libvips/cplusplus/examples/avg.cc

54 lines
983 B
C++

/*
* compile with:
*
* g++ -g -Wall avg.cc `pkg-config vips-cc --cflags --libs`
*
*/
#define DEBUG
#include <vips/vips8>
using namespace vips8;
int
main( int argc, char **argv )
{
GOptionContext *context;
GOptionGroup *main_group;
GError *error = NULL;
if( vips_init( argv[0] ) )
vips_error_exit( NULL );
context = g_option_context_new( "" );
main_group = g_option_group_new( NULL, NULL, NULL, NULL, NULL );
g_option_context_set_main_group( context, main_group );
g_option_context_add_group( context, vips_get_option_group() );
if( !g_option_context_parse( context, &argc, &argv, &error ) ) {
if( error ) {
fprintf( stderr, "%s\n", error->message );
g_error_free( error );
}
vips_error_exit( NULL );
}
{
VImage in = VImage::new_from_file( argv[1],
VImage::option()->set( "access", VIPS_ACCESS_SEQUENTIAL_UNBUFFERED ) );
double avg;
avg = in.avg();
printf( "avg = %g\n", avg );
}
vips_shutdown();
return( 0 );
}