To improve the aerial photography you can use the resampling technique and enhance the raster display quality. The resampling methods reduces distortions in the raster data and enhances the display of raster data. You can notice the difference, when you zoom in beyond the resolution of the individual pixels in the source raster file. Once you have applied the resampling technique on the source raster you can zoom in on an area in the raster and feel the difference in display quality.
How to Enable/Disable the Resampling Method
The Display Resampling Method option is disabled by default. It depends on the Enable block access check-box. To enable it, click on the PRO tab, click Options, and then click Preferences to open the Raster Preferences dialog box. On the Display tab, select the Enable block access check-box and choose the required resampling methods from the Display Resampling Method drop-down list. We suggest using Cubic Spline (Global) resample method for most of the dataset. The selected resampling method becomes the default options.
You need to restart MapInfo Pro Advanced to make the preferences settings to take effect.
When Display Resampling Methods is enabled, Raster Quality button is displayed in the Display group on the RASTER tab. You can apply the required resampling method from the drop-down list on a continuous or imagery type raster.
Improving Raster Quality by using Resampling Method
Image Resampling Method is the process of approximation of a pixel's color and intensity based on the values at surrounding pixels. It results in enhanced raster quality. The image resampling method works by interpolating the pixel values while transforming the raster dataset to produce enhanced image. You can choose an appropriate resampling technique based on your input data. MapInfo Pro Advanced supports the following resampling method:
- None - No resampling method is applied to the raster.
- Nearest Neighbour - It calculates the value of each cell by performing a nearest neighbor assignment. This is the most basic technique that requires the least processing time of all the interpolation algorithms. This technique selects the nearest pixels to replace the original pixels when images are zoomed.
- Bilenear - It considers the closest 2x2 neighborhood and calculates the new value of a cell based on a weighted distance average of the four nearest input cell. It provides smoother looking images than nearest neighbor. You should use this method for continuous data.
- Cubic Spline (Global, Local) - It considers the closest 4x4 neighborhood and calculates the new value of a cell based on fitting a smooth curve through the 16 closest input cell. It requires more processing time. You should use this method for continuous data.
- No Raster Smoothness