Avidemux Forum

Avidemux => Stable branch (2.5) discussion => Topic started by: hgurol on August 02, 2012, 09:33:02 AM

Title: Aspect Ratio, how to?
Post by: hgurol on August 02, 2012, 09:33:02 AM
Is there a guide that shows how to change the aspect ratio of the video file without having a distortion on the picture?

I have source files downloaded from internet which comes in all different sizes and aspect ratios. I want to bring them to a standard. I want to change all different variations of wide screen source to 16:9 and all non-wide screen source to 4:3.

I tried a couple of time with different settings but no success. Either the objects in the pictures stretches or shrinks.

Is there a guide that I can read and learn how to do it properly?

Thanks...

Title: Re: Aspect Ratio, how to?
Post by: Jan Gruuthuse on August 02, 2012, 10:05:10 AM
you have 3 tools for doing so, could be other solutions to?
Adding black borders, resizing or cropping.
Some info can be found here: VideoHelp: Determining Aspect Ratios and Resolutions (http://forum.videohelp.com/threads/120047-Determining-Aspect-Ratios-and-Resolutions)
Title: Re: Aspect Ratio, how to?
Post by: hgurol on August 02, 2012, 01:52:30 PM
You mean all 3 of them or one of 3? Because I'm already re-sizing them of course to 480*270 which is a 16:9 resolution.
I have no intention to crop the picture and I don't have an idea about adding black borders.

I have seen that guide, it wasn't that much helpful. Anything else you know?
Title: Re: Aspect Ratio, how to?
Post by: Jan Gruuthuse on August 02, 2012, 02:35:04 PM
more technical: http://www.iki.fi/znark/video/conversion/
Not really, I keep clips as they are. Just on few occasions when samsung flat screen media player (DLNA) is not playing content due to not supported format/size, I do a resize to the closest fit, up/down.

black border usage:
Quote from: Jan Gruuthuse on August 02, 2012, 09:49:53 AM
Quote
Quotesource: Width: 640 pixels x Height: 480 pixels
The program tells you: this is not up to dvd specification. DVD is very strict!
Match output to Width: 720 x Height: 576 pixels with one of these options in
Video Output: Filters:
  • swResize, vdpau: resize or openGL resize: Resize: W: 720 H:576, last 2 if hardware support this.
  • Add Borders:
    720-640= 80/2 = 40 on Left and Right Border
    576-480= 96/2 = 48 on Top Border and Bottom Border
Title: Re: Aspect Ratio, how to?
Post by: hgurol on August 02, 2012, 07:27:22 PM
These source files are already encoded and download from internet, here and there. Im re-encoding and re-sizing them and also want to bring a standard to their resolutions and aspect ratio. They are to be streamed on the internet when I finish them. So the target is browser media players and they are to be watched full screen %99 of the time.

Is cropping and/or adding black borders are only way to avoid the shrinks and stretches while changing aspect ratio?
I guess I really need a dummy-proof guide, not a more technical article.
Title: Re: Aspect Ratio, how to?
Post by: styrol on August 03, 2012, 07:39:56 AM
QuoteIs cropping and/or adding black borders are only way to avoid the shrinks and stretches while changing aspect ratio?
Yep.

QuoteI guess I really need a dummy-proof guide, not a more technical article.
https://trac.handbrake.fr/wiki/HandBrakeGuide
If you do not cut your videos (Avidemux is a useful tool for this) and you're only converting files (using some filters) you might work with HandBrake at all.