Resize image

void resize(InputArray src, OutputArray dst, Size dsize, double fx=0, double fy=0, int interpolation=INTER_LINEAR )
       - The function resize resizes the image src down to or up to the specified size.
Parameters:

• src – input image.
• dst – output image; it has the size dsize (when it is non-zero) or the size computed from src.size(), fx, and fy; the type of dst is the same as of src.
• dsize – output image size; if it equals zero, it is computed as:
  
  
  Either dsize or both fx and fy must be non-zero.
  
• fx – scale factor along the horizontal axis; when it equals 0, it is computed as
  
  
• fy – scale factor along the vertical axis; when it equals 0, it is computed as
  
  
• interpolation – interpolation method:
  
  • INTER_NEAREST - a nearest-neighbor interpolation
  • INTER_LINEAR - a bilinear interpolation (used by default)
  • INTER_AREA - resampling using pixel area relation. It may be a preferred method for image decimation, as it gives moire’-free results. But when the image is zoomed, it is similar to the INTER_NEAREST method.
  • INTER_CUBIC - a bicubic interpolation over 4x4 pixel neighborhood
  • INTER_LANCZOS4 - a Lanczos interpolation over 8x8 pixel neighborhood

Example:

resize(src, dst, dst.size(), 0, 0, interpolation_method);