Figure 1: Comparison between single-channel-matched filtering and multichannel MTXF filtering for a four-channel simulation of a patch of the sky as observed by the Planck 30, 44, 70 and 100 GHz detectors. The top row of images show the simulated patches. The second row shows just the point sources present in the simulations. The third row shows the patches after being filtered with single-channel-matched filters. The fourth row shows the patches filtered with the corresponding MTXF. The -and -axes are in pixel units (pixel size = 3.435 arcmin).