[MPlayer-users] Obscure bug in -vo null

[RC]

Okay, here's a strange and obscure bug for everyone to look at...  First
off, I'm currently using MPlayer dev-CVS-041008-12:19-3.2.2

This seems to be a bug in -vo null, when used in combination with
'cropdetect' AND 'scale'.  It might have other effects, but that's the
one I've come across.  There is an easy work-around, and that is using
-vo md5sum instead.  So, there's no big hurry to fix it, but it just
takes 2 or 3 of these little weird bugs to make using mplayer terribly
frustrating.

Let's try this simple case for crop-detection:

mplayer -vf pp=md,scale=-2:480,cropdetect -frames 10 -ss 120 Farscape\
2004Oct18_01\:00.01.mpeg -vo null


SwScaler: BICUBIC scaler, from Planar YV12 to Planar 444P using MMX2
VO: [null] 640x480 => 640x480 Planar 444P  [fs]
crop area: X: 1..602  Y: 51..479  (-vf crop=592:416:6:58)%  0.0% 0 0 70%
crop area: X: 1..602  Y: 51..479  (-vf crop=592:416:6:58)%  0.0% 0 0 70%
crop area: X: 1..602  Y: 51..479  (-vf crop=592:416:6:58)%  0.0% 0 0 93%
crop area: X: 1..637  Y: 51..479  (-vf crop=624:416:8:58)%  0.0% 0 0 93%
crop area: X: 1..637  Y: 51..479  (-vf crop=624:416:8:58)%  0.0% 0 0 92%
A: 411.0 V: 411.0 A-V:  0.012 ct:  0.124   11/ 11   0%  0%  0.0% 0 0 92%

Exiting... (End of file)

Well, I can tell you those aren't the dimentions I'm looking for... 
That crops the border off the top, but leaves the border across the
bottom.  Changing only the -vo gives the correct results:

mplayer -vf pp=md,scale=-2:480,cropdetect -frames 10 -ss 120 Farscape\
2004Oct18_01\:00.01.mpeg -vo md5sum

SwScaler: BICUBIC scaler, from Planar YV12 to Planar YV12 using MMX2
VO: [md5sum] 640x480 => 640x480 Planar YV12  [fs]
crop area: X: 3..556  Y: 52..402  (-vf crop=544:336:8:60)%  0.0% 0 0 93%
crop area: X: 3..556  Y: 52..403  (-vf crop=544:336:8:60)%  0.0% 0 0 93%
crop area: X: 3..556  Y: 52..405  (-vf crop=544:352:8:52)%  0.0% 0 0 93%
crop area: X: 3..632  Y: 52..411  (-vf crop=624:352:6:56)%  0.0% 0 0 92%
crop area: X: 3..632  Y: 52..411  (-vf crop=624:352:6:56)%  0.0% 0 0 92%
A: 411.0 V: 411.0 A-V:  0.012 ct:  0.124   11/ 11   0%  0%  0.0% 0 0 92%

Exiting... (End of file)

I have to assume the problem is something in the conversion to 444P that
happens if I use -vo null.  This isn't a problem if I don't put
scale=-2:480 before cropdetect, but it is necessary.