diff --git a/src/HTMLRenderer/TextLineBuffer.h b/src/HTMLRenderer/TextLineBuffer.h
new file mode 100644
index 0000000..491804a
--- /dev/null
+++ b/src/HTMLRenderer/TextLineBuffer.h
@@ -0,0 +1,77 @@
+#ifndef TEXTLINEBUFFER_H__
+#define TEXTLINEBUFFER_H__
+
+#include <iostream>
+#include <vector>
+
+namespace pdf2htmlEX {
+
+class HTMLRenderer::TextLineBuffer
+{
+public:
+    TextLineBuffer (HTMLRenderer * renderer) : renderer(renderer) { }
+
+    class State {
+        public:
+            void begin(std::ostream & out, const State * prev_state);
+            void end(std::ostream & out) const;
+            void hash(void);
+            int diff(const State & s) const;
+
+            enum {
+                FONT_ID,
+                FONT_SIZE_ID,
+                COLOR_ID,
+                LETTER_SPACE_ID,
+                WORD_SPACE_ID,
+                RISE_ID,
+
+                ID_COUNT
+            };
+
+            long long ids[ID_COUNT];
+
+            double ascent;
+            double descent;
+            double draw_font_size;
+
+            size_t start_idx; // index of the first Text using this state
+            // for optimzation
+            long long hash_value;
+            bool need_close;
+
+            static const char * format_str; // class names for each id
+    };
+
+
+    class Offset {
+        public:
+            size_t start_idx; // should put this idx before text[start_idx];
+            double width;
+    };
+
+    void reset(GfxState * state);
+    void append_unicodes(const Unicode * u, int l);
+    void append_offset(double width);
+    void append_state(void);
+    void flush(void);
+
+private:
+    // retrieve state from renderer
+    void set_state(State & state);
+
+    HTMLRenderer * renderer;
+
+    double x, y;
+    long long tm_id;
+
+    std::vector<State> states;
+    std::vector<Offset> offsets;
+    std::vector<Unicode> text;
+
+    // for flush
+    std::vector<State*> stack;
+};
+
+} // namespace pdf2htmlEX
+#endif //TEXTLINEBUFFER_H__