Initial commit.

1 files changed, 205 insertions, 0 deletions

diff --git a/compress.c b/compress.c
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index 0000000..3c97806
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+++ b/compress.c
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+/*
+ *  Compface - 48x48x1 image compression and decompression
+ *
+ *  Copyright (c) James Ashton - Sydney University - June 1990.
+ *
+ *  Written 11th November 1989.
+ *
+ *  Permission is given to distribute these sources, as long as the
+ *  copyright messages are not removed, and no monies are exchanged. 
+ *
+ *  No responsibility is taken for any errors on inaccuracies inherent
+ *  either to the comments or the code of this program, but if reported
+ *  to me, then an attempt will be made to fix them.
+ */
+
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "compface.h"
+
+int
+Same(f, wid, hei)
+register char *f;
+register int wid, hei;
+{
+	register char val, *row;
+	register int x;
+
+	val = *f;
+	while (hei--)
+	{
+		row = f;
+		x = wid;
+		while (x--)
+			if (*(row++) != val)
+				return(0);
+		f += WIDTH;
+	}
+	return 1;
+}
+
+int
+AllBlack(f, wid, hei)
+char *f;
+int wid, hei;
+{
+	if (wid > 3)
+	{
+		wid /= 2;
+		hei /= 2;
+		return (AllBlack(f, wid, hei) && AllBlack(f + wid, wid, hei) &&
+		  AllBlack(f + WIDTH * hei, wid, hei) &&
+		  AllBlack(f + WIDTH * hei + wid, wid, hei));
+	}
+	else
+		return (*f || *(f + 1) || *(f + WIDTH) || *(f + WIDTH + 1));
+}
+
+int
+AllWhite(f, wid, hei)
+char *f;
+int wid, hei;
+{
+	return ((*f == 0) && Same(f, wid, hei));
+}
+
+void
+PopGreys(f, wid, hei)
+char *f;
+int wid, hei;
+{
+	if (wid > 3)
+	{
+		wid /= 2;
+		hei /= 2;
+		PopGreys(f, wid, hei);
+		PopGreys(f + wid, wid, hei);
+		PopGreys(f + WIDTH * hei, wid, hei);
+		PopGreys(f + WIDTH * hei + wid, wid, hei);
+	}
+	else
+	{
+		wid = BigPop(freqs);
+		if (wid & 1)
+			*f = 1;
+		if (wid & 2)
+			*(f + 1) = 1;
+		if (wid & 4)
+			*(f + WIDTH) = 1;
+		if (wid & 8)
+			*(f + WIDTH + 1) = 1;
+	}
+}
+
+void
+PushGreys(f, wid, hei)
+char *f;
+int wid, hei;
+{
+	if (wid > 3)
+	{
+		wid /= 2;
+		hei /= 2;
+		PushGreys(f, wid, hei);
+		PushGreys(f + wid, wid, hei);
+		PushGreys(f + WIDTH * hei, wid, hei);
+		PushGreys(f + WIDTH * hei + wid, wid, hei);
+	}
+	else
+		RevPush(freqs + *f + 2 * *(f + 1) + 4 * *(f + WIDTH) +
+		  8 * *(f + WIDTH + 1));
+}
+
+void
+UnCompress(f, wid, hei, lev)
+register char *f;
+register int wid, hei, lev;
+{
+	switch (BigPop(&levels[lev][0]))
+	{
+		case WHITE :
+			return;
+		case BLACK :
+			PopGreys(f, wid, hei);
+			return;
+		default :
+			wid /= 2;
+			hei /= 2;
+			lev++;
+			UnCompress(f, wid, hei, lev);
+			UnCompress(f + wid, wid, hei, lev);
+			UnCompress(f + hei * WIDTH, wid, hei, lev);
+			UnCompress(f + wid + hei * WIDTH, wid, hei, lev);
+			return;
+	}
+}
+
+void
+Compress(f, wid, hei, lev)
+register char *f;
+register int wid, hei, lev;
+{
+	if (AllWhite(f, wid, hei))
+	{
+		RevPush(&levels[lev][WHITE]);
+		return;
+	}
+	if (AllBlack(f, wid, hei))
+	{
+		RevPush(&levels[lev][BLACK]);
+		PushGreys(f, wid, hei);
+		return;
+	}
+	RevPush(&levels[lev][GREY]);
+	wid /= 2;
+	hei /= 2;
+	lev++;
+	Compress(f, wid, hei, lev);
+	Compress(f + wid, wid, hei, lev);
+	Compress(f + hei * WIDTH, wid, hei, lev);
+	Compress(f + wid + hei * WIDTH, wid, hei, lev);
+}
+
+void
+UnCompAll(fbuf)
+char *fbuf;
+{
+	register char *p;
+
+	BigClear();
+	BigRead(fbuf);
+	p = F;
+	while (p < F + PIXELS)
+		*(p++) = 0;
+	UnCompress(F, 16, 16, 0);
+	UnCompress(F + 16, 16, 16, 0);
+	UnCompress(F + 32, 16, 16, 0);
+	UnCompress(F + WIDTH * 16, 16, 16, 0);
+	UnCompress(F + WIDTH * 16 + 16, 16, 16, 0);
+	UnCompress(F + WIDTH * 16 + 32, 16, 16, 0);
+	UnCompress(F + WIDTH * 32, 16, 16, 0);
+	UnCompress(F + WIDTH * 32 + 16, 16, 16, 0);
+	UnCompress(F + WIDTH * 32 + 32, 16, 16, 0);
+}
+
+void
+CompAll(fbuf)
+char *fbuf;
+{
+	Compress(F, 16, 16, 0);
+	Compress(F + 16, 16, 16, 0);
+	Compress(F + 32, 16, 16, 0);
+	Compress(F + WIDTH * 16, 16, 16, 0);
+	Compress(F + WIDTH * 16 + 16, 16, 16, 0);
+	Compress(F + WIDTH * 16 + 32, 16, 16, 0);
+	Compress(F + WIDTH * 32, 16, 16, 0);
+	Compress(F + WIDTH * 32 + 16, 16, 16, 0);
+	Compress(F + WIDTH * 32 + 32, 16, 16, 0);
+	BigClear();
+	while (NumProbs > 0)
+		BigPush(ProbBuf[--NumProbs]);
+	BigWrite(fbuf);
+}