diff --git a/uppdev/BitStream/BitStream.cpp b/uppdev/BitStream/BitStream.cpp
new file mode 100644
index 000000000..b14ea94b5
--- /dev/null
+++ b/uppdev/BitStream/BitStream.cpp
@@ -0,0 +1,91 @@
+#include <Core/Core.h>
+
+using namespace Upp;
+
+class BitsOut {
+	Stream *stream;
+
+	byte  buffer;
+	int   left;
+	
+	void  Out()                          { stream->Put(buffer); left = 8; buffer = 0; }
+	void  Flush()                        { if(left != 8) { Out(); } }
+
+public:
+	void Start(Stream& s)                { Finish(); stream = &s; left = 8; buffer = 0; }
+	void Finish()                        { if(stream) Flush(); stream = NULL; }
+	
+	void Put(dword w, int bits);
+	void Put(bool bit)                   { Put(bit, 1); }
+	
+	BitsOut()                            { stream = NULL; }
+	BitsOut(Stream& s)                   { Start(s); }
+	~BitsOut()                           { Finish(); }
+};
+
+void BitsOut::Put(dword w, int bits)
+{
+	ASSERT(bits >= 0 && bits <= 32);
+	while(bits) {
+		int q = min(left, bits);
+		bits -= q;
+		left -= q;
+		buffer |= w >> bits << left;
+		if(left == 0)
+			Out();
+	}
+}
+
+class BitsIn {
+	Stream *stream;
+
+	byte  buffer;
+	int   left;
+	
+	void  In()                           { buffer = stream->Get(); left = 8; }
+
+public:
+	void Start(Stream& s)                { stream = &s; left = 0; }
+	
+	dword Get(int bits);
+	bool  Get()                          { return Get(1); }
+	
+	BitsIn()                             { stream = NULL; }
+	BitsIn(Stream& s)                    { Start(s); }
+};
+
+dword BitsIn::Get(int bits)
+{
+	dword result = 0;
+	while(bits) {
+		if(left == 0)
+			In();
+		int q = min(bits, left);
+		left -= q;
+		bits -= q;
+		result = (result << q) | ((buffer >> left) & (0xff << q >> 8));
+	}
+	return result;
+}
+
+CONSOLE_APP_MAIN
+{
+	StringStream ss;
+	BitsOut out;
+	out.Start(ss);
+	out.Put(0x123, 12);
+	out.Put(1234, 12);
+	out.Put(12345, 15);
+	out.Put(4, 3);
+	out.Put(1);
+	out.Put(0);
+	out.Put(1);
+	out.Put(1);
+	out.Finish();
+	ss.Seek(0);
+	BitsIn in(ss);
+	DUMP(in.Get(12));
+	DUMP(in.Get(12));
+	DUMP(in.Get(15));
+	DUMP(in.Get(3));
+}
diff --git a/uppdev/BitStream/BitStream.upp b/uppdev/BitStream/BitStream.upp
new file mode 100644
index 000000000..8a48cce12
--- /dev/null
+++ b/uppdev/BitStream/BitStream.upp
@@ -0,0 +1,9 @@
+uses
+	Core;
+
+file
+	BitStream.cpp;
+
+mainconfig
+	"" = "SSE2";
+
diff --git a/uppdev/BitStream/init b/uppdev/BitStream/init
new file mode 100644
index 000000000..bab5585a3
--- /dev/null
+++ b/uppdev/BitStream/init
@@ -0,0 +1,4 @@
+#ifndef _BitStream_icpp_init_stub
+#define _BitStream_icpp_init_stub
+#include "Core/init"
+#endif