1 files changed, 334 insertions, 0 deletions
diff --git a/tiff/tools/tiffdither.c b/tiff/tools/tiffdither.c
new file mode 100755
index 0000000..4308946
--- /dev/null
+++ b/tiff/tools/tiffdither.c
@@ -0,0 +1,334 @@
+/* $Id: tiffdither.c,v 1.14 2013-05-02 14:44:29 tgl Exp $ */
+
+/*
+ * Copyright (c) 1988-1997 Sam Leffler
+ * Copyright (c) 1991-1997 Silicon Graphics, Inc.
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and 
+ * its documentation for any purpose is hereby granted without fee, provided
+ * that (i) the above copyright notices and this permission notice appear in
+ * all copies of the software and related documentation, and (ii) the names of
+ * Sam Leffler and Silicon Graphics may not be used in any advertising or
+ * publicity relating to the software without the specific, prior written
+ * permission of Sam Leffler and Silicon Graphics.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, 
+ * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY 
+ * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.  
+ * 
+ * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
+ * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
+ * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+ * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF 
+ * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 
+ * OF THIS SOFTWARE.
+ */
+
+#include "tif_config.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
+#ifdef NEED_LIBPORT
+# include "libport.h"
+#endif
+
+#include "tiffio.h"
+
+#define	streq(a,b)	(strcmp(a,b) == 0)
+#define	strneq(a,b,n)	(strncmp(a,b,n) == 0)
+
+#define	CopyField(tag, v) \
+	if (TIFFGetField(in, tag, &v)) TIFFSetField(out, tag, v)
+
+uint32	imagewidth;
+uint32	imagelength;
+int	threshold = 128;
+
+static	void usage(void);
+
+/* 
+ * Floyd-Steinberg error propragation with threshold.
+ * This code is stolen from tiffmedian.
+ */
+static void
+fsdither(TIFF* in, TIFF* out)
+{
+	unsigned char *outline, *inputline, *inptr;
+	short *thisline, *nextline, *tmpptr;
+	register unsigned char	*outptr;
+	register short *thisptr, *nextptr;
+	register uint32 i, j;
+	uint32 imax, jmax;
+	int lastline, lastpixel;
+	int bit;
+	tsize_t outlinesize;
+
+	imax = imagelength - 1;
+	jmax = imagewidth - 1;
+	inputline = (unsigned char *)_TIFFmalloc(TIFFScanlineSize(in));
+	thisline = (short *)_TIFFmalloc(imagewidth * sizeof (short));
+	nextline = (short *)_TIFFmalloc(imagewidth * sizeof (short));
+	outlinesize = TIFFScanlineSize(out);
+	outline = (unsigned char *) _TIFFmalloc(outlinesize);
+
+	/*
+	 * Get first line
+	 */
+	if (TIFFReadScanline(in, inputline, 0, 0) <= 0)
+            goto skip_on_error;
+
+	inptr = inputline;
+	nextptr = nextline;
+	for (j = 0; j < imagewidth; ++j)
+		*nextptr++ = *inptr++;
+	for (i = 1; i < imagelength; ++i) {
+		tmpptr = thisline;
+		thisline = nextline;
+		nextline = tmpptr;
+		lastline = (i == imax);
+		if (TIFFReadScanline(in, inputline, i, 0) <= 0)
+			break;
+		inptr = inputline;
+		nextptr = nextline;
+		for (j = 0; j < imagewidth; ++j)
+			*nextptr++ = *inptr++;
+		thisptr = thisline;
+		nextptr = nextline;
+		_TIFFmemset(outptr = outline, 0, outlinesize);
+		bit = 0x80;
+		for (j = 0; j < imagewidth; ++j) {
+			register int v;
+
+			lastpixel = (j == jmax);
+			v = *thisptr++;
+			if (v < 0)
+				v = 0;
+			else if (v > 255)
+				v = 255;
+			if (v > threshold) {
+				*outptr |= bit;
+				v -= 255;
+			}
+			bit >>= 1;
+			if (bit == 0) {
+				outptr++;
+				bit = 0x80;
+			}
+			if (!lastpixel)
+				thisptr[0] += v * 7 / 16;
+			if (!lastline) {
+				if (j != 0)
+					nextptr[-1] += v * 3 / 16;
+				*nextptr++ += v * 5 / 16;
+				if (!lastpixel)
+					nextptr[0] += v / 16;
+			}
+		}
+		if (TIFFWriteScanline(out, outline, i-1, 0) < 0)
+			break;
+	}
+  skip_on_error:
+	_TIFFfree(inputline);
+	_TIFFfree(thisline);
+	_TIFFfree(nextline);
+	_TIFFfree(outline);
+}
+
+static	uint16 compression = COMPRESSION_PACKBITS;
+static	uint16 predictor = 0;
+static	uint32 group3options = 0;
+
+static void
+processG3Options(char* cp)
+{
+	if ((cp = strchr(cp, ':'))) {
+		do {
+			cp++;
+			if (strneq(cp, "1d", 2))
+				group3options &= ~GROUP3OPT_2DENCODING;
+			else if (strneq(cp, "2d", 2))
+				group3options |= GROUP3OPT_2DENCODING;
+			else if (strneq(cp, "fill", 4))
+				group3options |= GROUP3OPT_FILLBITS;
+			else
+				usage();
+		} while ((cp = strchr(cp, ':')));
+	}
+}
+
+static int
+processCompressOptions(char* opt)
+{
+	if (streq(opt, "none"))
+		compression = COMPRESSION_NONE;
+	else if (streq(opt, "packbits"))
+		compression = COMPRESSION_PACKBITS;
+	else if (strneq(opt, "g3", 2)) {
+		processG3Options(opt);
+		compression = COMPRESSION_CCITTFAX3;
+	} else if (streq(opt, "g4"))
+		compression = COMPRESSION_CCITTFAX4;
+	else if (strneq(opt, "lzw", 3)) {
+		char* cp = strchr(opt, ':');
+		if (cp)
+			predictor = atoi(cp+1);
+		compression = COMPRESSION_LZW;
+	} else if (strneq(opt, "zip", 3)) {
+		char* cp = strchr(opt, ':');
+		if (cp)
+			predictor = atoi(cp+1);
+		compression = COMPRESSION_DEFLATE;
+	} else
+		return (0);
+	return (1);
+}
+
+int
+main(int argc, char* argv[])
+{
+	TIFF *in, *out;
+	uint16 samplesperpixel, bitspersample = 1, shortv;
+	float floatv;
+	char thing[1024];
+	uint32 rowsperstrip = (uint32) -1;
+	uint16 fillorder = 0;
+	int c;
+	extern int optind;
+	extern char *optarg;
+
+	while ((c = getopt(argc, argv, "c:f:r:t:")) != -1)
+		switch (c) {
+		case 'c':		/* compression scheme */
+			if (!processCompressOptions(optarg))
+				usage();
+			break;
+		case 'f':		/* fill order */
+			if (streq(optarg, "lsb2msb"))
+				fillorder = FILLORDER_LSB2MSB;
+			else if (streq(optarg, "msb2lsb"))
+				fillorder = FILLORDER_MSB2LSB;
+			else
+				usage();
+			break;
+		case 'r':		/* rows/strip */
+			rowsperstrip = atoi(optarg);
+			break;
+		case 't':
+			threshold = atoi(optarg);
+			if (threshold < 0)
+				threshold = 0;
+			else if (threshold > 255)
+				threshold = 255;
+			break;
+		case '?':
+			usage();
+			/*NOTREACHED*/
+		}
+	if (argc - optind < 2)
+		usage();
+	in = TIFFOpen(argv[optind], "r");
+	if (in == NULL)
+		return (-1);
+	TIFFGetField(in, TIFFTAG_SAMPLESPERPIXEL, &samplesperpixel);
+	if (samplesperpixel != 1) {
+		fprintf(stderr, "%s: Not a b&w image.\n", argv[0]);
+		return (-1);
+	}
+	TIFFGetField(in, TIFFTAG_BITSPERSAMPLE, &bitspersample);
+	if (bitspersample != 8) {
+		fprintf(stderr,
+		    " %s: Sorry, only handle 8-bit samples.\n", argv[0]);
+		return (-1);
+	}
+	out = TIFFOpen(argv[optind+1], "w");
+	if (out == NULL)
+		return (-1);
+	CopyField(TIFFTAG_IMAGEWIDTH, imagewidth);
+	TIFFGetField(in, TIFFTAG_IMAGELENGTH, &imagelength);
+	TIFFSetField(out, TIFFTAG_IMAGELENGTH, imagelength-1);
+	TIFFSetField(out, TIFFTAG_BITSPERSAMPLE, 1);
+	TIFFSetField(out, TIFFTAG_SAMPLESPERPIXEL, 1);
+	TIFFSetField(out, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG);
+	TIFFSetField(out, TIFFTAG_COMPRESSION, compression);
+	if (fillorder)
+		TIFFSetField(out, TIFFTAG_FILLORDER, fillorder);
+	else
+		CopyField(TIFFTAG_FILLORDER, shortv);
+	snprintf(thing, sizeof(thing), "Dithered B&W version of %s", argv[optind]);
+	TIFFSetField(out, TIFFTAG_IMAGEDESCRIPTION, thing);
+	CopyField(TIFFTAG_PHOTOMETRIC, shortv);
+	CopyField(TIFFTAG_ORIENTATION, shortv);
+	CopyField(TIFFTAG_XRESOLUTION, floatv);
+	CopyField(TIFFTAG_YRESOLUTION, floatv);
+	CopyField(TIFFTAG_RESOLUTIONUNIT, shortv);
+        rowsperstrip = TIFFDefaultStripSize(out, rowsperstrip);
+	TIFFSetField(out, TIFFTAG_ROWSPERSTRIP, rowsperstrip);
+	switch (compression) {
+	case COMPRESSION_CCITTFAX3:
+		TIFFSetField(out, TIFFTAG_GROUP3OPTIONS, group3options);
+		break;
+	case COMPRESSION_LZW:
+	case COMPRESSION_DEFLATE:
+		if (predictor)
+			TIFFSetField(out, TIFFTAG_PREDICTOR, predictor);
+		break;
+	}
+	fsdither(in, out);
+	TIFFClose(in);
+	TIFFClose(out);
+	return (0);
+}
+
+char* stuff[] = {
+"usage: tiffdither [options] input.tif output.tif",
+"where options are:",
+" -r #		make each strip have no more than # rows",
+" -t #		set the threshold value for dithering (default 128)",
+" -f lsb2msb	force lsb-to-msb FillOrder for output",
+" -f msb2lsb	force msb-to-lsb FillOrder for output",
+" -c lzw[:opts]	compress output with Lempel-Ziv & Welch encoding",
+" -c zip[:opts]	compress output with deflate encoding",
+" -c packbits	compress output with packbits encoding",
+" -c g3[:opts]	compress output with CCITT Group 3 encoding",
+" -c g4		compress output with CCITT Group 4 encoding",
+" -c none	use no compression algorithm on output",
+"",
+"Group 3 options:",
+" 1d		use default CCITT Group 3 1D-encoding",
+" 2d		use optional CCITT Group 3 2D-encoding",
+" fill		byte-align EOL codes",
+"For example, -c g3:2d:fill to get G3-2D-encoded data with byte-aligned EOLs",
+"",
+"LZW and deflate options:",
+" #		set predictor value",
+"For example, -c lzw:2 to get LZW-encoded data with horizontal differencing",
+NULL
+};
+
+static void
+usage(void)
+{
+	char buf[BUFSIZ];
+	int i;
+
+	setbuf(stderr, buf);
+        fprintf(stderr, "%s\n\n", TIFFGetVersion());
+	for (i = 0; stuff[i] != NULL; i++)
+		fprintf(stderr, "%s\n", stuff[i]);
+	exit(-1);
+}
+
+/* vim: set ts=8 sts=8 sw=8 noet: */
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 8
+ * fill-column: 78
+ * End:
+ */