View Window - Transform | Rotate...                    J

Main Window - Image | Batch Process - Batch Steps - Add | Transform | Rotate...

 

 

This dialog box allows you to rotate an image.

 

Angle (CW). Angle (clockwise) of rotation, in .01-degree increments.

 

Background color. When rotating to an angle that results in new image dimensions that do not match the original aspect ratio, a background is added. Use this button to select the background color.

 

Interpolation. Use this drop-down list to select the type of interpolation (resampling) which ThumbsPlus will do when rotating:

 

Nearest Neighbor (fast)

This is the fastest resize method, but the least pleasing because it performs no pixel interpolation. Usually results in significant "jaggies".

Bi-linear (good)

Computes weighted average of four pixels, based on computed position from the original source. This is slower but better than Nearest Neighbor, and considerably faster than bi-cubic.

Bi-cubic (better)

Computes cubic convolution of sixteen pixels, based on computed position from the original source. This produces the most accurate results, but is significantly slower than bi-linear interpolation.

 

 

Clear. Use this button to reset the rotate angle back to 0.00.

 

ThumbsPlus remembers the last settings from this dialog box so that you can re-use them for additional images, or for batch processing.

 

Note: If you rotate or resize a 256 (or fewer) color image and select interpolation, ThumbsPlus will automatically promote it to 24-bit (truecolor) to be able to interpolate intervening pixels. You can then use the Image | Color Depth selection from the view window menu to adjust the colors to the number you desire. Likewise, ThumbsPlus will promote any grayscale image less that 256 levels to an 8-bit grayscale image.