diff --git a/code/base/test_base.cpp b/code/base/test_base.cpp
index 050d3d3..69bdef1 100644
--- a/code/base/test_base.cpp
+++ b/code/base/test_base.cpp
@@ -876,10 +876,25 @@ public:
 		{
 			return SCANNER_ERR_DATA_DAMAGED;
 		}
-		unsigned int len = 0;
-		int ret = SCANNER_ERR_OK;
+		wchar_t* p = (wchar_t*)data;
+		std::string str;
+		int ret = SCANNER_ERR_OK,
+			dpi = 0;
+		unsigned int len = sizeof(int);
+		size_t strl = 0;
+		ret = wchar_to_char(str, p, &strl);
+		if (ret == ERROR_INSUFFICIENT_BUFFER)
+		{
+			str.resize(strl);
+			ret = wchar_to_char(str, p, &strl);
+		}
+		if (str.empty())
+		{
+			return SCANNER_ERR_DATA_DAMAGED;
+		}
+		dpi = atoi(str.c_str());
+		ret = helper_->io_control(IO_CTRL_CODE_SET_DPI, &dpi, &len);
 
-		ret = helper_->io_control(IO_CTRL_CODE_SET_DPI, data, &len);
 		if (ret != SCANNER_ERR_OK)
 		{
 			return -1;
@@ -893,12 +908,29 @@ public:
 		{
 			return SCANNER_ERR_DATA_DAMAGED;
 		}
-		int ret = SCANNER_ERR_OK, 
-			val = 0;
+		wchar_t* p = (wchar_t*)data;
+		std::string str;
+		
+
+		int ret = SCANNER_ERR_OK,
+			val = 0, 
+			dpi = 0;
 		SANE_Bool type = true;
 		unsigned int len = sizeof(SANE_Bool),
 					llen = sizeof(int);
-		ret = helper_->io_control(IO_CTRL_CODE_SET_DPI, &data, &len);
+		size_t strl = 0;
+		ret = wchar_to_char(str, p, &strl);
+		if (ret == ERROR_INSUFFICIENT_BUFFER)
+		{
+			str.resize(strl);
+			ret = wchar_to_char(str, p, &strl);
+		}
+		if (str.empty())
+		{
+			return SCANNER_ERR_DATA_DAMAGED;
+		}
+		dpi = atoi(str.c_str());
+		ret = helper_->io_control(IO_CTRL_CODE_SET_DPI, &dpi, &llen);
 
 		ret = helper_->io_control(IO_CTRL_CODE_SET_DISTORTION_IMAGE, &type, &len);
 		if (ret != SCANNER_ERR_OK)