From wsc4 at optusnet.com.au  Tue May  3 11:56:57 2016
From: wsc4 at optusnet.com.au (Bill Crockett)
Date: Tue, 3 May 2016 19:56:57 +1000
Subject: [MEncoder-users] Cropping,  multiple of 16 and horizontal scaling
Message-ID: <13E5BFE07D9B41978E5880D7EBFFA5CE@Tower>

Cropping a 720 x 576 mpeg-2 video to 688 x 576 produces a 733 x 576 
horizontal scaling.

>From MPlayer:
Movie-Aspect is 1.33:1 - prescaling to correct movie aspect.
VO: [gl] 688x576 => 733x576 Planar YV12

Using the divisibility rule of 16 to get 720 to 688, to cut out those black 
bars, do I have to scale the 733 to a multiple of 16?

MEncoder -sws 9 -vf crop=688:576:20

Can I leave it at the 733 x 576 horizontal scaling?

It will only be played on monitors with square pixels; not rectangular 
pixels 



From barsnick at gmx.net  Tue May  3 14:19:48 2016
From: barsnick at gmx.net (Moritz Barsnick)
Date: Tue, 3 May 2016 14:19:48 +0200
Subject: [MEncoder-users] Cropping, multiple of 16 and horizontal scaling
In-Reply-To: <13E5BFE07D9B41978E5880D7EBFFA5CE@Tower>
References: <13E5BFE07D9B41978E5880D7EBFFA5CE@Tower>
Message-ID: <20160503121948.GC17539@sunshine.barsnick.net>

Hi Bill,

On Tue, May 03, 2016 at 19:56:57 +1000, Bill Crockett wrote:
> Using the divisibility rule of 16 to get 720 to 688, to cut out those black 
> bars, do I have to scale the 733 to a multiple of 16?

No, 733:576 is the display aspect ratio, applied by mplayer during
playback. 688:576 is the storage aspect ratio, and that is the one
where the "divisible by 16" rule applies.

> It will only be played on monitors with square pixels; not rectangular 
> pixels

That's something the player needs to solve, not the encoder.

Moritz