diff --git a/build/windows/HGTest/HGTestDlg.cpp b/build/windows/HGTest/HGTestDlg.cpp
index 90e5934e..584545da 100644
--- a/build/windows/HGTest/HGTestDlg.cpp
+++ b/build/windows/HGTest/HGTestDlg.cpp
@@ -129,8 +129,7 @@ BOOL CHGTestDlg::OnInitDialog()
 #ifdef USE_SANE
 	HGSane_CreateManager("sane.dll", &m_saneMgr);
 #else
-	HGTwain_LoadDSM(&m_dsm);
-	HGTwain_OpenDSM(m_dsm, m_hWnd);
+	HGTwain_CreateDSM(m_hWnd, &m_dsm);
 #endif
 
 	return TRUE;  // 除非将焦点设置到控件，否则返回 TRUE
@@ -207,11 +206,12 @@ void CHGTestDlg::OnBnClickedButton1()
 		return;
 	}
 
-	HGTwain_SelectDS(m_dsm, &m_ds);
-	if (NULL != m_ds)
+	HGTwain_OpenSelectedDS(m_dsm, &m_ds);
+	HGResult ret = HGTwain_EnableDS(m_ds, HGTRUE, m_hWnd, DSEventCallback, this, DSImageCallback, this);
+	if (HGBASE_ERR_OK != ret)
 	{
-		HGTwain_OpenDS(m_ds);
-		HGTwain_EnableDS(m_ds, HGTRUE, m_hWnd, DSEventCallback, this);
+		HGTwain_CloseDS(m_ds);
+		m_ds = NULL;
 	}
 #endif
 }
@@ -237,50 +237,25 @@ void HGAPI CHGTestDlg::DeviceEventCallback(HGSaneDevice dev, HGUInt error, const
 void HGAPI CHGTestDlg::DeviceImageCallback(HGSaneDevice dev, HGImage image, HGPointer param)
 {
 	CHGTestDlg* p = (CHGTestDlg*)param;
-
 	CStringA strName;
 	strName.Format("D:\\HGTest_%u.jpg", p->m_idx++);
 	HGImgFmt_SaveImage(image, 0, NULL, strName);
 }
 #else
-void CHGTestDlg::DSEventCallback(HGTwainDS ds, HGUInt event, HGPointer param)
+void CHGTestDlg::DSEventCallback(HGTwainDS ds, HGUInt error, const HGChar* errInfo, HGPointer param)
 {
 	CHGTestDlg* p = (CHGTestDlg*)param;
-	if (HGTWAIN_DSEVENT_XFERREADY == event)
-	{
-		while (1)
-		{
-			HGImage image = NULL;
-			HGTwain_ImageNativeXfer(p->m_ds, 0, 0, &image);
-			CStringA strName;
-			strName.Format("D:\\Twain_%u.jpg", p->m_idx++);
-			HGImgFmt_SaveImage(image, 0, NULL, strName);
-			HGBase_DestroyImage(image);
-
-			HGUInt count = 0;
-			HGTwain_EndXfer(p->m_ds, &count);
-			if (0 == count)
-			{
-				break;
-			}
-		}
-
-		HGTwain_Reset(p->m_ds);
-	}
-	else if (HGTWAIN_DSEVENT_CLOSEDSREQ == event)
-	{
-		HGTwain_CloseDS(p->m_ds);
-		p->m_ds = NULL;
-	}
-	else if (HGTWAIN_DSEVENT_CLOSEDSOK == event)
-	{
-		HGTwain_CloseDS(p->m_ds);
-		p->m_ds = NULL;
-	}
+	::PostMessage(p->m_hWnd, 2000, 0, 0);
+}
+void HGAPI CHGTestDlg::DSImageCallback(HGTwainDS ds, HGImage image, HGPointer param)
+{
+	CHGTestDlg* p = (CHGTestDlg*)param;
+	CStringA strName;
+	strName.Format("D:\\HGTest_%u.jpg", p->m_idx++);
+	HGImgFmt_SaveImage(image, 0, NULL, strName);
 }
 #endif
 
-
 LRESULT CHGTestDlg::WindowProc(UINT message, WPARAM wParam, LPARAM lParam)
 {
 	if (2000 == message)
@@ -288,6 +263,9 @@ LRESULT CHGTestDlg::WindowProc(UINT message, WPARAM wParam, LPARAM lParam)
 #ifdef USE_SANE
 		HGSane_CloseDevice(m_saneDev);
 		m_saneDev = NULL;
+#else
+		HGTwain_CloseDS(m_ds);
+		m_ds = NULL;
 #endif
 	}
 
diff --git a/build/windows/HGTest/HGTestDlg.h b/build/windows/HGTest/HGTestDlg.h
index 954ffe6a..9edb035b 100644
--- a/build/windows/HGTest/HGTestDlg.h
+++ b/build/windows/HGTest/HGTestDlg.h
@@ -30,7 +30,8 @@ protected:
 #else
 	HGTwainDSM m_dsm;
 	HGTwainDS m_ds;
-	static void HGAPI DSEventCallback(HGTwainDS ds, HGUInt event, HGPointer param);
+	static void HGAPI DSEventCallback(HGTwainDS ds, HGUInt error, const HGChar* errInfo, HGPointer param);
+	static void HGAPI DSImageCallback(HGTwainDS ds, HGImage image, HGPointer param);
 #endif
 
 // 实现
diff --git a/build/windows/HGTwainUser/HGTwainUser.def b/build/windows/HGTwainUser/HGTwainUser.def
index b343909c..0806de23 100644
--- a/build/windows/HGTwainUser/HGTwainUser.def
+++ b/build/windows/HGTwainUser/HGTwainUser.def
@@ -2,21 +2,14 @@ LIBRARY
 
 EXPORTS
 
-HGTwain_LoadDSM
-HGTwain_UnloadDSM
-HGTwain_OpenDSM
-HGTwain_CloseDSM
-HGTwain_GetDSList
-HGTwain_GetDefaultDS
-HGTwain_SelectDS
+HGTwain_CreateDSM
+HGTwain_DestroyDSM
+HGTwain_GetDSCount
 HGTwain_GetDSName
 HGTwain_OpenDS
+HGTwain_OpenDefaultDS
+HGTwain_OpenSelectedDS
 HGTwain_CloseDS
-HGTwain_SetCapability
-HGTwain_GetCapability
 HGTwain_EnableDSUIOnly
 HGTwain_EnableDS
 HGTwain_DisableDS
-HGTwain_ImageNativeXfer
-HGTwain_EndXfer
-HGTwain_Reset
diff --git a/modules/sane_user/HGSane.h b/modules/sane_user/HGSane.h
index 33f3fbcc..20104823 100644
--- a/modules/sane_user/HGSane.h
+++ b/modules/sane_user/HGSane.h
@@ -10,7 +10,7 @@
 HG_DECLARE_HANDLE(HGSaneManager);
 HG_DECLARE_HANDLE(HGSaneDevice);
 
-/* Sane设备回调
+/* Sane回调
 */
 typedef void (HGAPI* HGSane_DeviceEventFunc)(HGSaneDevice dev, HGUInt error, const HGChar *errInfo, HGPointer param);
 typedef void (HGAPI* HGSane_DeviceImageFunc)(HGSaneDevice dev, HGImage image, HGPointer param);
diff --git a/modules/sane_user/HGSaneImpl.cpp b/modules/sane_user/HGSaneImpl.cpp
index 87dc74f0..eecdc5cb 100644
--- a/modules/sane_user/HGSaneImpl.cpp
+++ b/modules/sane_user/HGSaneImpl.cpp
@@ -26,10 +26,7 @@ HGSaneManagerImpl::~HGSaneManagerImpl()
 
 HGResult HGSaneManagerImpl::Create(const HGChar* sanePath)
 {
-	if (NULL != m_dll)
-	{
-		return HGBASE_ERR_FAIL;
-	}
+	assert(NULL == m_dll);
 
 	HGResult ret = HGBase_CreateDll(sanePath, &m_dll);
 	if (HGBASE_ERR_OK != ret)
@@ -57,18 +54,16 @@ HGResult HGSaneManagerImpl::Create(const HGChar* sanePath)
 
 HGResult HGSaneManagerImpl::Destroy()
 {
+	assert(NULL != m_dll);
+
 	if (!m_listDeviceImpl.empty())
 	{
 		return HGBASE_ERR_FAIL;
 	}
 
-	if (NULL != m_dll)
-	{
-		m_f_sane_exit();
-		HGBase_DestroyDll(m_dll);
-		m_dll = NULL;
-	}
-
+	m_f_sane_exit();
+	HGBase_DestroyDll(m_dll);
+	m_dll = NULL;
 	return HGBASE_ERR_OK;
 }
 
@@ -256,10 +251,7 @@ HGSaneDeviceImpl::~HGSaneDeviceImpl()
 
 HGResult HGSaneDeviceImpl::Open(const HGChar* devName, HGChar* errInfo, HGUInt errInfoLen)
 {
-	if (NULL != m_devHandle)
-	{
-		return HGBASE_ERR_FAIL;
-	}
+	assert(NULL == m_devHandle);
 
 	if (NULL == devName)
 	{
@@ -289,10 +281,7 @@ HGResult HGSaneDeviceImpl::Open(const HGChar* devName, HGChar* errInfo, HGUInt e
 
 HGResult HGSaneDeviceImpl::Close()
 {
-	if (NULL == m_devHandle)
-	{
-		return HGBASE_ERR_FAIL;
-	}
+	assert(NULL != m_devHandle);
 
 	Stop();
 	m_mgrImpl->m_f_sane_close(m_devHandle);
diff --git a/modules/twain_user/HGTwain.cpp b/modules/twain_user/HGTwain.cpp
index a4f5b3e4..a3e93af9 100644
--- a/modules/twain_user/HGTwain.cpp
+++ b/modules/twain_user/HGTwain.cpp
@@ -1,7 +1,7 @@
 #include "HGTwain.h"
 #include "HGTwainImpl.hpp"
 
-HGResult HGAPI HGTwain_LoadDSM(HGTwainDSM* dsm)
+HGResult HGAPI HGTwain_CreateDSM(HWND hwnd, HGTwainDSM* dsm)
 {
 	if (NULL == dsm)
 	{
@@ -9,7 +9,7 @@ HGResult HGAPI HGTwain_LoadDSM(HGTwainDSM* dsm)
 	}
 
 	HGTwainDSMImpl* twainDSMImpl = new HGTwainDSMImpl;
-	HGResult ret = twainDSMImpl->LoadDSM();
+	HGResult ret = twainDSMImpl->Create(hwnd);
 	if (HGBASE_ERR_OK != ret)
 	{
 		delete twainDSMImpl;
@@ -20,7 +20,7 @@ HGResult HGAPI HGTwain_LoadDSM(HGTwainDSM* dsm)
 	return HGBASE_ERR_OK;
 }
 
-HGResult HGAPI HGTwain_UnloadDSM(HGTwainDSM dsm)
+HGResult HGAPI HGTwain_DestroyDSM(HGTwainDSM dsm)
 {
 	if (NULL == dsm)
 	{
@@ -28,7 +28,7 @@ HGResult HGAPI HGTwain_UnloadDSM(HGTwainDSM dsm)
 	}
 
 	HGTwainDSMImpl* twainDSMImpl = (HGTwainDSMImpl*)dsm;
-	HGResult ret = twainDSMImpl->UnloadDSM();
+	HGResult ret = twainDSMImpl->Destroy();
 	if (HGBASE_ERR_OK != ret)
 	{
 		return ret;
@@ -38,7 +38,7 @@ HGResult HGAPI HGTwain_UnloadDSM(HGTwainDSM dsm)
 	return HGBASE_ERR_OK;
 }
 
-HGResult HGAPI HGTwain_OpenDSM(HGTwainDSM dsm, HWND hwnd)
+HGResult HGAPI HGTwain_GetDSCount(HGTwainDSM dsm, HGUInt* count)
 {
 	if (NULL == dsm)
 	{
@@ -46,10 +46,10 @@ HGResult HGAPI HGTwain_OpenDSM(HGTwainDSM dsm, HWND hwnd)
 	}
 
 	HGTwainDSMImpl* twainDSMImpl = (HGTwainDSMImpl*)dsm;
-	return twainDSMImpl->OpenDSM(hwnd);
+	return twainDSMImpl->GetDSCount(count);
 }
 
-HGResult HGAPI HGTwain_CloseDSM(HGTwainDSM dsm)
+HGResult HGAPI HGTwain_GetDSName(HGTwainDSM dsm, HGUInt index, HGChar* name, HGUInt maxLen)
 {
 	if (NULL == dsm)
 	{
@@ -57,10 +57,10 @@ HGResult HGAPI HGTwain_CloseDSM(HGTwainDSM dsm)
 	}
 
 	HGTwainDSMImpl* twainDSMImpl = (HGTwainDSMImpl*)dsm;
-	return twainDSMImpl->CloseDSM();
+	return twainDSMImpl->GetDSName(index, name, maxLen);
 }
 
-HGResult HGAPI HGTwain_GetDSList(HGTwainDSM dsm, HGTwainDS* ds, HGUInt* size)
+HGResult HGAPI HGTwain_OpenDS(HGTwainDSM dsm, HGUInt index, HGTwainDS* ds)
 {
 	if (NULL == dsm)
 	{
@@ -68,10 +68,18 @@ HGResult HGAPI HGTwain_GetDSList(HGTwainDSM dsm, HGTwainDS* ds, HGUInt* size)
 	}
 
 	HGTwainDSMImpl* twainDSMImpl = (HGTwainDSMImpl*)dsm;
-	return twainDSMImpl->GetDSList((HGTwainDSImpl**)ds, size);
+	class HGTwainDSImpl* dsImpl = NULL;
+	HGResult ret = twainDSMImpl->OpenDS(index, &dsImpl);
+	if (HGBASE_ERR_OK != ret)
+	{
+		return ret;
+	}
+
+	*ds = (HGTwainDS)dsImpl;
+	return HGBASE_ERR_OK;
 }
 
-HGResult HGAPI HGTwain_GetDefaultDS(HGTwainDSM dsm, HGTwainDS* ds)
+HGResult HGAPI HGTwain_OpenDefaultDS(HGTwainDSM dsm, HGTwainDS* ds)
 {
 	if (NULL == dsm)
 	{
@@ -79,10 +87,18 @@ HGResult HGAPI HGTwain_GetDefaultDS(HGTwainDSM dsm, HGTwainDS* ds)
 	}
 
 	HGTwainDSMImpl* twainDSMImpl = (HGTwainDSMImpl*)dsm;
-	return twainDSMImpl->GetDefaultDS((HGTwainDSImpl**)ds);
+	class HGTwainDSImpl* dsImpl = NULL;
+	HGResult ret = twainDSMImpl->OpenDefaultDS(&dsImpl);
+	if (HGBASE_ERR_OK != ret)
+	{
+		return ret;
+	}
+
+	*ds = (HGTwainDS)dsImpl;
+	return HGBASE_ERR_OK;
 }
 
-HGResult HGAPI HGTwain_SelectDS(HGTwainDSM dsm, HGTwainDS* ds)
+HGResult HGAPI HGTwain_OpenSelectedDS(HGTwainDSM dsm, HGTwainDS* ds)
 {
 	if (NULL == dsm)
 	{
@@ -90,29 +106,15 @@ HGResult HGAPI HGTwain_SelectDS(HGTwainDSM dsm, HGTwainDS* ds)
 	}
 
 	HGTwainDSMImpl* twainDSMImpl = (HGTwainDSMImpl*)dsm;
-	return twainDSMImpl->SelectDS((HGTwainDSImpl**)ds);
-}
-
-HGResult HGAPI HGTwain_GetDSName(HGTwainDS ds, HGChar* name, HGUInt maxLen)
-{
-	if (NULL == ds)
+	class HGTwainDSImpl* dsImpl = NULL;
+	HGResult ret = twainDSMImpl->OpenSelectedDS(&dsImpl);
+	if (HGBASE_ERR_OK != ret)
 	{
-		return HGBASE_ERR_INVALIDARG;
+		return ret;
 	}
 
-	HGTwainDSImpl* twainDSImpl = (HGTwainDSImpl*)ds;
-	return twainDSImpl->GetName(name, maxLen);
-}
-
-HGResult HGAPI HGTwain_OpenDS(HGTwainDS ds)
-{
-	if (NULL == ds)
-	{
-		return HGBASE_ERR_INVALIDARG;
-	}
-
-	HGTwainDSImpl* twainDSImpl = (HGTwainDSImpl*)ds;
-	return twainDSImpl->Open();
+	*ds = (HGTwainDS)dsImpl;
+	return HGBASE_ERR_OK;
 }
 
 HGResult HGAPI HGTwain_CloseDS(HGTwainDS ds)
@@ -126,7 +128,7 @@ HGResult HGAPI HGTwain_CloseDS(HGTwainDS ds)
 	return twainDSImpl->Close();
 }
 
-HGResult HGAPI HGTwain_SetCapability(HGTwainDS ds, HGUInt cap, HGInt value)
+HGResult HGAPI HGTwain_EnableDSUIOnly(HGTwainDS ds, HGBool showUI, HWND parent, HGDSEventFunc eventFunc, HGPointer eventParam)
 {
 	if (NULL == ds)
 	{
@@ -134,10 +136,11 @@ HGResult HGAPI HGTwain_SetCapability(HGTwainDS ds, HGUInt cap, HGInt value)
 	}
 
 	HGTwainDSImpl* twainDSImpl = (HGTwainDSImpl*)ds;
-	return twainDSImpl->SetCap(cap, value);
+	return twainDSImpl->EnableUIOnly(showUI, parent, eventFunc, eventParam);
 }
 
-HGResult HGAPI HGTwain_GetCapability(HGTwainDS ds, HGUInt cap, HGInt* value)
+HGResult HGAPI HGTwain_EnableDS(HGTwainDS ds, HGBool showUI, HWND parent, HGDSEventFunc eventFunc, HGPointer eventParam,
+	HGDSImageFunc imageFunc, HGPointer imageParam)
 {
 	if (NULL == ds)
 	{
@@ -145,29 +148,7 @@ HGResult HGAPI HGTwain_GetCapability(HGTwainDS ds, HGUInt cap, HGInt* value)
 	}
 
 	HGTwainDSImpl* twainDSImpl = (HGTwainDSImpl*)ds;
-	return twainDSImpl->GetCap(cap, value);
-}
-
-HGResult HGAPI HGTwain_EnableDSUIOnly(HGTwainDS ds, HGBool showUI, HWND parent, HGDSEventFunc func, HGPointer param)
-{
-	if (NULL == ds)
-	{
-		return HGBASE_ERR_INVALIDARG;
-	}
-
-	HGTwainDSImpl* twainDSImpl = (HGTwainDSImpl*)ds;
-	return twainDSImpl->EnableUIOnly(showUI, parent, func, param);
-}
-
-HGResult HGAPI HGTwain_EnableDS(HGTwainDS ds, HGBool showUI, HWND parent, HGDSEventFunc func, HGPointer param)
-{
-	if (NULL == ds)
-	{
-		return HGBASE_ERR_INVALIDARG;
-	}
-
-	HGTwainDSImpl* twainDSImpl = (HGTwainDSImpl*)ds;
-	return twainDSImpl->Enable(showUI, parent, func, param);
+	return twainDSImpl->Enable(showUI, parent, eventFunc, eventParam, imageFunc, imageParam);
 }
 
 HGResult HGAPI HGTwain_DisableDS(HGTwainDS ds)
@@ -179,37 +160,4 @@ HGResult HGAPI HGTwain_DisableDS(HGTwainDS ds)
 
 	HGTwainDSImpl* twainDSImpl = (HGTwainDSImpl*)ds;
 	return twainDSImpl->Disable();
-}
-
-HGResult HGAPI HGTwain_ImageNativeXfer(HGTwainDS ds, HGUInt type, HGUInt origin, HGImage* image)
-{
-	if (NULL == ds)
-	{
-		return HGBASE_ERR_INVALIDARG;
-	}
-
-	HGTwainDSImpl* twainDSImpl = (HGTwainDSImpl*)ds;
-	return twainDSImpl->ImageNativeXfer(type, origin, image);
-}
-
-HGResult HGAPI HGTwain_EndXfer(HGTwainDS ds, HGUInt* count)
-{
-	if (NULL == ds)
-	{
-		return HGBASE_ERR_INVALIDARG;
-	}
-
-	HGTwainDSImpl* twainDSImpl = (HGTwainDSImpl*)ds;
-	return twainDSImpl->EndXfer(count);
-}
-
-HGResult HGAPI HGTwain_Reset(HGTwainDS ds)
-{
-	if (NULL == ds)
-	{
-		return HGBASE_ERR_INVALIDARG;
-	}
-
-	HGTwainDSImpl* twainDSImpl = (HGTwainDSImpl*)ds;
-	return twainDSImpl->Reset();
 }
\ No newline at end of file
diff --git a/modules/twain_user/HGTwain.h b/modules/twain_user/HGTwain.h
index b9b1e42d..2e3ed66b 100644
--- a/modules/twain_user/HGTwain.h
+++ b/modules/twain_user/HGTwain.h
@@ -9,199 +9,32 @@
 HG_DECLARE_HANDLE(HGTwainDSM);
 HG_DECLARE_HANDLE(HGTwainDS);
 
-/* 能力 */
-#define HGTWAIN_DSCAP_DUPLEX		1L
-#define HGTWAIN_DSCAP_DUPLEXENABLED	2L
-#define HGTWAIN_DSCAP_XFERCOUNT		3L
-
-/* 未知事件, 可能是该库未进行处理的事件 */
-#define HGTWAIN_DSEVENT_UNKNOWN		0L
-#define HGTWAIN_DSEVENT_XFERREADY	1L
-#define HGTWAIN_DSEVENT_CLOSEDSREQ	2L
-#define HGTWAIN_DSEVENT_CLOSEDSOK	3L
-
-/* twain事件回调
-* 参数:
-* 1) ds: in, DS句柄
-* 2) event: in, 事件, 参见HGTWAIN_DSEVENT_*
-* 3) param: in, 回调参数
-* 说明:
-* 1) 如果event为HGTWAIN_EVENT_XFERREADY, TWAIN状态从5变为6
-* 2) 如果event为HGTWAIN_EVENT_CLOSEDSREQ, 表示需要关闭该DS
+/* ds回调
 */
-typedef void (HGAPI *HGDSEventFunc)(HGTwainDS ds, HGUInt event, HGPointer param);
+typedef void (HGAPI *HGDSEventFunc)(HGTwainDS ds, HGUInt error, const HGChar* errInfo, HGPointer param);
+typedef void (HGAPI* HGDSImageFunc)(HGTwainDS ds, HGImage image, HGPointer param);
 
-/* 加载DSM
-* 参数:
-* 1) dsm: out, DSM句柄
-* 说明:
-* 1) 执行此函数后，TWAIN状态从1变为2
-*/
-HGEXPORT HGResult HGAPI HGTwain_LoadDSM(HGTwainDSM *dsm);
+HGEXPORT HGResult HGAPI HGTwain_CreateDSM(HWND hwnd, HGTwainDSM *dsm);
 
-/* 卸载DSM
-* 参数:
-* 1) dsm: in, DSM句柄
-* 说明:
-* 1) 执行此函数后，TWAIN状态从2变为1
-*/
-HGEXPORT HGResult HGAPI HGTwain_UnloadDSM(HGTwainDSM dsm);
+HGEXPORT HGResult HGAPI HGTwain_DestroyDSM(HGTwainDSM dsm);
 
-/* 打开DSM
-* 参数:
-* 1) dsm: in, DSM句柄
-* 说明:
-* 1) 执行此函数后，TWAIN状态从2变为3
-* 2) 调用该函数的线程需要有消息循环
-*/
-HGEXPORT HGResult HGAPI HGTwain_OpenDSM(HGTwainDSM dsm, HWND hwnd);
+HGEXPORT HGResult HGAPI HGTwain_GetDSCount(HGTwainDSM dsm, HGUInt* count);
 
-/* 关闭DSM
-* 参数:
-* 1) dsm: in, DSM句柄
-* 说明:
-* 1) 执行此函数后，TWAIN状态从3变为2
-*/
-HGEXPORT HGResult HGAPI HGTwain_CloseDSM(HGTwainDSM dsm);
+HGEXPORT HGResult HGAPI HGTwain_GetDSName(HGTwainDSM dsm, HGUInt index, HGChar* name, HGUInt maxLen);
 
-/* 获取DS列表
-* 参数:
-* 1) dsm: in, DSM句柄
-* 2) ds: out, DS句柄列表
-* 3) size: in, out, DS句柄列表大小/返回的DS句柄数量
-* 说明:
-* 1) 该函数需要TWAIN状态为3
-* 2) size既作为输入, 也作为输出
-*/
-HGEXPORT HGResult HGAPI HGTwain_GetDSList(HGTwainDSM dsm, HGTwainDS *ds, HGUInt *size);
+HGEXPORT HGResult HGAPI HGTwain_OpenDS(HGTwainDSM dsm, HGUInt index, HGTwainDS *ds);
 
-/* 获取默认的DS
-* 参数:
-* 1) dsm: in, DSM句柄
-* 2) ds: out, DS句柄
-* 说明:
-* 1) 该函数需要TWAIN状态为3
-*/
-HGEXPORT HGResult HGAPI HGTwain_GetDefaultDS(HGTwainDSM dsm, HGTwainDS* ds);
+HGEXPORT HGResult HGAPI HGTwain_OpenDefaultDS(HGTwainDSM dsm, HGTwainDS* ds);
 
-/* 弹出DS选择框，并返回选择的DS
-* 参数:
-* 1) dsm: in, DSM句柄
-* 2) ds: out, DS句柄
-* 说明:
-* 1) 该函数需要TWAIN状态为3
-*/
-HGEXPORT HGResult HGAPI HGTwain_SelectDS(HGTwainDSM dsm, HGTwainDS* ds);
+HGEXPORT HGResult HGAPI HGTwain_OpenSelectedDS(HGTwainDSM dsm, HGTwainDS* ds);
 
-/* 获取DS名称
-* 参数:
-* 1) ds: in, DS句柄
-* 2) name: out, DS名字数据区地址
-* 3) maxLen: in, DS名字数据区长度
-* 说明:
-* 1) 该函数需要TWAIN状态为3
-* 2) size既作为输入, 也作为输出, 返回的size包括空字符
-*/
-HGEXPORT HGResult HGAPI HGTwain_GetDSName(HGTwainDS ds, HGChar *name, HGUInt maxLen);
-
-/* 打开DS
-* 参数:
-* 1) ds: in, DS句柄
-* 说明:
-* 1) 执行此函数后，TWAIN状态从3变为4
-*/
-HGEXPORT HGResult HGAPI HGTwain_OpenDS(HGTwainDS ds);
-
-/* 关闭DS
-* 参数:
-* 1) ds: in, DS句柄
-* 说明:
-* 1) 执行此函数后，TWAIN状态从4变为3
-*/
 HGEXPORT HGResult HGAPI HGTwain_CloseDS(HGTwainDS ds);
 
-/* 设置DS的能力
-* 参数:
-* 1) ds: in, DS句柄
-* 2) cap: in, 能力
-* 3) value: in, 值
-* 说明:
-* 1) 该函数需要TWAIN状态为4
-*/
-HGEXPORT HGResult HGAPI HGTwain_SetCapability(HGTwainDS ds, HGUInt cap, HGInt value);
+HGEXPORT HGResult HGAPI HGTwain_EnableDSUIOnly(HGTwainDS ds, HGBool showUI, HWND parent, HGDSEventFunc eventFunc, HGPointer eventParam);
 
-/* 获取DS的能力
-* 参数:
-* 1) ds: in, DS句柄
-* 2) cap: in, 能力
-* 3) value: out, 值
-* 说明:
-* 1) 该函数需要TWAIN状态为4-7
-*/
-HGEXPORT HGResult HGAPI HGTwain_GetCapability(HGTwainDS ds, HGUInt cap, HGInt* value);
+HGEXPORT HGResult HGAPI HGTwain_EnableDS(HGTwainDS ds, HGBool showUI, HWND parent, HGDSEventFunc eventFunc, HGPointer eventParam,
+	HGDSImageFunc imageFunc, HGPointer imageParam);
 
-/* 启动DS, 仅仅用作参数设置
-* 参数:
-* 1) ds: in, DS句柄
-* 2) showUI: in, 是否显示UI
-* 3) parent: in, 父窗口句柄
-* 4) func: in, 回调函数
-* 5) param: in, 回调参数
-* 说明:
-* 1) 执行此函数后，TWAIN状态从4变为5
-*/
-HGEXPORT HGResult HGAPI HGTwain_EnableDSUIOnly(HGTwainDS ds, HGBool showUI, HWND parent, HGDSEventFunc func, HGPointer param);
-
-/* 启动DS
-* 参数:
-* 1) ds: in, DS句柄
-* 2) showUI: in, 是否显示UI
-* 3) parent: in, 父窗口句柄
-* 4) func: in, 回调函数
-* 5) param: in, 回调参数
-* 说明:
-* 1) 执行此函数后，TWAIN状态从4变为5
-*/
-HGEXPORT HGResult HGAPI HGTwain_EnableDS(HGTwainDS ds, HGBool showUI, HWND parent, HGDSEventFunc func, HGPointer param);
-
-/* 停止DS
-* 参数:
-* 1) ds: in, DS句柄
-* 说明:
-* 1) 执行此函数后，TWAIN状态从5变为4
-*/
 HGEXPORT HGResult HGAPI HGTwain_DisableDS(HGTwainDS ds);
 
-/* 本地传输图像
-* 参数:
-* 1) ds: in, DS句柄
-* 2) type: in, 图像类型
-* 3) origin: in, 图像数据排列方式
-* 4) image: out, 获取的图像
-* 说明:
-* 1) 该函数需要在状态6调用
-* 2) 执行此函数时，TWAIN状态从6变为7
-* 3) 生成的image需要调用HGBase_DestroyImage销毁
-*/
-HGEXPORT HGResult HGAPI HGTwain_ImageNativeXfer(HGTwainDS ds, HGUInt type, HGUInt origin, HGImage *image);
-
-/* 停止本次传输
-* 参数:
-* 1) ds: in, DS句柄
-* 2) count: out, 还剩下的未传输的图像数量
-* 说明:
-* 1) 执行此函数后，TWAIN状态变为6
-* 2) 当count为0时, 可以关闭DS
-*/
-HGEXPORT HGResult HGAPI HGTwain_EndXfer(HGTwainDS ds, HGUInt* count);
-
-/* 停止所有传输
-* 参数:
-* 1) ds: in, DS句柄
-* 说明:
-* 1) 执行此函数后，TWAIN状态变为5
-* 2) 可以关闭DS
-*/
-HGEXPORT HGResult HGAPI HGTwain_Reset(HGTwainDS ds);
-
 #endif /* __HGTWAIN_H__ */
\ No newline at end of file
diff --git a/modules/twain_user/HGTwainImpl.cpp b/modules/twain_user/HGTwainImpl.cpp
index d57261ce..a00de4b1 100644
--- a/modules/twain_user/HGTwainImpl.cpp
+++ b/modules/twain_user/HGTwainImpl.cpp
@@ -8,22 +8,36 @@ HGTwainDSMImpl::HGTwainDSMImpl()
 {
 	m_hDll = NULL;
 	m_pDSMProc = NULL;
-	GetIdentity();
+	
+	m_AppId.Id = 0; // Initialize to 0 (Source Manager will assign real value)
+	m_AppId.Version.MajorNum = 3; //Your app's version number
+	m_AppId.Version.MinorNum = 8;
+	m_AppId.Version.Language = TWLG_USA;
+	m_AppId.Version.Country = TWCY_USA;
+	strcpy(m_AppId.Version.Info, "3.8");
+	m_AppId.ProtocolMajor = TWON_PROTOCOLMAJOR;
+	m_AppId.ProtocolMinor = TWON_PROTOCOLMINOR;
+	m_AppId.SupportedGroups = DG_IMAGE | DG_CONTROL;
+	strcpy(m_AppId.Manufacturer, "MICSS");
+	strcpy(m_AppId.ProductFamily, "Generic");
+	strcpy(m_AppId.ProductName, "MyTwain");
+
 	m_hWnd = NULL;
 	m_oldWndProc = NULL;
-	m_DSMOpen = HGFALSE;
 }
 
 HGTwainDSMImpl::~HGTwainDSMImpl()
 {
-	UnloadDSM();
+	
 }
 
-HGResult HGTwainDSMImpl::LoadDSM()
+HGResult HGTwainDSMImpl::Create(HWND hwnd)
 {
-	if (NULL != m_pDSMProc)
+	assert(NULL == m_oldWndProc);
+
+	if (NULL == hwnd)
 	{
-		return HGBASE_ERR_FAIL;
+		return HGBASE_ERR_INVALIDARG;
 	}
 
 	assert(NULL == m_hDll);
@@ -33,6 +47,7 @@ HGResult HGTwainDSMImpl::LoadDSM()
 		return HGBASE_ERR_FAIL;
 	}
 
+	assert(NULL == m_pDSMProc);
 	HGBase_GetDllProcAddress(m_hDll, MAKEINTRESOURCEA(1), (HGPointer*)&m_pDSMProc);
 	if (NULL == m_pDSMProc)
 	{
@@ -41,81 +56,30 @@ HGResult HGTwainDSMImpl::LoadDSM()
 		return HGBASE_ERR_FAIL;
 	}
 
-	return HGBASE_ERR_OK;
-}
-
-HGResult HGTwainDSMImpl::UnloadDSM()
-{
-	if (NULL == m_pDSMProc)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	// 先必须关闭DSM
-	CloseDSM();
-
-	m_pDSMProc = NULL;
-	HGBase_DestroyDll(m_hDll);
-	m_hDll = NULL;
-	return HGBASE_ERR_OK;
-}
-
-HGResult HGTwainDSMImpl::OpenDSM(HWND hwnd)
-{
-	if (NULL == m_pDSMProc || m_DSMOpen)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	if (NULL == hwnd)
-	{
-		return HGBASE_ERR_INVALIDARG;
-	}
-
 	USHORT ret = m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_PARENT, MSG_OPENDSM, (TW_MEMREF)&hwnd);
 	if (TWRC_SUCCESS != ret)
 	{
-		return HGBASE_ERR_FAIL;
+		m_pDSMProc = NULL;
+		HGBase_DestroyDll(m_hDll);
+		m_hDll = NULL;
+		return HGTWAIN_ERR_FAIL;
 	}
 
 	m_hWnd = hwnd;
 	m_mapWnd[m_hWnd] = this;
 	m_oldWndProc = (WNDPROC)SetWindowLongPtrW(m_hWnd, GWLP_WNDPROC, (LONG_PTR)NewWndProc);
-	m_DSMOpen = HGTRUE;
-
-	// 获取DS列表
-	TW_IDENTITY ds;
-	ret = m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETFIRST, &ds);
-	if (TWRC_SUCCESS == ret)
-	{
-		HGTwainDSImpl* dsImpl = new HGTwainDSImpl(this, &ds);
-		m_vpDSImpl.push_back(dsImpl);
-
-		while (TWRC_SUCCESS == m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETNEXT, &ds))
-		{
-			HGTwainDSImpl* dsImpl = new HGTwainDSImpl(this, &ds);
-			m_vpDSImpl.push_back(dsImpl);
-		}
-	}
-
 	return HGBASE_ERR_OK;
 }
 
-HGResult HGTwainDSMImpl::CloseDSM()
+HGResult HGTwainDSMImpl::Destroy()
 {
-	if (!m_DSMOpen)
+	assert(NULL != m_oldWndProc);
+
+	if (!m_listDSImpl.empty())
 	{
 		return HGBASE_ERR_FAIL;
 	}
 
-	// 先必须关闭DS
-	for (int i = 0; i < (int)m_vpDSImpl.size(); ++i)
-	{
-		m_vpDSImpl[i]->Close();
-		delete m_vpDSImpl[i];
-	}
-	m_vpDSImpl.clear();
-
 	m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_PARENT, MSG_CLOSEDSM, (TW_MEMREF)&m_hWnd);
 	SetWindowLongPtrW(m_hWnd, GWLP_WNDPROC, (LONG_PTR)m_oldWndProc);
 	m_oldWndProc = NULL;
@@ -129,117 +93,160 @@ HGResult HGTwainDSMImpl::CloseDSM()
 		}
 	}
 	m_hWnd = NULL;
-	m_DSMOpen = HGFALSE;
+
+	m_pDSMProc = NULL;
+	HGBase_DestroyDll(m_hDll);
+	m_hDll = NULL;
 	return HGBASE_ERR_OK;
 }
 
-HGResult HGTwainDSMImpl::GetDSList(class HGTwainDSImpl** dsImpl, HGUInt* size)
+HGResult HGTwainDSMImpl::GetDSCount(HGUInt* count)
 {
-	if (!m_DSMOpen)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	if (NULL == dsImpl || NULL == size || 0 == *size)
+	if (NULL == count)
 	{
 		return HGBASE_ERR_INVALIDARG;
 	}
 
-	HGUInt count = 0;
-	for (int i = 0; i < (int)m_vpDSImpl.size(); ++i)
+	HGUInt num = 0;
+	TW_IDENTITY ds;
+	if (TWRC_SUCCESS == m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETFIRST, &ds))
 	{
-		dsImpl[i] = m_vpDSImpl[i];
-		++count;
-
-		if (count >= *size)
+		++num;
+		while (TWRC_SUCCESS == m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETNEXT, &ds))
 		{
+			++num;
+		}
+	}
+
+	*count = num;
+	return HGBASE_ERR_OK;
+}
+
+HGResult HGTwainDSMImpl::GetDSName(HGUInt index, HGChar* name, HGUInt maxLen)
+{
+	if (NULL == name || 0 == maxLen)
+	{
+		return HGBASE_ERR_INVALIDARG;
+	}
+
+	std::vector<TW_IDENTITY> vds;
+	TW_IDENTITY ds;
+	if (TWRC_SUCCESS == m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETFIRST, &ds))
+	{
+		vds.push_back(ds);
+		while (TWRC_SUCCESS == m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETNEXT, &ds))
+		{
+			vds.push_back(ds);
+		}
+	}
+
+	if (index >= (HGUInt)vds.size())
+		return HGBASE_ERR_INVALIDARG;
+
+	if (maxLen < strlen(vds[index].ProductName) + 1)
+		return HGBASE_ERR_FAIL;
+	strcpy(name, vds[index].ProductName);
+	return HGBASE_ERR_OK;
+}
+
+HGResult HGTwainDSMImpl::OpenDS(HGUInt index, class HGTwainDSImpl** dsImpl)
+{
+	if (NULL == dsImpl)
+	{
+		return HGBASE_ERR_INVALIDARG;
+	}
+
+	std::vector<TW_IDENTITY> vds;
+	TW_IDENTITY ds;
+	if (TWRC_SUCCESS == m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETFIRST, &ds))
+	{
+		vds.push_back(ds);
+		while (TWRC_SUCCESS == m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETNEXT, &ds))
+		{
+			vds.push_back(ds);
+		}
+	}
+
+	if (index >= (HGUInt)vds.size())
+		return HGBASE_ERR_INVALIDARG;
+
+	class HGTwainDSImpl* newDSImpl = new HGTwainDSImpl(this);
+	HGResult ret = newDSImpl->Open(&vds[index]);
+	if (HGBASE_ERR_OK != ret)
+	{
+		delete newDSImpl;
+		return ret;
+	}
+
+	m_listDSImpl.push_back(newDSImpl);
+	*dsImpl = newDSImpl;
+	return HGBASE_ERR_OK;
+}
+
+HGResult HGTwainDSMImpl::OpenDefaultDS(class HGTwainDSImpl** dsImpl)
+{
+	if (NULL == dsImpl)
+	{
+		return HGBASE_ERR_INVALIDARG;
+	}
+
+	TW_IDENTITY defDS;
+	if (TWRC_SUCCESS != m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETDEFAULT, &defDS))
+	{
+		return HGTWAIN_ERR_FAIL;
+	}
+
+	class HGTwainDSImpl* newDSImpl = new HGTwainDSImpl(this);
+	HGResult ret = newDSImpl->Open(&defDS);
+	if (HGBASE_ERR_OK != ret)
+	{
+		delete newDSImpl;
+		return ret;
+	}
+
+	m_listDSImpl.push_back(newDSImpl);
+	*dsImpl = newDSImpl;
+	return HGBASE_ERR_OK;
+}
+
+HGResult HGTwainDSMImpl::OpenSelectedDS(class HGTwainDSImpl** dsImpl)
+{
+	if (NULL == dsImpl)
+	{
+		return HGBASE_ERR_INVALIDARG;
+	}
+
+	TW_IDENTITY selectDS;
+	if (TWRC_SUCCESS != m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_USERSELECT, &selectDS))
+	{
+		return HGTWAIN_ERR_FAIL;
+	}
+
+	class HGTwainDSImpl* newDSImpl = new HGTwainDSImpl(this);
+	HGResult ret = newDSImpl->Open(&selectDS);
+	if (HGBASE_ERR_OK != ret)
+	{
+		delete newDSImpl;
+		return ret;
+	}
+
+	m_listDSImpl.push_back(newDSImpl);
+	*dsImpl = newDSImpl;
+	return HGBASE_ERR_OK;
+}
+
+void HGTwainDSMImpl::RemoveDS(class HGTwainDSImpl* dsImpl)
+{
+	std::vector<class HGTwainDSImpl*>::iterator iter;
+	for (iter = m_listDSImpl.begin(); iter != m_listDSImpl.end(); ++iter)
+	{
+		if (*iter == dsImpl)
+		{
+			m_listDSImpl.erase(iter);
+			delete dsImpl;
 			break;
 		}
 	}
-
-	*size = count;
-	return HGBASE_ERR_OK;
-}
-
-HGResult HGTwainDSMImpl::GetDefaultDS(class HGTwainDSImpl** dsImpl)
-{
-	if (!m_DSMOpen)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	if (NULL == dsImpl)
-	{
-		return HGBASE_ERR_INVALIDARG;
-	}
-
-	assert(NULL != m_pDSMProc);
-	TW_IDENTITY defDS;
-	USHORT ret = m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETDEFAULT, &defDS);
-	if (TWRC_SUCCESS != ret)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	for (int i = 0; i < (int)m_vpDSImpl.size(); ++i)
-	{
-		if (0 == memcmp(&defDS, &m_vpDSImpl[i]->m_iden, sizeof(TW_IDENTITY)))
-		{
-			*dsImpl = m_vpDSImpl[i];
-			return HGBASE_ERR_OK;
-		}
-	}
-
-	return HGBASE_ERR_FAIL;
-}
-
-HGResult HGTwainDSMImpl::SelectDS(class HGTwainDSImpl** dsImpl)
-{
-	if (!m_DSMOpen)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	if (NULL == dsImpl)
-	{
-		return HGBASE_ERR_INVALIDARG;
-	}
-
-	assert(NULL != m_pDSMProc);
-	TW_IDENTITY selectDS;
-	USHORT ret = m_pDSMProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_USERSELECT, &selectDS);
-	if (TWRC_SUCCESS != ret)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	for (int i = 0; i < (int)m_vpDSImpl.size(); ++i)
-	{
-		if (0 == memcmp(&selectDS, &m_vpDSImpl[i]->m_iden, sizeof(TW_IDENTITY)))
-		{
-			*dsImpl = m_vpDSImpl[i];
-			return HGBASE_ERR_OK;
-		}
-	}
-
-	return HGBASE_ERR_FAIL;
-}
-
-void HGTwainDSMImpl::GetIdentity()
-{
-	m_AppId.Id = 0; // Initialize to 0 (Source Manager
-	// will assign real value)
-	m_AppId.Version.MajorNum = 3; //Your app's version number
-	m_AppId.Version.MinorNum = 8;
-	m_AppId.Version.Language = TWLG_USA;
-	m_AppId.Version.Country = TWCY_USA;
-	strcpy(m_AppId.Version.Info, "3.8");
-	m_AppId.ProtocolMajor = TWON_PROTOCOLMAJOR;
-	m_AppId.ProtocolMinor = TWON_PROTOCOLMINOR;
-	m_AppId.SupportedGroups = DG_IMAGE | DG_CONTROL;
-	strcpy(m_AppId.Manufacturer, "MICSS");
-	strcpy(m_AppId.ProductFamily, "Generic");
-	strcpy(m_AppId.ProductName, "MyTwain");
 }
 
 LRESULT CALLBACK HGTwainDSMImpl::NewWndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
@@ -253,36 +260,45 @@ LRESULT CALLBACK HGTwainDSMImpl::NewWndProc(HWND hWnd, UINT msg, WPARAM wParam,
 	msg2.wParam = wParam;
 	msg2.lParam = lParam;
 		
-	for (int i = 0; i < (int)p->m_vpDSImpl.size(); ++i)
+	for (int i = 0; i < (int)p->m_listDSImpl.size(); ++i)
 	{
-		if (p->m_vpDSImpl[i]->m_enable)
+		if (p->m_listDSImpl[i]->m_enable)
 		{
 			TW_EVENT twEvent;
 			twEvent.pEvent = (TW_MEMREF)&msg2;
 			twEvent.TWMessage = MSG_NULL;
-			USHORT ret = p->m_pDSMProc(&p->m_AppId, &p->m_vpDSImpl[i]->m_iden, DG_CONTROL, DAT_EVENT,
+			USHORT ret = p->m_pDSMProc(&p->m_AppId, &p->m_listDSImpl[i]->m_iden, DG_CONTROL, DAT_EVENT,
 				MSG_PROCESSEVENT, (TW_MEMREF)&twEvent);
 			if (TWRC_DSEVENT == ret)
 			{
-				HGUInt event = HGTWAIN_DSEVENT_UNKNOWN;
 				if (MSG_XFERREADY == twEvent.TWMessage)
 				{
-					HGBase_WriteInfo(HGBASE_INFOTYPE_DEBUG, "MSG_XFERREADY");
-					event = HGTWAIN_DSEVENT_XFERREADY;
+					while (1)
+					{
+						HGImage image = NULL;
+						p->m_listDSImpl[i]->ImageNativeXfer(0, 0, &image);
+						if (NULL != image)
+						{
+							if (NULL != p->m_listDSImpl[i]->m_imageFunc)
+								p->m_listDSImpl[i]->m_imageFunc((HGTwainDS)p->m_listDSImpl[i], image, p->m_listDSImpl[i]->m_imageParam);
+							HGBase_DestroyImage(image);
+						}						
+
+						HGUInt count = 0;
+						p->m_listDSImpl[i]->EndXfer(&count);
+						if (0 == count)
+						{
+							break;
+						}
+					}
+
+					p->m_listDSImpl[i]->Reset();
 				}
-				else if (MSG_CLOSEDSREQ == twEvent.TWMessage)
+				else if (MSG_CLOSEDSREQ == twEvent.TWMessage/* || MSG_CLOSEDSOK == twEvent.TWMessage*/)
 				{
-					HGBase_WriteInfo(HGBASE_INFOTYPE_DEBUG, "MSG_CLOSEDSREQ");
-					event = HGTWAIN_DSEVENT_CLOSEDSREQ;
+					if (NULL != p->m_listDSImpl[i]->m_eventFunc)
+						p->m_listDSImpl[i]->m_eventFunc((HGTwainDS)p->m_listDSImpl[i], HGBASE_ERR_OK, NULL, p->m_listDSImpl[i]->m_eventParam);
 				}
-				else if (MSG_CLOSEDSOK == twEvent.TWMessage)
-				{
-					HGBase_WriteInfo(HGBASE_INFOTYPE_DEBUG, "MSG_CLOSEDSOK");
-					event = HGTWAIN_DSEVENT_CLOSEDSOK;
-				}
-					
-				if (NULL != p->m_vpDSImpl[i]->m_eventFunc)
-					p->m_vpDSImpl[i]->m_eventFunc((HGTwainDS)p->m_vpDSImpl[i], event, p->m_vpDSImpl[i]->m_eventParam);
 			}
 		}
 	}
@@ -291,15 +307,17 @@ LRESULT CALLBACK HGTwainDSMImpl::NewWndProc(HWND hWnd, UINT msg, WPARAM wParam,
 }
 
 
-HGTwainDSImpl::HGTwainDSImpl(HGTwainDSMImpl* dsmImpl, const TW_IDENTITY* iden)
+HGTwainDSImpl::HGTwainDSImpl(HGTwainDSMImpl* dsmImpl)
 {
 	m_dsmImpl = dsmImpl;
-	memcpy(&m_iden, iden, sizeof(TW_IDENTITY));
+	memset(&m_iden, 0, sizeof(TW_IDENTITY));
 	m_open = HGFALSE;
 	m_showUI = HGFALSE;
 	m_parent = NULL;
 	m_eventFunc = NULL;
 	m_eventParam = NULL;
+	m_imageFunc = NULL;
+	m_imageParam = NULL;
 	m_enable = HGFALSE;
 }
 
@@ -308,136 +326,35 @@ HGTwainDSImpl::~HGTwainDSImpl()
 
 }
 
-HGResult HGTwainDSImpl::GetName(HGChar* name, HGUInt maxLen)
+HGResult HGTwainDSImpl::Open(const TW_IDENTITY* iden)
 {
-	strcpy_s(name, maxLen, m_iden.ProductName);
-	return HGBASE_ERR_OK;
-}
-
-HGResult HGTwainDSImpl::Open()
-{
-	if (m_open)
-	{
-		return HGBASE_ERR_FAIL;
-	}
+	assert(!m_open);
 
 	USHORT ret = m_dsmImpl->m_pDSMProc(&m_dsmImpl->m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_OPENDS, &m_iden);
 	if (TWRC_SUCCESS != ret)
 	{
-		return HGBASE_ERR_FAIL;
+		return HGTWAIN_ERR_FAIL;
 	}
 
+	memcpy(&m_iden, iden, sizeof(TW_IDENTITY));
 	m_open = HGTRUE;
 	return HGBASE_ERR_OK;
 }
 
 HGResult HGTwainDSImpl::Close()
 {
-	if (!m_open)
-	{
-		return HGBASE_ERR_FAIL;
-	}
+	assert(m_open);
 
 	Disable();
 	m_dsmImpl->m_pDSMProc(&m_dsmImpl->m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_CLOSEDS, (TW_MEMREF)&m_iden);
-
 	m_open = HGFALSE;
+	m_dsmImpl->RemoveDS(this);
 	return HGBASE_ERR_OK;
 }
 
-HGResult HGTwainDSImpl::SetCap(HGUInt cap, HGInt value)
+HGResult HGTwainDSImpl::EnableUIOnly(HGBool showUI, HWND parent, HGDSEventFunc eventFunc, HGPointer eventParam)
 {
-	if (!m_open)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	TW_UINT16 cap2 = 0;
-	if (HGTWAIN_DSCAP_DUPLEX == cap)
-		cap2 = CAP_DUPLEX;
-	else if (HGTWAIN_DSCAP_DUPLEXENABLED == cap)
-		cap2 = CAP_DUPLEXENABLED;
-	else if (HGTWAIN_DSCAP_XFERCOUNT == cap)
-		cap2 = CAP_XFERCOUNT;
-	if (0 == cap2)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	TW_CAPABILITY twCap;
-	twCap.Cap = (TW_UINT16)cap2;
-	twCap.ConType = TWON_ONEVALUE;
-	twCap.hContainer = GlobalAlloc(GHND, sizeof(TW_ONEVALUE));
-	if (NULL == twCap.hContainer)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	pTW_ONEVALUE pVal = (pTW_ONEVALUE)GlobalLock(twCap.hContainer);
-	assert(NULL != pVal);
-	pVal->ItemType = TWTY_INT32;
-	pVal->Item = (TW_UINT32)value;
-	GlobalUnlock(twCap.hContainer);
-
-	USHORT ret = m_dsmImpl->m_pDSMProc(&m_dsmImpl->m_AppId, &m_iden, DG_CONTROL, DAT_CAPABILITY, MSG_SET, &twCap);
-	if (TWRC_SUCCESS != ret)
-	{
-		GlobalFree(twCap.hContainer);
-		return HGBASE_ERR_FAIL;
-	}
-
-	GlobalFree(twCap.hContainer);
-	return HGBASE_ERR_OK;
-}
-
-HGResult HGTwainDSImpl::GetCap(HGUInt cap, HGInt* value)
-{
-	if (!m_open)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	if (NULL == value)
-	{
-		return HGBASE_ERR_INVALIDARG;
-	}
-
-	TW_UINT16 cap2 = 0;
-	if (HGTWAIN_DSCAP_DUPLEX == cap)
-		cap2 = CAP_DUPLEX;
-	else if (HGTWAIN_DSCAP_DUPLEXENABLED == cap)
-		cap2 = CAP_DUPLEXENABLED;
-	else if (HGTWAIN_DSCAP_XFERCOUNT == cap)
-		cap2 = CAP_XFERCOUNT;
-	if (0 == cap2)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	TW_CAPABILITY twCap;
-	twCap.Cap = (TW_UINT16)cap2;
-	twCap.ConType = TWON_ONEVALUE;
-	twCap.hContainer = NULL;
-
-	USHORT ret = m_dsmImpl->m_pDSMProc(&m_dsmImpl->m_AppId, &m_iden, DG_CONTROL, DAT_CAPABILITY, MSG_GETCURRENT, &twCap);
-	if (TWRC_SUCCESS != ret)
-	{
-		return HGBASE_ERR_FAIL;
-	}
-
-	assert(NULL != twCap.hContainer);
-	pTW_ONEVALUE pVal = (pTW_ONEVALUE)GlobalLock(twCap.hContainer);
-	assert(NULL != pVal);
-	*value = pVal->Item;
-	GlobalUnlock(twCap.hContainer);
-
-	GlobalFree(twCap.hContainer);
-	return HGBASE_ERR_OK;
-}
-
-HGResult HGTwainDSImpl::EnableUIOnly(HGBool showUI, HWND parent, HGDSEventFunc func, HGPointer param)
-{
-	if (!m_open || m_enable)
+	if (m_enable)
 	{
 		return HGBASE_ERR_FAIL;
 	}
@@ -448,20 +365,23 @@ HGResult HGTwainDSImpl::EnableUIOnly(HGBool showUI, HWND parent, HGDSEventFunc f
 	USHORT ret = m_dsmImpl->m_pDSMProc(&m_dsmImpl->m_AppId, &m_iden, DG_CONTROL, DAT_USERINTERFACE, MSG_ENABLEDSUIONLY, (TW_MEMREF)&twUI);
 	if (TWRC_SUCCESS != ret)
 	{
-		return HGBASE_ERR_FAIL;
+		return HGTWAIN_ERR_FAIL;
 	}
 
 	m_showUI = showUI;
 	m_parent = parent;
-	m_eventFunc = func;
-	m_eventParam = param;
+	m_eventFunc = eventFunc;
+	m_eventParam = eventParam;
+	m_imageFunc = NULL;
+	m_imageParam = NULL;
 	m_enable = HGTRUE;
 	return HGBASE_ERR_OK;
 }
 
-HGResult HGTwainDSImpl::Enable(HGBool showUI, HWND parent, HGDSEventFunc func, HGPointer param)
+HGResult HGTwainDSImpl::Enable(HGBool showUI, HWND parent, HGDSEventFunc eventFunc, HGPointer eventParam,
+	HGDSImageFunc imageFunc, HGPointer imageParam)
 {
-	if (!m_open || m_enable)
+	if (m_enable)
 	{
 		return HGBASE_ERR_FAIL;
 	}
@@ -472,13 +392,15 @@ HGResult HGTwainDSImpl::Enable(HGBool showUI, HWND parent, HGDSEventFunc func, H
 	USHORT ret = m_dsmImpl->m_pDSMProc(&m_dsmImpl->m_AppId, &m_iden, DG_CONTROL, DAT_USERINTERFACE, MSG_ENABLEDS, (TW_MEMREF)&twUI);
 	if (TWRC_SUCCESS != ret)
 	{
-		return HGBASE_ERR_FAIL;
+		return HGTWAIN_ERR_FAIL;
 	}
 
 	m_showUI = showUI;
 	m_parent = parent;
-	m_eventFunc = func;
-	m_eventParam = param;
+	m_eventFunc = eventFunc;
+	m_eventParam = eventParam;
+	m_imageFunc = imageFunc;
+	m_imageParam = imageParam;
 	m_enable = HGTRUE;
 	return HGBASE_ERR_OK;
 }
@@ -499,10 +421,68 @@ HGResult HGTwainDSImpl::Disable()
 	m_parent = NULL;
 	m_eventFunc = NULL;
 	m_eventParam = NULL;
+	m_imageFunc = NULL;
+	m_imageParam = NULL;
 	m_enable = HGFALSE;
 	return HGBASE_ERR_OK;
 }
 
+HGResult HGTwainDSImpl::SetCap(HGUInt cap, HGInt value)
+{
+	TW_CAPABILITY twCap;
+	twCap.Cap = (TW_UINT16)cap;
+	twCap.ConType = TWON_ONEVALUE;
+	twCap.hContainer = GlobalAlloc(GHND, sizeof(TW_ONEVALUE));
+	if (NULL == twCap.hContainer)
+	{
+		return HGBASE_ERR_FAIL;
+	}
+
+	pTW_ONEVALUE pVal = (pTW_ONEVALUE)GlobalLock(twCap.hContainer);
+	assert(NULL != pVal);
+	pVal->ItemType = TWTY_INT32;
+	pVal->Item = (TW_UINT32)value;
+	GlobalUnlock(twCap.hContainer);
+
+	USHORT ret = m_dsmImpl->m_pDSMProc(&m_dsmImpl->m_AppId, &m_iden, DG_CONTROL, DAT_CAPABILITY, MSG_SET, &twCap);
+	if (TWRC_SUCCESS != ret)
+	{
+		GlobalFree(twCap.hContainer);
+		return HGTWAIN_ERR_FAIL;
+	}
+
+	GlobalFree(twCap.hContainer);
+	return HGBASE_ERR_OK;
+}
+
+HGResult HGTwainDSImpl::GetCap(HGUInt cap, HGInt* value)
+{
+	if (NULL == value)
+	{
+		return HGBASE_ERR_INVALIDARG;
+	}
+
+	TW_CAPABILITY twCap;
+	twCap.Cap = (TW_UINT16)cap;
+	twCap.ConType = TWON_ONEVALUE;
+	twCap.hContainer = NULL;
+
+	USHORT ret = m_dsmImpl->m_pDSMProc(&m_dsmImpl->m_AppId, &m_iden, DG_CONTROL, DAT_CAPABILITY, MSG_GETCURRENT, &twCap);
+	if (TWRC_SUCCESS != ret)
+	{
+		return HGTWAIN_ERR_FAIL;
+	}
+
+	assert(NULL != twCap.hContainer);
+	pTW_ONEVALUE pVal = (pTW_ONEVALUE)GlobalLock(twCap.hContainer);
+	assert(NULL != pVal);
+	*value = pVal->Item;
+	GlobalUnlock(twCap.hContainer);
+
+	GlobalFree(twCap.hContainer);
+	return HGBASE_ERR_OK;
+}
+
 HGResult HGTwainDSImpl::ImageNativeXfer(HGUInt type, HGUInt origin, HGImage* image)
 {
 	if (!m_enable)
@@ -518,13 +498,13 @@ HGResult HGTwainDSImpl::ImageNativeXfer(HGUInt type, HGUInt origin, HGImage* ima
 	TW_IMAGEINFO info;
 	if (TWRC_SUCCESS != m_dsmImpl->m_pDSMProc(&m_dsmImpl->m_AppId, &m_iden, DG_IMAGE, DAT_IMAGEINFO, MSG_GET, (TW_MEMREF)&info))
 	{
-		return HGBASE_ERR_FAIL;
+		return HGTWAIN_ERR_FAIL;
 	}
 
 	HANDLE hMem = NULL;
 	if (TWRC_XFERDONE != m_dsmImpl->m_pDSMProc(&m_dsmImpl->m_AppId, &m_iden, DG_IMAGE, DAT_IMAGENATIVEXFER, MSG_GET, &hMem))
 	{
-		return HGBASE_ERR_FAIL;
+		return HGTWAIN_ERR_FAIL;
 	}
 
 	HGResult ret = HGBase_CreateImageFromDIB(hMem, NULL, type, origin, image);
@@ -548,7 +528,7 @@ HGResult HGTwainDSImpl::EndXfer(HGUInt* count)
 	USHORT ret = m_dsmImpl->m_pDSMProc(&m_dsmImpl->m_AppId, &m_iden, DG_CONTROL, DAT_PENDINGXFERS, MSG_ENDXFER, (TW_MEMREF)&twPend);
 	if (TWRC_SUCCESS != ret)
 	{
-		return HGBASE_ERR_FAIL;
+		return HGTWAIN_ERR_FAIL;
 	}
 
 	*count = twPend.Count;
@@ -566,7 +546,7 @@ HGResult HGTwainDSImpl::Reset()
 	USHORT ret = m_dsmImpl->m_pDSMProc(&m_dsmImpl->m_AppId, &m_iden, DG_CONTROL, DAT_PENDINGXFERS, MSG_RESET, (TW_MEMREF)&twPend);
 	if (TWRC_SUCCESS != ret)
 	{
-		return HGBASE_ERR_FAIL;
+		return HGTWAIN_ERR_FAIL;
 	}
 
 	return HGBASE_ERR_OK;
diff --git a/modules/twain_user/HGTwainImpl.hpp b/modules/twain_user/HGTwainImpl.hpp
index fcdab893..b59d4064 100644
--- a/modules/twain_user/HGTwainImpl.hpp
+++ b/modules/twain_user/HGTwainImpl.hpp
@@ -14,16 +14,16 @@ public:
 	HGTwainDSMImpl();
 	~HGTwainDSMImpl();
 
-	HGResult LoadDSM();
-	HGResult UnloadDSM();
-	HGResult OpenDSM(HWND hwnd);
-	HGResult CloseDSM();
-	HGResult GetDSList(class HGTwainDSImpl** dsImpl, HGUInt* size);
-	HGResult GetDefaultDS(class HGTwainDSImpl** dsImpl);
-	HGResult SelectDS(class HGTwainDSImpl** dsImpl);
+	HGResult Create(HWND hwnd);
+	HGResult Destroy();
+	HGResult GetDSCount(HGUInt* count);
+	HGResult GetDSName(HGUInt index, HGChar* name, HGUInt maxLen);
+	HGResult OpenDS(HGUInt index, class HGTwainDSImpl** dsImpl);
+	HGResult OpenDefaultDS(class HGTwainDSImpl** dsImpl);
+	HGResult OpenSelectedDS(class HGTwainDSImpl** dsImpl);
 
 private:
-	void GetIdentity();
+	void RemoveDS(class HGTwainDSImpl* dsImpl);
 	static LRESULT CALLBACK NewWndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);
 
 private:
@@ -33,26 +33,27 @@ private:
 	HWND m_hWnd;
 	static std::map<HWND, HGTwainDSMImpl*> m_mapWnd;
 	WNDPROC m_oldWndProc;
-	HGBool m_DSMOpen;
-	std::vector<class HGTwainDSImpl *> m_vpDSImpl;
+	std::vector<class HGTwainDSImpl *> m_listDSImpl;
 };
 
 class HGTwainDSImpl
 {
 	friend class HGTwainDSMImpl;
 public:
-	HGTwainDSImpl(HGTwainDSMImpl* dsmImpl, const TW_IDENTITY *iden);
+	HGTwainDSImpl(HGTwainDSMImpl* dsmImpl);
 	~HGTwainDSImpl();
 
 public:
-	HGResult GetName(HGChar* name, HGUInt maxLen);
-	HGResult Open();
+	HGResult Open(const TW_IDENTITY* iden);
 	HGResult Close();
+	HGResult EnableUIOnly(HGBool showUI, HWND parent, HGDSEventFunc eventFunc, HGPointer eventParam);
+	HGResult Enable(HGBool showUI, HWND parent, HGDSEventFunc eventFunc, HGPointer eventParam,
+		HGDSImageFunc imageFunc, HGPointer imageParam);
+	HGResult Disable();
+
+private:
 	HGResult SetCap(HGUInt cap, HGInt value);
 	HGResult GetCap(HGUInt cap, HGInt* value);
-	HGResult EnableUIOnly(HGBool showUI, HWND parent, HGDSEventFunc func, HGPointer param);
-	HGResult Enable(HGBool showUI, HWND parent, HGDSEventFunc func, HGPointer param);
-	HGResult Disable();
 	HGResult ImageNativeXfer(HGUInt type, HGUInt origin, HGImage* image);
 	HGResult EndXfer(HGUInt* count);
 	HGResult Reset();
@@ -65,6 +66,8 @@ private:
 	HWND m_parent;
 	HGDSEventFunc m_eventFunc;
 	HGPointer m_eventParam;
+	HGDSImageFunc m_imageFunc;
+	HGPointer m_imageParam;
 	HGBool m_enable;
 };