[Reference: http://www.yolinux.com/TUTORIALS/LinuxTutorialC++StringClass.html]

#include <stdio.h>
#include <string.h>
#include <iostream>
#include <sstream>
#include <string>
using namespace std;
int main ()
{
string a(“merging”);
string b(” successful\n”);
cout<<a+b;
ostringstream oss;
oss<<1000;
cout<<a+b+oss.str();
return 0;
}
This technique is used to extract images from vec files in openCV, which is included in my other blog.

I edited the file <opencvfolder>/apps/haartraining/src/cvsamples.cpp

first, include the following headers

#include <stdio.h>
#include <iostream>
#include <sstream>
#include <string>

function edited is cvShowVecSamples, in the for-loop for showing the images, edit as following

std::ostringstream stm;       //added
icvGetHaarTraininDataFromVecCallback( sample, &file );
stm<<”/temp/vecextracted/”;       //added folder in which to extract images
stm << i;            //added filename which will be given to save image, integer to string conversion
stm << “.pgm”; //added
std::cout<<”\n”; //added
std::cout<<stm.str(); //added
const char *filename = stm.str().c_str(); //added
std::cout<<filename; //added
cvSaveImage(filename, sample); //added
if( scale != 1.0 ) cvResize( sample, scaled_sample, CV_INTER_LINEAR);
cvShowImage(“Sample”, scaled_sample );
cvWaitKey(50);

//added == these are the lines that i have added, other lines are the default of OpenCV

Now, you have to rebuild the files. So, in the command line type

make all

Now, when you execute opencv-createsample -vec vecfile.vec, the images are extracted too.

ttyS0<*1>: ATQ0 V1 E1 — failed with 2400 baud, next try: 9600 baud
ttyS0<*1>: ATQ0 V1 E1 — failed with 9600 baud, next try: 115200 baud
ttyS0<*1>: ATQ0 V1 E1 — and failed too at 115200, giving up.
ttyS1<*1>: ATQ0 V1 E1 — failed with 2400 baud, next try: 9600 baud
ttyS1<*1>: ATQ0 V1 E1 — failed with 9600 baud, next try: 115200 baud
ttyS1<*1>: ATQ0 V1 E1 — and failed too at 115200, giving up.
ttyS2<*1>: ATQ0 V1 E1 — failed with 2400 baud, next try: 9600 baud
ttyS2<*1>: ATQ0 V1 E1 — failed with 9600 baud, next try: 115200 baud
ttyS2<*1>: ATQ0 V1 E1 — and failed too at 115200, giving up.
ttyS3<*1>: ATQ0 V1 E1 — failed with 2400 baud, next try: 9600 baud
ttyS3<*1>: ATQ0 V1 E1 — failed with 9600 baud, next try: 115200 baud
ttyS3<*1>: ATQ0 V1 E1 — and failed too at 115200, giving up.
WvModem<*1>: Cannot get information for serial port.
ttyUSB0<*1>: ATQ0 V1 E1 — failed with 2400 baud, next try: 9600 baud
ttyUSB0<*1>: ATQ0 V1 E1 — failed with 9600 baud, next try: 115200 baud
ttyUSB0<*1>: ATQ0 V1 E1 — OK
ttyUSB0<*1>: ATQ0 V1 E1 Z — OK
ttyUSB0<*1>: ATQ0 V1 E1 S0=0 — OK
ttyUSB0<*1>: ATQ0 V1 E1 S0=0 &C1 — OK
ttyUSB0<*1>: ATQ0 V1 E1 S0=0 &C1 &D2 — OK
ttyUSB0<*1>: ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0 — OK
ttyUSB0<*1>: Modem Identifier: ATI — ERROR
ttyUSB0<*1>: Speed 230400: AT — Speed 230400: AT — Speed 230400: AT — Max speed is 115200; that should be safe.
ttyUSB0<*1>: ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0 — and failed too at 115200, giving up.

Sorry, no modem was detected! Is it in use by another program?
Did you configure it properly with setserial?

Please read the FAQ at http://open.nit.ca/wvdial/

If you still have problems, send mail to ????????@lists.nit.ca.

* Looking at the output message, you can find that your modem has been detected at ttyUSB0 and it’s init string is ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0, Max speed is 115200 and various other info. But in my case(model ZTE G218) this init string caused problem, so i replaced it with at+crm=150, which i was using in windows. The initial strings are different for different models. For our internal modems, a default string ATZ is used.
* next, you have to create a modem and the connection. You can do this in the GUI or if you have experience, edit the /etc/wvdial.conf file according to the information above. This way you can connect to the computer using CDMA mobile in linux.