Avisynth and mod 16 bug !

[Dark-Cracker]

hi,

it seems to me there is a bug if the resize was not modulo 16.

tested with avisynth 2.5.4 and 2.5.5

this :

avisource("ouest_sample.avi")
bilinearresize(500,400)

return a black screen instead of the video, because 500 was not divisible by 16.

while is i change 500 by 496 (modulo 16) all working fine and my video is displayed.

can someone could confirm this bug ?

Bye.

[sh0dan]

What colorspace?

Which decompressor? (Vdub / File / File Information)

Resize should be reliable at least down to mod4 , so your example should work.

[baz00ie]

I'm able to get 500x400 video using your sample script in both YUY2 and YV12 colour spaces.

What is the colour space of your video source? Perhapes a conversion is in order.

baz

[ARDA]

I've had a image with distortions in mod4 and was due to last xvid decoder .I've simply unistalled xvid; any other decoder no problem at all; including old xvid versions.
I hope this can be usefull.
ARDA

[Dark-Cracker]

hi,

yes sorry i have forget to give more informations :)

i am under winXP, yes the clip is in yv12 if i try to play it in mpc or wmp7/8 it show me a black screen , with the right lenght of the sample but it doesn't play it (i can only seek but it stay on "pause").

but under vdubmod i can open the clip and it show me a picture (bug with wrong colorconversion)

i have put the screenshot here :
500*400 in yv12
http://dark.pluridis.org/~darkangel/bad.png

496*400 in yv12
http://dark.pluridis.org/~darkangel/good.png

if i convert it in rgb32 the sample can be played fine (even in 500*400), so i suppose it's a problem in the dshow filter not in avisynth :)

if i open the script in graphedit it show me :

filename => avi decompressor => color space converter => video render

if i click on "property" on avi decompressor it say me :

in : YV12 500*400, 12 bits
out : RGB32 500*400, 32 bits

and solor space converter say me :

in : RGB32 500*400, 32 bits
out : RGB32 500*400, 32 bits

strange ! i hope this can help u :)

Bye.

[Manao]

Dark-Cracker : ARDA found the cause of your problem. Until the last beta of XviD, the XviD's decoder is buggy with width non dividable by 8.

It's corrected in the last RC1, so I would adivse you to get it in order to solve your issue.

[sh0dan]

Most (if not all) graphic cards require Mod16 to be able to play YV12 and YUY2 material.

[Dark-Cracker]

@Manao
ok thank u i will test this :)

@sh0dan
my graphic card is a geforce 5600 fx.

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