Problems with Resize-Filter and Aspect Ratio Calculation

[pstein]

I dragged an Xvid encoded Avi video with resolution 704*384 onto Avidemux und wanted to resize it.

I activated Filter "swsResize". Is this the correct/only Resize Filter or are there some others/alternatives?

I checked "Lock aspect ratio" with from=16:9 to=16:9
and set the width to 624. Much to my surprise the Height is automatically adjusted by Avidemux to 340.
When I am right the the correct Height for a 16:9 video is 352 and NOT 340.

Why does Avidemux adjust the wrong Height?
I can set Height to 352 only when I uncheck "Lock Aspect Ratio"

So I think this is a bug.

Peter

[Jan Gruuthuse]

If your card support it:
nvidia: Transform: vdpau: Resize
OpenGL : OpenGL Resize

Don't have access to a source video 704*384.
Tested in Avidemux v2.6.0 (r8349) with 1920x1080 (16:9):

[Bagger]

If your card support it:
nvidia: Transform: vdpau: Resize
OpenGL : OpenGL Resize

How do you add these options, or where are they.
I would have thought you mean in filters, but there is no nvidia option and the opengl option is empty.

[Jan Gruuthuse]

card (video card) : http://en.wikipedia.org/wiki/Nvidia_PureVideo (nvidia = brand of GPU)
If OpenGL drivers installed for your video card:
Edit -> Preferences -> [Video] ->Video Display: VDPAU or OpenGL, if you get crashes with OpenGL select original setting.

[v] Decode video using VDPAU
[v] enable openGL support (if this option is available, select it, even if you don't have Video Display: OpenGL working.

[styrol]

How do you add these options, or where are they.

VDPAU = Video Decode and Presentation API for Unix ââ,¬â€œ so it's no option for Windows user, isn't it... (and yep, this is the Windows section of the forum).

[mean]

Your source material does not have square pixel
i.e. it is 704x480 but displayed at 848x480 or similar if it is 16:9

So either you resize it to 848*480 before encoding
or if it is mkv, you can force display to being 848 letting the video as it is
(just copy audio & video, configure button near container)

The player will resize it on playback

[pstein]

If OpenGL drivers installed for your video card:
Edit -> Preferences -> [Video] ->Video Display: VDPAU or OpenGL, if you get crashes with OpenGL select original setting.

Thank you, but:

How do I find out if OpenGL drivers are installed (and used)? I run Avidemux under 64bit Win7
with no video card but using the embedded graphic GPU of the Intel core i5 CPU.
When I go to
Edit -> Preferences -> [Video] ->Video Display
then currently "OpenGL" is selected.

But when I go to Filters-->OpenGL
then there is NO available filter.

So how else do I select OpenGL resize filter?

Peter