set pg [getSelectedPGroup]
if {$pg==0}\
	{
	bell
	post3DEInfoRequester " \n    Error, there is no Pointgroup selected.    \n"
	return
	}

set fobj [getSelectedFobj]
if {$fobj==0}\
	{
	bell
	post3DEInfoRequester " \n    Error, there is no Sequence selected.    \n"
	return
	}


set no_frames_tracked [post3DEPromptRequester "Delete all points with less than x frames tracked:"]

set no_frames [getFobjNoFrames $fobj]

set string [post3DEPromptRequester "Define Frame Range (1 $no_frames):"]

set frame_a [lindex $string 0]
set frame_b [lindex $string 1]

if {$frame_b<=$frame_a} { set frame_b [expr $frame_a+1] }
if {$frame_b>$no_frames} { set frame_b $no_frames }
if {$frame_a<0} { set frame_a 1 }
if {$frame_a>=$frame_b} { set frame_a [expr $frame_b-1] }
if {$frame_a<1} { set frame_a 1 }

for {set point [getFirstPoint $pg]} {$point!=0} {}\
	{
	set block [getPointPosition2DBlock $pg $point $fobj 1 $no_frames]
	set anz 0
	
	for {set i [expr $frame_a-1]} {$i < [expr $frame_b-1]} {set i [expr $i+1]}\
		{
		set v2 [lindex $block $i]
		if {[lindex $v2 0]!=-1}\
			{
			set anz [expr $anz+1]
			}
		}
	
	set p2 [getNextPoint $pg $point]
	
	if {$anz<$no_frames_tracked}\
		{
		if {$anz>0}\
			{
			deletePoint $pg $point
			}
		}
		
	set point $p2
	}