Upscaling on GPU with bicubic interpolation

Hi everybody,

i need to upscale a texture of dim 320x240 to 1920x1080 (so a scaling factor of x6, x4.5). I'd like to do the upscaling with a bicubic interpolation since the bilinear one generates visible artifacts with a scaling factor that big.

Is there already any shader or jit.gl.pix piece of code which does the job or do i need to program my own?
If you're intrested in the subject, this is a nice explanation of bicubic interpolation and its implementation

Thanks!