1 files changed, 81 insertions, 0 deletions
diff --git a/Imaging/libImaging/XbmDecode.c b/Imaging/libImaging/XbmDecode.c
new file mode 100644
index 0000000..4819889
--- /dev/null
+++ b/Imaging/libImaging/XbmDecode.c
@@ -0,0 +1,81 @@
+/*
+ * The Python Imaging Library.
+ * $Id: XbmDecode.c 2134 2004-10-06 08:55:20Z fredrik $
+ *
+ * decoder for XBM hex image data
+ *
+ * history:
+ *	96-04-13 fl	Created
+ *
+ * Copyright (c) Fredrik Lundh 1996.
+ * Copyright (c) Secret Labs AB 1997.
+ *
+ * See the README file for information on usage and redistribution.
+ */
+
+
+#include "Imaging.h"
+
+#define	HEX(v) ((v >= '0' && v <= '9') ? v - '0' :\
+		(v >= 'a' && v <= 'f') ? v - 'a' + 10 :\
+		(v >= 'A' && v <= 'F') ? v - 'A' + 10 : 0)
+
+int
+ImagingXbmDecode(Imaging im, ImagingCodecState state, UINT8* buf, int bytes)
+{
+    enum { BYTE = 1, SKIP };
+
+    UINT8* ptr;
+
+    if (!state->state)
+	state->state = SKIP;
+
+    ptr = buf;
+
+    for (;;) {
+
+	if (state->state == SKIP) {
+
+	    /* Skip forward until next 'x' */
+
+	    while (bytes > 0) {
+		if (*ptr == 'x')
+		    break;
+		ptr++;
+		bytes--;
+	    }
+
+	    if (bytes == 0)
+		return ptr - buf;
+
+	    state->state = BYTE;
+
+	}
+
+	if (bytes < 3)
+	    return ptr - buf;
+
+	state->buffer[state->x] = (HEX(ptr[1])<<4) + HEX(ptr[2]);
+
+	if (++state->x >= state->bytes) {
+
+	    /* Got a full line, unpack it */
+	    state->shuffle((UINT8*) im->image[state->y], state->buffer,
+			   state->xsize);
+
+	    state->x = 0;
+
+	    if (++state->y >= state->ysize) {
+		/* End of file (errcode = 0) */
+		return -1;
+	    }
+	}
+
+	ptr += 3;
+	bytes -= 3;
+
+	state->state = SKIP;
+
+    }
+
+}