Thread: Image Resizing
View Single Post
Old 21st January 2018
Graham_of_Rainham's Avatar
Graham_of_Rainham Graham_of_Rainham is offline
Join Date: Nov 2007
Location: Rainham
Posts: 7,880
Thanks: 623
Thanked 913 Times in 705 Posts
Likes: 2,180
Liked 1,513 Times in 862 Posts
Re: Image Resizing

Consider the situation of the person who has an image straight from the camera at: 5568 x 3712, which is also a 3:2 aspect ratio.

To get that down to 3840 2160, 1600 x 1200, 1400 x 1050 or 1024 x 768 (or any other ratio) requires a resize... So just how do you squash 5568 pixels into 1600 pixels ?

Each original pixel needs to be interpolated by a factor of 3.48, but exactly how do you choose which method is best?

There are a lot of different algorithms, some are good at some image content and others for different content...

So: If you are only viewing the image on a monitor which has a different resolution to the projector, you may get a nasty surprise, on club night, when the rigging lines of the yachts in the harbour look like a staircase.

I've seen many examples of regular patterns (railings, corrugated sheeting, etc.) that when compressed takes on the look of a bar code.

I've not found a "Learned Work" from any reputable source, that provides any guidance on this. The RPS is notably quiet on the whole subject...

We often repeat the mistakes we most enjoy...
Reply With Quote