From: Robert Spalek <robert@ucw.cz>
Date: Mon, 14 Jun 2004 10:24:56 +0000 (+0000)
Subject: updated the maximum prolong-factor
X-Git-Tag: holmes-import~1056
X-Git-Url: http://mj.ucw.cz/gitweb/?a=commitdiff_plain;h=b1fecd022eb9651c98d8692eb0f8683e54507977;p=libucw.git

updated the maximum prolong-factor
---

diff --git a/lib/lizard.h b/lib/lizard.h
index 25ba4bce..1929cffb 100644
--- a/lib/lizard.h
+++ b/lib/lizard.h
@@ -10,18 +10,18 @@
 #define	LIZZARD_NEEDS_CHARS	8
   /* The compression routine needs input buffer 8 characters longer, because it
    * does not check the input bounds all the time.  */
-#define	LIZZARD_MAX_MULTIPLY	65LL/64
+#define	LIZZARD_MAX_MULTIPLY	23./22
 #define	LIZZARD_MAX_ADD		4
   /* In the worst case, the compressed file will not be longer than its
-   * original length * 65/64 + 4.
+   * original length * 23/22 + 4.
    *
    * The additive constant is for EOF and the header of the file.
    *
-   * The multiplicative constant 129/128 comes from an incompressible string of
-   * length 256 that requires a 2-byte header.  However, if longer strings get
-   * interrupted by a sequence of length 3 compressed into 2 characters, the
-   * overlap is sligtly bigger.
-   * TODO: check */
+   * The multiplicative constant comes from 19-byte incompressible string
+   * followed by a 3-sequence that can be compressed into 2-byte link.  This
+   * breaks the copy-mode and it needs to be restarted with a new header.  The
+   * total length is 2(header) + 2(link) + 19(string) = 23.
+   */
 
 int lizzard_compress(byte *in, uns in_len, byte *out);
 int lizzard_decompress(byte *in, byte *out);