diff --git a/bitutil.c b/bitutil.c
new file mode 100644
index 0000000..45193c4
--- /dev/null
+++ b/bitutil.c
@@ -0,0 +1,137 @@
+/**
+    Copyright (C) powturbo 2013-2015
+    GPL v2 License
+  
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+    - homepage : https://sites.google.com/site/powturbo/
+    - github   : https://github.com/powturbo
+    - twitter  : https://twitter.com/powturbo
+    - email    : powturbo [_AT_] gmail [_DOT_] com
+**/
+//     bitutil.h - "Integer Compression" 
+#include "conf.h" 
+#include "bitutil.h"
+
+#define DELTA(__p,__n, __inc, __start, __act) {\
+  typeof(__p[0]) _x, *_p;\
+  for(_p = __p; _p != __p+(__n&~(4-1)); ) {\
+	_x = (*_p)-__start-__inc; __start = *_p++; __act;\
+	_x = (*_p)-__start-__inc; __start = *_p++; __act;\
+	_x = (*_p)-__start-__inc; __start = *_p++; __act;\
+	_x = (*_p)-__start-__inc; __start = *_p++; __act;\
+  }\
+  while(_p < __p+__n) { \
+    _x = *_p-__start-__inc; __start = *_p++; __act;\
+  }\
+}
+
+#define UNDELTA(__p, __n, __start, __inc) { typeof(__p[0]) *_p;\
+  for(_p = __p; _p != __p+(__n&~(4-1)); ) {\
+    *_p = (__start += (*_p) + __inc); _p++;\
+    *_p = (__start += (*_p) + __inc); _p++;\
+    *_p = (__start += (*_p) + __inc); _p++;\
+    *_p = (__start += (*_p) + __inc); _p++;\
+  }\
+  while(_p < __p+__n) { *_p = (__start += (*_p) + __inc); _p++; }\
+}
+
+unsigned bitdelta32(unsigned *in, unsigned n, unsigned *out, unsigned start, unsigned inc) {
+    #ifdef __SSE2__
+  unsigned *ip,b,*op = out; 
+  __m128i bv = _mm_setzero_si128(), sv = _mm_set1_epi32(start), cv = _mm_set1_epi32(inc), dv;
+  for(ip = in; ip != in+(n&~(4-1)); ip += 4) { 
+    __m128i iv = _mm_loadu_si128((__m128i *)ip); 
+	bv = _mm_or_si128(bv, dv = _mm_sub_epi32(DELTAV(iv,sv),cv)); 
+	sv = iv; 
+	_mm_storeu_si128((__m128i *)op, dv); 
+	op += 4; 
+  }
+  start = (unsigned)_mm_cvtsi128_si32(_mm_srli_si128(sv,12));
+  HOR(bv, b);
+  while(ip < in+n) { unsigned x = *ip-start-inc; start = *ip++; b |= x; *op++ = x; }
+    #else
+  typeof(in[0]) b = 0,*op = out; DELTA(in, n, inc, start, b |= _x;*op++ = _x);
+    #endif
+  return bsr32(b);
+}
+
+unsigned bitd32(unsigned *in, unsigned n, unsigned start) {
+    #ifdef __SSE2__
+  unsigned *ip,b; __m128i bv = _mm_setzero_si128(), sv = _mm_set1_epi32(start);
+  for(ip = in; ip != in+(n&~(4-1)); ip += 4) { 
+    __m128i iv = _mm_loadu_si128((__m128i *)ip); 
+	bv = _mm_or_si128(bv, DELTAV(iv,sv)); 
+	sv = iv; 
+  }
+  
+  start = (unsigned)_mm_cvtsi128_si32(_mm_srli_si128(sv,12));
+  HOR(bv, b);
+  while(ip < in+n) { 
+    unsigned x = *ip-start; 
+	start = *ip++; 
+	b |= x; 
+  }
+    #else
+  typeof(in[0]) b = 0; DELTA(in,n, 0, start, b |= _x);
+    #endif
+  return bsr32(b); 
+}
+
+unsigned bitd132(unsigned *in, unsigned n, unsigned start) {
+    #ifdef __SSE2__
+  unsigned *ip,b; __m128i bv = _mm_setzero_si128(), sv = _mm_set1_epi32(start), cv = _mm_set1_epi32(1);
+  for(ip = in; ip != in+(n&~(4-1)); ip += 4) { 
+    __m128i iv = _mm_loadu_si128((__m128i *)ip); 
+	bv = _mm_or_si128(bv, _mm_sub_epi32(DELTAV(iv,sv),cv)); 
+	sv = iv; 
+  }
+  
+  start = (unsigned)_mm_cvtsi128_si32(_mm_srli_si128(sv,12));
+  HOR(bv, b);
+  while(ip < in+n) { 
+    unsigned x = *ip-start-1; 
+	start = *ip++; 
+	b |= x; 
+  }
+    #else
+  typeof(in[0]) b = 0; DELTA(in, n, 1, start, b |= _x);
+	#endif
+  return bsr32(b); 
+}
+
+void bitund32( unsigned *p, unsigned n, unsigned x) { UNDELTA(p, n, x, 0); }
+
+void bitund132(unsigned *p, unsigned n, unsigned x) { 
+    #ifdef __SSE2__
+  __m128i sv = _mm_set1_epi32(x), cv = _mm_set_epi32(4,3,2,1);
+  unsigned *ip;
+  for(ip = p; ip != p+(n&~(4-1)); ) {
+    __m128i v =  _mm_loadu_si128((__m128i *)ip); 
+	VSCANI(v, sv, cv); 
+	_mm_storeu_si128((__m128i *)ip, sv); 
+	ip += 4;
+  }
+  x = (unsigned)_mm_cvtsi128_si32(_mm_srli_si128(sv,12));
+  while(ip < p+n) { 
+    *ip = (x += (*ip) + 1); 
+	ip++; 
+  }
+    #else
+  UNDELTA(p, n, x, 1); 
+    #endif
+}
+
+void bitundx32(unsigned *p, unsigned n, unsigned x, unsigned inc) { UNDELTA(p, n, x, inc); }