Simplify Curve options

Note:

To restore the filter default settings, click Edit > Reset Settings in the Filter window.

All: Simplifies the curve for the entire time range.
Time Slider: Simplifies the curve for the time range defined by the Playback Start and End times of the Time Slider.
Start/End: All keys within the specified time range (start time/end time) are simplified.
Start Time: Specifies the start of the time range. This is available only if Start/End is on.
End Time: Specifies the end of the time range. This is available only if Start/End is on.

Classic: Removes excess keys using the algorithm used in previous versions of Maya. Use this method on light data sets, such as keyframe animations, which don’t have keys on every frame.
Dense Data: Removes excess keys using an algorithm designed for dense data sets, such as motion capture data, which have a key on every frame. This method may also work well if the Classic method doesn’t give you the desired results.

Time Tolerance: The amount (in seconds) that the timing for the keys is averaged when the selected curve is simplified. The higher the Time Tolerance, the sparser your keys and the less your resulting curve resembles the original curve. The default Time Tolerance is 0.05.
Value Tolerance: The amount (in your current working units) that the values of the keys are averaged when the selected curve is simplified. The default Value Tolerance to 0.01.