Oversample

Oversample Operator

This operator upsamples a real or complex image through frequency domain zero-padding. The algorithm takes into account the value of the Doppler Centroid Frequency when padding the azimuth spectrum. For real image, the upsampled image is also a real image, and for complex image, the up sampled image is a complex image.

Oversampled Image Size

User can specify the output image size by selecting

• the user specified output image dimension, or
• the row, column ratios by which the input image should be multiplied, or
• in terms of output image range and azimuth pixel spacings.

Parameters Used

If the upsampled image is output by image size, then the following parameters are used by the operator:

1. Source Bands: All bands (real or virtual) of the source product. User can select one or more bands for producing upsampled images. If no bands are selected, then by default all bands are selected.
2. Output Image By: The method for determining upsampled image dimension.
3. Output Image Rows: The row size of the upsampled image.
4. Output Image Columns: The column size of the upsampled image.
5. Use PRF Tile Size: Checkbox indicating the tile size in processing is PRF by image width. In not checked, system computed tile size is used. In case the image is large, system computed tile size should be used to avoid memory problem.
   

If the upsampled image is output by image dimension ratio, then the following parameters are used by the operator:

1. Source Bands: All bands (real or virtual) of the source product. User can select one or more bands for producing upsampled images. If no bands are selected, then by default all bands are selected.
2. Output Image By: The method for determining upsampled image dimension.
3. Width Ratio: The ratio of the upsampled image width and the source image width.
4. Height Ratio: The ratio of the upsampled image height and the source image height.
5. Use PRF Tile Size: Checkbox indicating the tile size in processing is PRF by image width. In not checked, system computed tile size is used. In case the image is large, system computed tile size should be used to avoid memory problem.
   

If the upsampled image is output by pixel spacing, then the following parameters are used by the operator:

1. Source Bands: All bands (real or virtual) of the source product. User can select one or more bands for producing upsampled images. If no bands are selected, then by default all bands are selected.
2. Output Image By: The method for determining upsampled image dimension.
3. Range Spacing: The range pixel spacing of the upsampled image.
4. Azimuth Spacing: The azimuth pixel spacing of the upsampled image.
5. Use PRF Tile Size: Checkbox indicating the tile size in processing is PRF by image width. In not checked, system computed tile size is used. In case the image is large, system computed tile size should be used to avoid memory problem.