[Avidemux] Aspect Ratio vs Playback

[Shadarr]

Have been loving this application - it replaced VirtualDub for me!

But using various settings in the plugins and the Motion & Misc menu hasn't resulted in the desired playback aspect ratio.

Attempting to set a clip to 480x272 but with a playback of 480x360 (4:3) doesn't seem to be possible...
Tried setting the filters to x272 and then Motion&Misc to 4:3, etc

Updated from 2.4.3 to 2.5.0 as well, during trying this.

Any ideas?

[guns1inger]

Outputting to what format/container ?

Played back in what player ?

Not all formats/containers allow for the AR flag, and not all players observe even if it is there.

Use something like mediainfo or g-spot to see if the AR flag is actually being set.

[guns1inger]

I cannot find anywhere to set the display aspect ratio for Xvid encoding in the output configuration of AVI Demux. I can change the PAR, but that doesn't help playback. However a quick trip through Mpeg4Modifier makes it playback correctly is a DAR aware player such as The KM Player.

[Shadarr]

Outputting to what format/container ?

Played back in what player ?

Not all formats/containers allow for the AR flag, and not all players observe even if it is there.

Use something like mediainfo or g-spot to see if the AR flag is actually being set.

Thanks, I forgot to mention what player/format :P

MP4, tested playing with Media Player and VLC

Tried using the couple different Resize plugins in Filters, and set them for 4:3 and 1:1 and neither works, with output AR....

Perhaps it just cannot be done? I don't mind compressing/playing at 4:3, was just trying to save on some real estate in the compression.

Opening the output file in Gspot shows Storage and Display Aspect Ratio being the same and neither is 4:3.
Interesting, it seems to not be getting set at all.
The output is merely whatever the 'resize' plugin is, and it seems be ignoring the 1:1/4:3 setting as well as the Motion&Misc setting

[guns1inger]

The resize plugins are only for resizing the video prior to encoding. They have no effect on encoding settings like Aspect Ratio. These have to bve set in the encoder settings.

You don't actually win using the method you are attempting. If anything, you lose. When the video is played back, it is not stretched vertically - it is compressed horizontally. Instead of getting 480 x 360 you get something much smaller - 360 x 272. And you really do not save any great amount in file sizes.

[Shadarr]

The resize plugins are only for resizing the video prior to encoding. They have no effect on encoding settings like Aspect Ratio. These have to bve set in the encoder settings.

You don't actually win using the method you are attempting. If anything, you lose. When the video is played back, it is not stretched vertically - it is compressed horizontally. Instead of getting 480 x 360 you get something much smaller - 360 x 272. And you really do not save any great amount in file sizes.

Thank you for that explanation - compressed horizontally? Is that specifically for Avidemux?
When you compress a VCD for instance, at 352x480, it is stretched to 640x480 (with aliasing as well).

Regardless, alas it seems that Avidemux simply is not setting the Playback Aspect Ratio (checking it in Gspot).
It seems to only be accepting what is set in the RESIZE and ignores any other 4:3 setting (in Resize or in Motion&Misc). You have to compress at 4:3 to get it (set it specifically at 480x360)...

That's too bad, as the PSP does not play 480x360, it is fussy to certain resolutions. I am able to use other applications to compress at 480x272 and playback at 4:3... I just wanted Avidemux to do it all

Thanks anyway for your input, as well

[Gavino]

Thank you for that explanation - compressed horizontally? Is that specifically for Avidemux?
When you compress a VCD for instance, at 352x480, it is stretched to 640x480 (with aliasing as well).

The point is that on playback, only the horizontal dimension is ever changed (stretched or compressed), the height is unchanged.

So 480x272 displayed at 4:3 gives 360x272 (height is still 272), just as 352x480 gives 640x480 (height still 480).

[jagabo]

The point is that on playback, only the horizontal dimension is ever changed (stretched or compressed), the height is unchanged.

That may be true on the PSP (I don't know), but in general, it depends on the player.

[guns1inger]

The KM Player does it, as does VLC and MPC HC (tested using the file created for the OP's original problem).

Actually, all play the mp4 file assuming a 1:1 PAR with no DAR set, as that is what AVI Demux produces, however when told to display the image 4:3, they compress the image horizontally. The same video encoded to Xvid with the 4:3 DAR set does the same thing in all three players, but without the need for manual intervention.

[jagabo]

On my system, XP Pro, SP3, a 480x272, 4:3 DAR, Xvid AVI file (created with VirtualDub and Xvid):

Using quartz.dll as the AVI reader and Xvid as the decoder MPCHC opens a 480x272 window with a 360x272 image pillarboxed in the window. Selecting Zoom -> 100% resizes the window to 480x360 and displays the picture over the full window. Using quartz and ffdshow results in the window opening at 480x360 with a full image. Using MPCHC's internal AVI reader and Xvid decoder opens a 480x360 window with the video filling it.

Opening the video in VLC gives a 480x360 window with the video filling it.

Using its internal Xvid decoder or Xvid, KMPlayer opens a 360x272 with the image filling it. Using ffdshow it opens a 480x272 window and the video fills the window (wrong DAR).

None of this really matters with Windows anyway. You can always resize the window if the default size not to your liking.