Qt4 and TWAIN scanning

[jokinb]

Perdona Nyaw, pero al bajarme los dos ficheros qtwain.zip y QtTwainScan.zip e intentarlos abrir se produce un error: "Final inesperado del archivo".
Como estoy interesado en poder añadir capacidades para escanear a una aplicación que estoy haciendo, podrÃ*as facilitarnos esos archivos correctamente.

¿Has hecho algún progreso al respecto?

Muchas gracias.

[^NyAw^]

Hi,

Dear jokinb,
Don't post spanish posts on this forum as people can't read it.
I just downloaded the file and uncopressed using WinRAR and it had no error.
Respect to the progress on this, I said that it works not very well but it is perfect fot my application.
Maybe the newest 2 version of TWAIN will be better.
Of course you can send me private messages written in spanish.

[jokinb]

I will write in English.
I have domnloaded the qtwain.zip file and I have got the same error. "Unexpected end of archive".

It is posible to use the WIA tecnology in Qt?
Thanks
Jokinb

[^NyAw^]

Hi,

Try this, I only donwloaded the file from this forum uncompressed and compressed again.

[jokinb]

Finally , with a lot of tricks I have got the qtwain file downloaded.
How many files are in. I get six. It is ok.?

Thanks
Jokinb

[^NyAw^]

Hi,

Yes, there are 6 files.

I don't understand why you have to use a lot of tricks. Is there any other person that can try downloading the file and decompress it to check if there is any error on uncompress it?

[nish]

the notice on the forum says that they have some problems into attachments before 1st sep 2010. may be that is the issue. the new file is good.

[jokinb]

I don´t Know but the newest file had the same problem that the first one to open. I don´t Know why but... I tried with diferents programs to deskompress the file . The same message..."end of file corrupt"... "the file can´t bee opened"....

Finnally i got the file opened in an unusual way. I have the six files and must find time to study them.

Thanks

Jokinb

[Kata]

Hello all,

Have you got any simple example to use this class ?
I have try to acquire and save 1 A4 image :

#include <iostream>
#include "qtwain.h"
 
using namespace std;
 
int main(int agc, char **argv)
{
        QTwain t;
        t.initTwain();
        if(t.isValidDriver() && t.selectSource())
        {
                t.setResolutionY(1654);
                t.setResolutionX(2339);
                t.setDepth(1);
                t.acquire(1);
        }
    return 0;
}

#include <iostream>
#include "qtwain.h"

using namespace std;

int main(int agc, char **argv)
{
        QTwain t;
        t.initTwain();
        if(t.isValidDriver() && t.selectSource())
        {
                t.setResolutionY(1654);
                t.setResolutionX(2339);
                t.setDepth(1);
                t.acquire(1);
        }
    return 0;
}

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But it doesn't work; why ?

For your help, by advance, thanks.

[high_flyer]

The 'example' in the code!
Just look in there.

void QtTwainScan::scan()
{
	if (!m_pTwain->initTwain())
		qWarning("initTwain() call not successful!");
	else
		if (!m_pTwain->selectSource())
			qWarning("selectSource() call not successful!");
		else
			if (!m_pTwain->acquire())
				qWarning("acquire() call not successful!");
}

void QtTwainScan::scan()
{
	if (!m_pTwain->initTwain())
		qWarning("initTwain() call not successful!");
	else
		if (!m_pTwain->selectSource())
			qWarning("selectSource() call not successful!");
		else
			if (!m_pTwain->acquire())
				qWarning("acquire() call not successful!");
}

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[Kata]

The 'example' in the code!
Just look in there.

void QtTwainScan::scan()
{
	if (!m_pTwain->initTwain())
		qWarning("initTwain() call not successful!");
	else
		if (!m_pTwain->selectSource())
			qWarning("selectSource() call not successful!");
		else
			if (!m_pTwain->acquire())
				qWarning("acquire() call not successful!");
}

void QtTwainScan::scan()
{
	if (!m_pTwain->initTwain())
		qWarning("initTwain() call not successful!");
	else
		if (!m_pTwain->selectSource())
			qWarning("selectSource() call not successful!");
		else
			if (!m_pTwain->acquire())
				qWarning("acquire() call not successful!");
}

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Happy new year.
I have tried this (with QtCreator or the CLI) :

#include <QApplication>
#include "qtwain.h"
 
int main(int argc, char **argv)
{
    QApplication app(argc, argv);
    QTwain m_pTwain;
    if (!m_pTwain.initTwain())
        qWarning("initTwain() call not successful!");
    else
        if (!m_pTwain.selectSource())
            qWarning("selectSource() call not successful!");
        else
            if (!m_pTwain.acquire())
                qWarning("acquire() call not successful!");
    return app.exec();
}

#include <QApplication>
#include "qtwain.h"

int main(int argc, char **argv)
{
    QApplication app(argc, argv);
    QTwain m_pTwain;
    if (!m_pTwain.initTwain())
        qWarning("initTwain() call not successful!");
    else
        if (!m_pTwain.selectSource())
            qWarning("selectSource() call not successful!");
        else
            if (!m_pTwain.acquire())
                qWarning("acquire() call not successful!");
    return app.exec();
}

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But I still have a segmentation error,
Have you ever have this bug ?

By advance,
Thanks

[high_flyer]

Happy new year to you too!

I just had a 2 seconds look - to see if I could help you getting started.
I didn't look further.
But you should.
Maybe there are some initializations needed to be done, I don't know, stuff like that.
Follow the application in the debugger, and see exactly where it crashes, it will tell you a lot about what the problem is.

[d_stranz]

It is probably because the QTwain class requires an event loop to be running, and until you call app.exec(), there is no event loop.

Your code is fundamentally different from the example in the previous post in the thread. You need to move your twain code into a method that gets called after the event loop has started.

[srsr]

I will write in English.
I have domnloaded the qtwain.zip file and I have got the same error. "Unexpected end of archive".

It is posible to use the WIA tecnology in Qt?
Thanks
Jokinb

and

YES it is possible to use WIA technology with Qt. It's even necessary with Windows10.
Just start with Windows SDK sample code :for example fiScanner

SRSR