what each filter does:
minimal width (points)
If an integral region contains less points than this value, it is filtered out. When the value is 1 point, this filter has no effect.
merging distance (ppm)
iNMR adds more space on both sides of each integral. If two integrals are very near to each other, they will be fused. When the value of this filter is 0 ppm, it has no effect.
maximum allowed ratio
This value corresponds to the normalized intensity of the highest integral. All integrals whose normalized intensity is less than one are eliminated. The highest the value, the more integrals are created. When you set this value = 5, for example, the weak integrals (less than 20% of the tallest one) are eliminated. You can set values higher than 200 when you run this command from the console, yet you will normally prefer smaller values. Negative integrals are never created by the automatic routine.