiff complains */
+    TIFFSetField(tiff_file, TIFFTAG_COMPRESSION, output_compression);
+    if (output_compression == COMPRESSION_CCITT_T4)
+    {
+        TIFFSetField(tiff_file, TIFFTAG_T4OPTIONS, output_t4_options);
+        TIFFSetField(tiff_file, TIFFTAG_FAXMODE, FAXMODE_CLASSF);
+    }
+    TIFFSetField(tiff_file, TIFFTAG_IMAGEWIDTH, image_width);
+    TIFFSetField(tiff_file, TIFFTAG_BITSPERSAMPLE, 1);
+    TIFFSetField(tiff_file, TIFFTAG_ORIENTATION, ORIENTATION_TOPLEFT);
+    TIFFSetField(tiff_file, TIFFTAG_SAMPLESPERPIXEL, 1);
+    TIFFSetField(tiff_file, TIFFTAG_ROWSPERSTRIP, -1L);
+    TIFFSetField(tiff_file, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG);
+    TIFFSetField(tiff_file, TIFFTAG_PHOTOMETRIC, PHOTOMETRIC_MINISWHITE);
+    TIFFSetField(tiff_file, TIFFTAG_FILLORDER, FILLORDER_LSB2MSB);
+
+    x_resolution = x_res/100.0f;
+    y_resolution = y_res/100.0f;
+    TIFFSetField(tiff_file, TIFFTAG_XRESOLUTION, floorf(x_resolution*2.54f + 0.5f));
+    TIFFSetField(tiff_file, TIFFTAG_YRESOLUTION, floorf(y_resolution*2.54f + 0.5f));
+    resunit = RESUNIT_INCH;
+    TIFFSetField(tiff_file, TIFFTAG_RESOLUTIONUNIT, resunit);
+
+    TIFFSetField(tiff_file, TIFFTAG_SOFTWARE, "spandsp");
+    if (gethostname(buf, sizeof(buf)) == 0)
+        TIFFSetField(tiff_file, TIFFTAG_HOSTCOMPUTER, buf);
+
+    TIFFSetField(tiff_file, TIFFTAG_IMAGEDESCRIPTION, "Checkerboard or dithered ones");
+    TIFFSetField(tiff_file, TIFFTAG_MAKE, "soft-switch.org");
+    TIFFSetField(tiff_file, TIFFTAG_MODEL, "test data");
+
+    time(&now);
+    tm = localtime(&now);
+    sprintf(buf,
+    	    "%4d/%02d/%02d %02d:%02d:%02d",
+            tm->tm_year + 1900,
+            tm->tm_mon + 1,
+            tm->tm_mday,
+            tm->tm_hour,
+            tm->tm_min,
+            tm->tm_sec);
+    TIFFSetField(tiff_file, TIFFTAG_DATETIME, buf);
+
+    TIFFSetField(tiff_file, TIFFTAG_IMAGELENGTH, image_length);
+    TIFFSetField(tiff_file, TIFFTAG_PAGENUMBER, 0, 1);
+    TIFFSetField(tiff_file, TIFFTAG_CLEANFAXDATA, CLEANFAXDATA_CLEAN);
+    TIFFSetField(tiff_file, TIFFTAG_IMAGEWIDTH, image_width);
+
+    /* Write the image first.... */
+    for (row = 0;  row < image_length;  row++)
+    {
+        if ((row & 1) == 0)
+            memset(image_buffer, 0xAA, image_width/8 + 1);
+        else
+            memset(image_buffer, 0x55, image_width/8 + 1);
+        if (TIFFWriteScanline(tiff_file, image_buffer, row, 0) < 0)
+        {
+            printf("Write error at row %d.\n", row);
+            exit(2);
+        }
+    }
+    /* ....then the directory entry, and libtiff is happy. */
+    TIFFWriteDirectory(tiff_file);
+    TIFFClose(tiff_file);
+    return 0;
+}
+/*- End of function --------------------------------------------------------*/
+/*- End of file ------------------------------------------------------------*/