hi,

subj should be impliment in blender, i wonder why it still not realized.

so, for now i did fast and dirty simplification script, it works ok, but far from perfection, cause utilize polyline Douglas-Peucker simplification algorithm, taken from http://emergent.unpy.net/

hope blender developers will make normal simplify function (which any vector-editor contain, inkscape, so on…) and improve working with curves also in 3d.

so, here blend

http://eggnot.com/virt/blender/del-keyframes.blend

and here code:

```
# small script you can simplify IPO - curves
#
# aleksey grishchenko (http://eggnot.com/) 2006
#
# keep in mind simplifycation algorithm
# based on Douglas-Peucker POLYLINE simp. procedure,
# so curved IPO's will never will be better,
# but it can be ok for cleaning after Game Physics IPO recording
# or Motion Capture or so...
# once executed, script rebuild all curves of fist IPO
# for selected object and create new IPO name old_name+"simply"
# for next execution it creating IPO's old_name+"simply."+NNN
# so you can try different TOLERANCE value for best result
TOLERANCE = 0.1
#press ALT+P to continue!
###############################################################
# dist_lseg and douglas was taken from http://emergent.unpy.net
# without any changes
###############################################################
def dist_lseg(l1, l2, p):
x0, y0, z0 = l1
xa, ya, za = l2
xi, yi, zi = p
dx = xa-x0
dy = ya-y0
dz = za-z0
d2 = dx*dx + dy*dy + dz*dz
if d2 == 0: return 0
t = (dx * (xi-x0) + dy * (yi-y0) + dz * (zi-z0)) / d2
if t < 0: t = 0
if t > 1: t = 1
dist2 = (xi - x0 - t * dx) ** 2 + (yi - y0 - t * dy) ** 2 + (zi - z0 - t * dz) ** 2
return dist2 ** .5
def douglas(st, tolerance=.01, first=True):
if len(st) == 1:
yield st[0]
return
l1 = st[0]
l2 = st[-1]
worst_dist = 0
worst = 0
for i, p in enumerate(st):
if p is l1 or p is l2: continue
dist = dist_lseg(l1, l2, p)
if dist > worst_dist:
worst = i
worst_dist = dist
if first: yield st[0]
if worst_dist > tolerance:
for i in douglas(st[:worst+1], tolerance, False):
yield i
yield st[worst]
for i in douglas(st[worst:], tolerance, False):
yield i
if first: yield st[-1]
########################################################33
from Blender import Object, Ipo
ob = Object.GetSelected()[0]
ipo = ob.getIpo()
newIpo = Ipo.New("Object",ipo.getName()+"-simply")
for curve in ipo.getCurves():
print "->", curve
poly = []
for beZier in curve.getPoints():
polyx = beZier.vec[1][0]
#print beZier.getPoints() # deprecated???
poly.append([polyx,curve[polyx],0])
#print polyx
#curve.delBezier(polyx) #deprecated???
#ipo.delCurve(curve.name)
newCurve = newIpo.addCurve(curve.name)
for x,y,z in douglas(poly, TOLERANCE):
newCurve.addBezier((x,y))
print "new point x,y:", x, y
newCurve.recalc()
```