Rearrange source files.

1 files changed, 202 insertions, 0 deletions

diff --git a/source/fitz/halftone.c b/source/fitz/halftone.c
new file mode 100644
index 00000000..15aebead
--- /dev/null
+++ b/source/fitz/halftone.c
@@ -0,0 +1,202 @@
+#include "mupdf/fitz.h"
+
+fz_halftone *
+fz_new_halftone(fz_context *ctx, int comps)
+{
+	fz_halftone *ht;
+	int i;
+
+	ht = fz_malloc(ctx, sizeof(fz_halftone) + (comps-1)*sizeof(fz_pixmap *));
+	ht->refs = 1;
+	ht->n = comps;
+	for (i = 0; i < comps; i++)
+		ht->comp[i] = NULL;
+
+	return ht;
+}
+
+fz_halftone *
+fz_keep_halftone(fz_context *ctx, fz_halftone *ht)
+{
+	if (ht)
+		ht->refs++;
+	return ht;
+}
+
+void
+fz_drop_halftone(fz_context *ctx, fz_halftone *ht)
+{
+	int i;
+
+	if (!ht || --ht->refs != 0)
+		return;
+	for (i = 0; i < ht->n; i++)
+		fz_drop_pixmap(ctx, ht->comp[i]);
+	fz_free(ctx, ht);
+}
+
+/* Default mono halftone, lifted from Ghostscript. */
+/* The 0x00 entry has been changed to 0x01 to avoid problems with white
+ * pixels appearing in the output; as we use < 0 should not appear in the
+ * array. I think that gs scales this slighly and hence never actually uses
+ * the raw values here. */
+static unsigned char mono_ht[] =
+{
+	0x0E, 0x8E, 0x2E, 0xAE, 0x06, 0x86, 0x26, 0xA6, 0x0C, 0x8C, 0x2C, 0xAC, 0x04, 0x84, 0x24, 0xA4,
+	0xCE, 0x4E, 0xEE, 0x6E, 0xC6, 0x46, 0xE6, 0x66, 0xCC, 0x4C, 0xEC, 0x6C, 0xC4, 0x44, 0xE4, 0x64,
+	0x3E, 0xBE, 0x1E, 0x9E, 0x36, 0xB6, 0x16, 0x96, 0x3C, 0xBC, 0x1C, 0x9C, 0x34, 0xB4, 0x14, 0x94,
+	0xFE, 0x7E, 0xDE, 0x5E, 0xF6, 0x76, 0xD6, 0x56, 0xFC, 0x7C, 0xDC, 0x5C, 0xF4, 0x74, 0xD4, 0x54,
+	0x01, 0x81, 0x21, 0xA1, 0x09, 0x89, 0x29, 0xA9, 0x03, 0x83, 0x23, 0xA3, 0x0B, 0x8B, 0x2B, 0xAB,
+	0xC1, 0x41, 0xE1, 0x61, 0xC9, 0x49, 0xE9, 0x69, 0xC3, 0x43, 0xE3, 0x63, 0xCB, 0x4B, 0xEB, 0x6B,
+	0x31, 0xB1, 0x11, 0x91, 0x39, 0xB9, 0x19, 0x99, 0x33, 0xB3, 0x13, 0x93, 0x3B, 0xBB, 0x1B, 0x9B,
+	0xF1, 0x71, 0xD1, 0x51, 0xF9, 0x79, 0xD9, 0x59, 0xF3, 0x73, 0xD3, 0x53, 0xFB, 0x7B, 0xDB, 0x5B,
+	0x0D, 0x8D, 0x2D, 0xAD, 0x05, 0x85, 0x25, 0xA5, 0x0F, 0x8F, 0x2F, 0xAF, 0x07, 0x87, 0x27, 0xA7,
+	0xCD, 0x4D, 0xED, 0x6D, 0xC5, 0x45, 0xE5, 0x65, 0xCF, 0x4F, 0xEF, 0x6F, 0xC7, 0x47, 0xE7, 0x67,
+	0x3D, 0xBD, 0x1D, 0x9D, 0x35, 0xB5, 0x15, 0x95, 0x3F, 0xBF, 0x1F, 0x9F, 0x37, 0xB7, 0x17, 0x97,
+	0xFD, 0x7D, 0xDD, 0x5D, 0xF5, 0x75, 0xD5, 0x55, 0xFF, 0x7F, 0xDF, 0x5F, 0xF7, 0x77, 0xD7, 0x57,
+	0x02, 0x82, 0x22, 0xA2, 0x0A, 0x8A, 0x2A, 0xAA, 0x01 /*0x00*/, 0x80, 0x20, 0xA0, 0x08, 0x88, 0x28, 0xA8,
+	0xC2, 0x42, 0xE2, 0x62, 0xCA, 0x4A, 0xEA, 0x6A, 0xC0, 0x40, 0xE0, 0x60, 0xC8, 0x48, 0xE8, 0x68,
+	0x32, 0xB2, 0x12, 0x92, 0x3A, 0xBA, 0x1A, 0x9A, 0x30, 0xB0, 0x10, 0x90, 0x38, 0xB8, 0x18, 0x98,
+	0xF2, 0x72, 0xD2, 0x52, 0xFA, 0x7A, 0xDA, 0x5A, 0xF0, 0x70, 0xD0, 0x50, 0xF8, 0x78, 0xD8, 0x58
+};
+
+fz_halftone *fz_default_halftone(fz_context *ctx, int num_comps)
+{
+	fz_halftone *ht = fz_new_halftone(ctx, num_comps);
+	assert(num_comps == 1); /* Only support 1 component for now */
+	ht->comp[0] = fz_new_pixmap_with_data(ctx, NULL, 16, 16, mono_ht);
+	return ht;
+}
+
+/* Finally, code to actually perform halftoning. */
+static void make_ht_line(unsigned char *buf, fz_halftone *ht, int x, int y, int w)
+{
+	/* FIXME: There is a potential optimisation here; in the case where
+	 * the LCM of the halftone tile widths is smaller than w, we could
+	 * form just one 'LCM' run, then copy it repeatedly.
+	 */
+	int k, n;
+	n = ht->n;
+	for (k = 0; k < n; k++)
+	{
+		fz_pixmap *tile = ht->comp[k];
+		unsigned char *b = buf++;
+		unsigned char *t;
+		unsigned char *tbase;
+		int px = x + tile->x;
+		int py = y + tile->y;
+		int tw = tile->w;
+		int th = tile->h;
+		int w2 = w;
+		int len;
+		px = px % tw;
+		if (px < 0)
+			px += tw;
+		py = py % th;
+		if (py < 0)
+			py += th;
+
+		assert(tile->n == 1);
+
+		/* Left hand section; from x to tile width */
+		tbase = tile->samples + (unsigned int)(py * tw);
+		t = tbase + px;
+		len = tw - px;
+		if (len > w2)
+			len = w2;
+		w2 -= len;
+		while (len--)
+		{
+			*b = *t++;
+			b += n;
+		}
+
+		/* Centre section - complete copies */
+		w2 -= tw;
+		while (w2 >= 0)
+		{
+			len = tw;
+			t = tbase;
+			while (len--)
+			{
+				*b = *t++;
+				b += n;
+			}
+			w2 -= tw;
+		}
+		w2 += tw;
+
+		/* Right hand section - stragglers */
+		t = tbase;
+		while (w2--)
+		{
+			*b = *t++;
+			b += n;
+		}
+	}
+}
+
+/* Inner mono thresholding code */
+static void do_threshold_1(unsigned char *ht_line, unsigned char *pixmap, unsigned char *out, int w)
+{
+	int bit = 0x80;
+	int h = 0;
+
+	do
+	{
+		if (*pixmap < *ht_line++)
+			h |= bit;
+		pixmap += 2; /* Skip the alpha */
+		bit >>= 1;
+		if (bit == 0)
+		{
+			*out++ = h;
+			h = 0;
+			bit = 0x80;
+		}
+
+	}
+	while (--w);
+	if (bit != 0x80)
+		*out++ = h;
+}
+
+fz_bitmap *fz_halftone_pixmap(fz_context *ctx, fz_pixmap *pix, fz_halftone *ht)
+{
+	fz_bitmap *out;
+	unsigned char *ht_line, *o, *p;
+	int w, h, x, y, n, pstride, ostride;
+	fz_halftone *ht_orig = ht;
+
+	if (!pix)
+		return NULL;
+
+	assert(pix->n == 2); /* Mono + Alpha */
+
+	n = pix->n-1; /* Remove alpha */
+	if (ht == NULL)
+	{
+		ht = fz_default_halftone(ctx, n);
+	}
+	ht_line = fz_malloc(ctx, pix->w * n);
+	out = fz_new_bitmap(ctx, pix->w, pix->h, n, pix->xres, pix->yres);
+	o = out->samples;
+	p = pix->samples;
+
+	h = pix->h;
+	x = pix->x;
+	y = pix->y;
+	w = pix->w;
+	ostride = out->stride;
+	pstride = pix->w * pix->n;
+	while (h--)
+	{
+		make_ht_line(ht_line, ht, x, y++, w);
+		do_threshold_1(ht_line, p, o, w);
+		o += ostride;
+		p += pstride;
+	}
+	if (!ht_orig)
+		fz_drop_halftone(ctx, ht);
+	return out;
+}