trimmd Trim Mean Difference
trimmd is the mean difference threshold for the trimming operation, and is only valid when
trim is set to
auto. The default value is
11. This value defines the difference between each row of pixels while attempting to remove the border. Decreasing this threshold makes the imgix trim algorithm more aggressive about trimming.
trimmd value may still leave a line or two of border on an image, usually due to noise in the borders from image compression.