问题是这样的，现在目前github上使用twain调用扫描仪一直都是基于mfc工程，我是参考了这篇文章，并且把资源下载到本地，改造成控制台程序https://blog.csdn.net/a1101000099/article/details/38561365
然后，在构造回调函数的时候，我们之间出现了分歧，MFC是通过 CDialogEx::PreTranslateMessage(MSG* pMsg) 这个回调函数来处理twain回调的(这里的msg变量是mfc带的)
if(SourceEnabled())
{
TW_EVENT twEvent;
twEvent.pEvent = (TW_MEMREF)&msg;
twEvent.TWMessage = MSG_NULL;
CallTwainProc(&m_AppId,&m_Source,DG_CONTROL,DAT_EVENT,MSG_PROCESSEVENT,(TW_MEMREF)&twEvent);
if(GetRC() != TWRC_NOTDSEVENT)
{
TranslateMessage(twEvent);
}
return FALSE;
}
return FALSE;
但是我控制台程序，无法构造这个msg对象，于是我用了如下的方法,间隔2s，去获取一下twain的最新状态（听说可以直接注册twain回调函数，但是试过好几次，都失败了）
TW_EVENT twEvent;
MSG windowsMsg;
windowsMsg.message = WM_USER; // 模拟的消息类型
windowsMsg.wParam = 0; // 模拟的消息参数
windowsMsg.lParam = 0; // 模拟的消息参数
windowsMsg.hwnd = GetConsoleWindow(); // 控制台窗口句柄，获取当前控制台窗口的句柄
twEvent.pEvent = &windowsMsg;
twEvent.TWMessage = MSG_NULL;
while (true)
{
//间隔2s
std::this_thread::sleep_for(std::chrono::seconds(2));
CallTwainProc(&m_AppId, &m_Source, DG_CONTROL, DAT_EVENT, MSG_PROCESSEVENT, (TW_MEMREF)&twEvent);
TranslateMessage(twEvent);
}
重点来了，上面的CallTwainProc 返回的状态码一直是5，我查了下，这个状态码是失败的意思,也就是说，当前的问题是无法正常处理twain回调，也就无法从扫描仪拿到图片
附上我的TwainCpp.cpp完整代码
#define _CRT_SECURE_NO_WARNINGS
#include "twaincpp.h"
#include <cstddef>
#include "Base64Util.h"
#include "ImageUtil.h"
#include <chrono>
#include <thread>
/*
Constructor:
Parameters : HWND
Window to subclass
*/
CTwain::CTwain(HWND hWnd)
{
m_hTwainDLL = NULL;
m_pDSMProc = NULL;
m_bSourceSelected = FALSE;
m_bDSOpen = m_bDSMOpen = FALSE;
m_bSourceEnabled = FALSE;
m_bModalUI = TRUE;
m_nImageCount = TWCPP_ANYCOUNT;
if (hWnd)
{
InitTwain(hWnd);
}
}
CTwain::~CTwain()
{
ReleaseTwain();
}
/*
Initializes TWAIN interface . Is already called from the constructor.
It should be called again if ReleaseTwain is called.
hWnd is the window which has to subclassed in order to recieve
Twain messaged. Normally - this would be your main application window.
*/
BOOL CTwain::InitTwain(HWND hWnd)
{
char libName[512];
if (IsValidDriver())
{
return TRUE;
}
memset(&m_AppId, 0, sizeof(m_AppId));
if (!IsWindow(hWnd))
{
return FALSE;
}
m_hMessageWnd = hWnd;
strcpy(libName, "twain_32.dll");
m_hTwainDLL = LoadLibraryA(libName);
if (m_hTwainDLL != NULL)
{
if (!(m_pDSMProc = (DSMENTRYPROC)GetProcAddress(m_hTwainDLL, MAKEINTRESOURCEA(1))))
{
FreeLibrary(m_hTwainDLL);
m_hTwainDLL = NULL;
}
}
if (IsValidDriver())
{
GetIdentity();
m_bDSMOpen = CallTwainProc(&m_AppId, NULL, DG_CONTROL, DAT_PARENT, MSG_OPENDSM, (TW_MEMREF)&m_hMessageWnd);
return TRUE;
}
else
{
return FALSE;
}
}
/*
Releases the twain interface . Need not be called unless you
want to specifically shut it down.
*/
void CTwain::ReleaseTwain()
{
if (IsValidDriver())
{
CloseDSM();
FreeLibrary(m_hTwainDLL);
m_hTwainDLL = NULL;
m_pDSMProc = NULL;
}
}
/*
Returns true if a valid driver has been loaded
*/
BOOL CTwain::IsValidDriver() const
{
return (m_hTwainDLL && m_pDSMProc);
}
/*
Entry point into Twain. For a complete description of this
routine please refer to the Twain specification 1.8
*/
BOOL CTwain::CallTwainProc(pTW_IDENTITY pOrigin, pTW_IDENTITY pDest,
TW_UINT32 DG, TW_UINT16 DAT, TW_UINT16 MSG,
TW_MEMREF pData)
{
if (IsValidDriver())
{
USHORT ret_val;
ret_val = (*m_pDSMProc)(pOrigin, pDest, DG, DAT, MSG, pData);
m_returnCode = ret_val;
if (ret_val != TWRC_SUCCESS)
{
(*m_pDSMProc)(pOrigin, pDest, DG_CONTROL, DAT_STATUS, MSG_GET, &m_Status);
}
return (ret_val == TWRC_SUCCESS);
}
else
{
m_returnCode = TWRC_FAILURE;
return FALSE;
}
}
/*
This function should ideally be overridden in the derived class . If only a
few fields need to be updated , call CTawin::GetIdentity first in your
derived class
*/
void CTwain::GetIdentity()
{
// Expects all the fields in m_AppId to be set except for the id field.
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");
}
/*
Called to display a dialog box to select the Twain source to use.
This can be overridden if a list of all sources is available
to the application. These sources can be enumerated by Twain.
it is not yet supportted by CTwain.
*/
BOOL CTwain::SelectSource()
{
memset(&m_Source, 0, sizeof(m_Source));
if (!SourceSelected())
{
SelectDefaultSource();
}
if (CallTwainProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_USERSELECT, &m_Source))
{
m_bSourceSelected = TRUE;
}
return m_bSourceSelected;
}
/*
Called to select the default source
*/
BOOL CTwain::SelectDefaultSource()
{
m_bSourceSelected = CallTwainProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETDEFAULT, &m_Source);
return m_bSourceSelected;
}
/*
Closes the Data Source
*/
void CTwain::CloseDS()
{
if (DSOpen())
{
DisableSource();
CallTwainProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_CLOSEDS, (TW_MEMREF)&m_Source);
m_bDSOpen = FALSE;
}
}
/*
Closes the Data Source Manager
*/
void CTwain::CloseDSM()
{
if (DSMOpen())
{
CloseDS();
CallTwainProc(&m_AppId, NULL, DG_CONTROL, DAT_PARENT, MSG_CLOSEDSM, (TW_MEMREF)&m_hMessageWnd);
m_bDSMOpen = FALSE;
}
}
/*
Returns true if the Data Source Manager is Open
*/
BOOL CTwain::DSMOpen() const
{
return IsValidDriver() && m_bDSMOpen;
}
/*
Returns true if the Data Source is Open
*/
BOOL CTwain::DSOpen() const
{
return IsValidDriver() && DSMOpen() && m_bDSOpen;
}
/*
Opens a Data Source supplied as the input parameter
*/
BOOL CTwain::OpenSource(TW_IDENTITY* pSource)
{
if (pSource)
{
m_Source = *pSource;
}
if (DSMOpen())
{
m_bDSOpen = CallTwainProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_OPENDS, (TW_MEMREF)&m_Source);
}
return DSOpen();
}
/*
Should be called from the main message loop of the application. Can always be called,
it will not process the message unless a scan is in progress.
*/
BOOL CTwain::ProcessMessage(MSG msg)
{
if (SourceEnabled())
{
TW_EVENT twEvent;
twEvent.pEvent = (TW_MEMREF)&msg;
twEvent.TWMessage = MSG_NULL;
CallTwainProc(&m_AppId, &m_Source, DG_CONTROL, DAT_EVENT, MSG_PROCESSEVENT, (TW_MEMREF)&twEvent);
if (GetRC() != TWRC_NOTDSEVENT)
{
TranslateMessage(twEvent);
}
return FALSE;
}
return FALSE;
}
/*
Queries the capability of the Twain Data Source
*/
BOOL CTwain::GetCapability(TW_CAPABILITY& twCap, TW_UINT16 cap, TW_UINT16 conType)
{
if (DSOpen())
{
twCap.Cap = cap;
twCap.ConType = conType;
twCap.hContainer = NULL;
if (CallTwainProc(&m_AppId, &m_Source, DG_CONTROL, DAT_CAPABILITY, MSG_GET, (TW_MEMREF)&twCap))
{
return TRUE;
}
}
return FALSE;
}
/*
Queries the capability of the Twain Data Source
*/
BOOL CTwain::GetCapability(TW_UINT16 cap, TW_UINT32& value)
{
TW_CAPABILITY twCap;
if (GetCapability(twCap, cap))
{
pTW_ONEVALUE pVal;
pVal = (pTW_ONEVALUE)GlobalLock(twCap.hContainer);
if (pVal)
{
value = pVal->Item;
GlobalUnlock(pVal);
GlobalFree(twCap.hContainer);
return TRUE;
}
}
return FALSE;
}
/*
Sets the capability of the Twain Data Source
*/
BOOL CTwain::SetCapability(TW_UINT16 cap, TW_UINT16 value, BOOL sign)
{
if (DSOpen())
{
TW_CAPABILITY twCap;
pTW_ONEVALUE pVal;
BOOL ret_value = FALSE;
twCap.Cap = cap;
twCap.ConType = TWON_ONEVALUE;
twCap.hContainer = GlobalAlloc(GHND, sizeof(TW_ONEVALUE));
if (twCap.hContainer)
{
pVal = (pTW_ONEVALUE)GlobalLock(twCap.hContainer);
pVal->ItemType = sign ? TWTY_INT16 : TWTY_UINT16;
pVal->Item = (TW_UINT32)value;
GlobalUnlock(twCap.hContainer);
ret_value = SetCapability(twCap);
GlobalFree(twCap.hContainer);
}
return ret_value;
}
return FALSE;
}
BOOL CTwain::SetResolution(TW_UINT16 cap, TW_UINT32 value)
{
if (DSOpen())
{
TW_CAPABILITY twCap;
pTW_ONEVALUE pVal;
BOOL ret_value = FALSE;
twCap.Cap = cap;
twCap.ConType = TWON_ONEVALUE;
twCap.hContainer = GlobalAlloc(GHND, sizeof(TW_ONEVALUE));
if (twCap.hContainer)
{
pVal = (pTW_ONEVALUE)GlobalLock(twCap.hContainer);
pVal->ItemType = TWTY_FIX32;
pVal->Item = (TW_UINT32)value;
GlobalUnlock(twCap.hContainer);
ret_value = SetCapability(twCap);
GlobalFree(twCap.hContainer);
}
return ret_value;
}
return FALSE;
}
/*
Sets the capability of the Twain Data Source
*/
BOOL CTwain::SetCapability(TW_CAPABILITY& cap)
{
if (DSOpen())
{
return CallTwainProc(&m_AppId, &m_Source, DG_CONTROL, DAT_CAPABILITY, MSG_SET, (TW_MEMREF)&cap);
}
return FALSE;
}
/*
Sets the number of images which can be accpeted by the application at one time
*/
BOOL CTwain::SetImageCount(TW_INT16 nCount)
{
if (SetCapability(CAP_XFERCOUNT, (TW_UINT16)nCount, TRUE))
{
m_nImageCount = nCount;
return TRUE;
}
else
{
if (GetRC() == TWRC_CHECKSTATUS)
{
TW_UINT32 count;
if (GetCapability(CAP_XFERCOUNT, count))
{
nCount = (TW_INT16)count;
if (SetCapability(CAP_XFERCOUNT, nCount))
{
m_nImageCount = nCount;
return TRUE;
}
}
}
}
return FALSE;
}
/*
Called to enable the Twain Acquire Dialog. This too can be
overridden but is a helluva job .
*/
BOOL CTwain::EnableSource(BOOL showUI)
{
if (DSOpen() && !SourceEnabled())
{
twUI.ShowUI = FALSE;
twUI.hParent = (TW_HANDLE)m_hMessageWnd;
if (CallTwainProc(&m_AppId, &m_Source, DG_CONTROL, DAT_USERINTERFACE, MSG_ENABLEDS, (TW_MEMREF)&twUI))
{
m_bSourceEnabled = TRUE;
m_bModalUI = twUI.ModalUI;
}
else
{
m_bSourceEnabled = FALSE;
m_bModalUI = TRUE;
}
return m_bSourceEnabled;
}
return FALSE;
}
/*
Called to acquire images from the source. parameter numImages i the
numberof images that you an handle concurrently
*/
BOOL CTwain::Acquire(int numImages, TW_UINT16 duplex, TW_UINT16 size, TW_UINT16 pixel, TW_UINT16 resolution)
{
if (DSOpen() || OpenSource())
{
BOOL ret_value = SetCapability(CAP_DUPLEXENABLED, duplex, TRUE);
ret_value = SetCapability(ICAP_SUPPORTEDSIZES, size, TRUE);
ret_value = SetCapability(ICAP_PIXELTYPE, pixel, TRUE);
ret_value = SetResolution(ICAP_XRESOLUTION, resolution);
ret_value = SetResolution(ICAP_YRESOLUTION, resolution);
//设置为jpeg格式返回，默认的位图文件很大
SetCapability(ICAP_IMAGEFILEFORMAT, TWCP_JPEG);
if (SetImageCount(numImages))
{
if (EnableSource())
{
return TRUE;
}
}
}
return FALSE;
}
/*
Called to disable the source.
*/
BOOL CTwain::DisableSource()
{
if (SourceEnabled())
{
if (CallTwainProc(&m_AppId, &m_Source, DG_CONTROL, DAT_USERINTERFACE, MSG_DISABLEDS, &twUI))
{
m_bSourceEnabled = FALSE;
return TRUE;
}
}
return FALSE;
}
/*
Called by ProcessMessage to Translate a TWAIN message
*/
void CTwain::TranslateMessage(TW_EVENT& twEvent)
{
switch (twEvent.TWMessage)
{
case MSG_XFERREADY:
TransferImage();
break;
case MSG_CLOSEDSREQ:
if (CanClose())
{
CloseDS();
}
break;
}
}
/*
Gets Imageinfo for an image which is about to be transferred.
*/
BOOL CTwain::GetImageInfo(TW_IMAGEINFO& info)
{
if (SourceEnabled())
{
return CallTwainProc(&m_AppId, &m_Source, DG_IMAGE, DAT_IMAGEINFO, MSG_GET, (TW_MEMREF)&info);
}
return FALSE;
}
/*
Trasnfers the image or cancels the transfer depending on the state of the
TWAIN system
*/
void CTwain::TransferImage()
{
TW_IMAGEINFO info;
BOOL bContinue = TRUE;
while (bContinue)
{
if (GetImageInfo(info))
{
int permission;
permission = ShouldTransfer(info);
switch (permission)
{
case TWCPP_CANCELTHIS:
bContinue = EndTransfer();
break;
case TWCPP_CANCELALL:
CancelTransfer();
bContinue = FALSE;
break;
case TWCPP_DOTRANSFER:
bContinue = GetImage(info);
break;
}
}
}
}
/*
Ends the current transfer.
Returns TRUE if the more images are pending
*/
BOOL CTwain::EndTransfer()
{
TW_PENDINGXFERS twPend;
if (CallTwainProc(&m_AppId, &m_Source, DG_CONTROL, DAT_PENDINGXFERS, MSG_ENDXFER, (TW_MEMREF)&twPend))
{
if (twPend.Count == 0)
{
DisableSource();
}
return twPend.Count != 0;
}
return FALSE;
}
/*
Aborts all transfers
*/
void CTwain::CancelTransfer()
{
TW_PENDINGXFERS twPend;
CallTwainProc(&m_AppId, &m_Source, DG_CONTROL, DAT_PENDINGXFERS, MSG_RESET, (TW_MEMREF)&twPend);
}
/*
Calls TWAIN to actually get the image
*/
BOOL CTwain::GetImage(TW_IMAGEINFO& info)
{
HANDLE hBitmap;
CallTwainProc(&m_AppId, &m_Source, DG_IMAGE, DAT_IMAGENATIVEXFER, MSG_GET, &hBitmap);
switch (m_returnCode)
{
case TWRC_XFERDONE:
CopyImage(hBitmap, info);
break;
case TWRC_CANCEL:
break;
case TWRC_FAILURE:
CancelTransfer();
return FALSE;
}
GlobalFree(hBitmap);
return EndTransfer();
}
/**
* 获取驱动列表
*/
vector<TW_IDENTITY> CTwain::getSources()
{
sourceList.clear();
if (CallTwainProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETFIRST, &m_Source)) {
while (CallTwainProc(&m_AppId, NULL, DG_CONTROL, DAT_IDENTITY, MSG_GETNEXT, &m_Source)) {
TW_IDENTITY temp_Source = m_Source;
sourceList.push_back(temp_Source);
}
}
return sourceList;
}
void CTwain::CopyImage(HANDLE hBitmap, TW_IMAGEINFO& info) {
storeImage(hBitmap, info);
}
TW_IDENTITY CTwain::getSourceByName(const char* sourceName) {
for (size_t i = 0; i < sourceList.size(); i++) {
// 使用迭代器访问向量元素
string name = sourceList[i].ProductName;
if (sourceName == name) {
return sourceList[i];
}
}
return TW_IDENTITY{};
}
void CALLBACK ScanCallbackFunction(pTW_IDENTITY pOrigin, pTW_IDENTITY pDest, TW_UINT32 uiMsg, TW_MEMREF pData)
{
int a = 0;
}
void CTwain::startScan(const char* sourceName) {
TW_IDENTITY source = getSourceByName(sourceName);
if (source.Id == 0 && source.Version.MajorNum == 0 && source.Version.MinorNum == 0) {
return;
}
if (OpenSource(&source))
{
BOOL ret_value = SetCapability(CAP_DUPLEXENABLED, 0, TRUE);
ret_value = SetCapability(ICAP_SUPPORTEDSIZES, 0, TRUE);
ret_value = SetCapability(ICAP_PIXELTYPE, 0, TRUE);
ret_value = SetResolution(ICAP_XRESOLUTION, 0);
ret_value = SetResolution(ICAP_YRESOLUTION, 300);
//SetImageCount(-1)
EnableSource(true);
//注册回调事件
if (SourceEnabled())
{
TW_EVENT twEvent;
MSG windowsMsg;
windowsMsg.message = WM_USER; // 模拟的消息类型
windowsMsg.wParam = 0; // 模拟的消息参数
windowsMsg.lParam = 0; // 模拟的消息参数
windowsMsg.hwnd = GetConsoleWindow(); // 控制台窗口句柄，获取当前控制台窗口的句柄
twEvent.pEvent = &windowsMsg;
twEvent.TWMessage = MSG_NULL;
while (true)
{
//间隔2s
std::this_thread::sleep_for(std::chrono::seconds(2));
CallTwainProc(&m_AppId, &m_Source, DG_CONTROL, DAT_EVENT, MSG_PROCESSEVENT, (TW_MEMREF)&twEvent);
TranslateMessage(twEvent);
}
}
}
}
请确认你的消息构建：
MSG windowsMsg;
windowsMsg.message = WM_USER; // 模拟的消息类型
windowsMsg.wParam = 0; // 模拟的消息参数
windowsMsg.lParam = 0; // 模拟的消息参数
windowsMsg.hwnd = GetConsoleWindow(); // 控制台窗口句柄，获取当前控制台窗口的句柄
twEvent.pEvent = &windowsMsg;
twEvent.TWMessage = MSG_NULL;
和消息循环中的一致。，我感觉这里您构建的有点问题。
如果这个库依赖Win32的窗口和消息循环，那么应该在main函数最后运行消息循环，
控制台程序也是可以创建窗口和进行消息循环的，
创建一个窗口CreateWindow，但不要显示它ShowWindow，
main函数最后进行消息循环:
MSG msg;
while(GetMessage(&msg, NULL, 0, 0)){
//在这里取得的消息传递给twain这个库
TranslateMessage(&msg);
DispatchMessage(&msg);
}
我大概扫了一下你的代码
提供的代码，可能存在一下几个方面吧
MSG 对象的构造：在 MFC 应用程序中，MSG 对象是由 Windows 消息循环系统自动创建和传递的。而在控制台程序中，没有消息循环，也没有自动创建的 MSG 对象。因此，您需要手动创建 MSG 对象，并将其传递给 TWAIN 接口。在您的代码中，您创建了一个模拟的 MSG 对象，但是可能没有正确设置其各个成员变量。您可以参考 Windows API 中的 GetMessage() 函数的文档，了解如何正确创建和设置 MSG 对象。
TWAIN 回调函数的注册：在 MFC 应用程序中，TWAIN 回调函数通常是通过 TWAIN 接口提供的 TW_CALLBACK 类型来注册的。而在控制台程序中，您需要手动注册 TWAIN 回调函数，以便能够接收 TWAIN 接口的消息和事件。您可以参考 TWAIN 接口的文档，了解如何注册 TWAIN 回调函数。
TWAIN 应用程序 ID 和数据源 ID 的获取：在您的代码中，您使用了 m_AppId 和 m_Source 变量来表示 TWAIN 应用程序 ID 和数据源 ID。这些变量应该是在 TWAIN 接口初始化时获取的。您可以检查一下您的代码，确保在调用 CallTwainProc() 函数之前已经正确获取了 TWAIN 应用程序 ID 和数据源 ID。
TWAIN 接口的返回值和错误码：在您的代码中，您调用了 CallTwainProc() 函数来调用 TWAIN 接口。该函数返回一个 TW_UINT16 类型的值，表示 TWAIN 接口的返回值和错误码。您可以检查一下该返回值，并根据 TWAIN 接口的文档来判断是否出现了错误。您可以使用 TWAIN 接口提供的 TWCC 宏来检查错误码。
答案由GPT-4Plus大模型(语音)与博主@晓码自在合作编写：
根据您的描述,目前在控制台程序中调用TWAIN接口获取扫描仪图片时遇到的主要问题是:
要解决这个问题,有以下几点建议:
不必构造MFC的消息对象MSG,直接使用Windows消息即可。您当前代码中构造的windowsMsg对象是正确的。
需要在调用CallTwainProc后正确处理TW_EVENT中的消息,这对应TranslateMessage的处理。如果无法正确处理消息,状态码会返回失败。
不需要每2秒查询一次状态,可以直接注册TWAIN回调函数,在图片采集等状态变更时会自动触发回调。
TWAIN回调函数需要定义为全局函数,格式为:
TW_CALLBACK CallbackFunc(pTW_IDENTITY pOrigin, TW_UINT32 DG, TW_UINT16 DAT, TW_UINT16 MSG, TW_MEMREF pData);
TwainRegisterCallback(m_Source, CallbackFunc, pAppID);
综上,您应当:
构造windowsMsg作为TW_EVENT中的消息对象,而不必构造MSG对象
确保TranslateMessage正确处理TW_EVENT中的消息
注册TWAIN回调函数CallbackFunc,而不必每2秒查询状态
回调函数格式定义为TW_CALLBACK,需要在SourceEnable后调用TwainRegisterCallback进行注册
具体代码可修改为:
cpp
TW_CALLBACK CallbackFunc(pTW_IDENTITY pOrigin, TW_UINT32 DG, TW_UINT16 DAT, TW_UINT16 MSG, TW_MEMREF pData)
{
// 处理TWAIN回调消息,获取图像等
}
// 开启源并注册回调
SourceEnable();
TwainRegisterCallback(m_Source, CallbackFunc, pAppID);
// 主循环
while (true)
{
}
希望上述分析与建议能够帮助您解决问题,成功调用TWAIN接口获取扫描仪图像。
VC中基于TWAIN协议控制扫描仪
可以借鉴下
https://blog.csdn.net/sinat_29048381/article/details/80733727