c - opencvResize() problem -

i trying use opencv2, built on ubuntu 10.04 simple program going reads exisitng image, creates image , resize original image 2(both width , height). below code. upon execution, don't see resized image window.

# include "stdio.h" #include "opencv2/highgui/highgui_c.h" #include <opencv2/imgproc/types_c.h>  int main( int argc, char** argv ) {   iplimage* img = 0;   iplimage* dst_img = 0;     if( argc < 2 ) {     printf( "usage: accepts 1 image argument\n" );     exit( exit_success );   }    img = cvloadimage( argv[1],1);   if( !img ) {     printf( "error loading image file %s\n", argv[1]);     exit( exit_success );   }    dst_img = cvcreateimage(cvsize(img->width*2,img->height*2),img->depth,img->nchannels);   if( !dst_img ) {     printf( "error loading output image file \n");     exit( exit_success );   }     cvresize(img,dst_img,cv_inter_linear);     cvnamedwindow( "original image", cv_window_autosize );   cvnamedwindow( "rescaledimage", cv_window_autosize );    cvmovewindow( "original image", 720, 515 );   cvmovewindow( "rescaledimage", 1500,1200 );    cvshowimage( "original image", img );   cvshowimage( "rescaledimage", dst_img );    cvwaitkey( 0 );    cvreleaseimage( &img );   cvreleaseimage( &dst_img );    cvdestroywindow( "original image" );   cvdestroywindow( "rescaledimage" );    return exit_success;   } 

i using cvcreateimage(), & cvresize() correctly above?

how can resize input image 2 in both directions?

any pointers on web(blogs,tutorials) , books opencv has lot of sample code 1 can use study opencv hands-on?

cvmovewindow( "rescaledimage", 1500,1200 );  

my mistake. thought dimension of window/image. position of window on screen. changed -

cvmovewindow( "rescaledimage", 100,100 ); 

both windows fine now!