Basic picture similarity analysis

1

I want to compare two images and get a % value as to how similar they are. The source of the images are videos.

Example: 1080p raw video

  1. encoded with x264 in 1080p
  2. encoded with VP9 in 240p

I know how to extract images from the videos, I just mention it, so you know one image will be high quality (1080p) and the image I compare it to will be low qulity, potentially with block artefacts (240p).

I attached two images so you know what I am dealing with.

I just want very basic full image comparison (and maybe a few parameters and algorithms to play with) that spits out a % value at the end.

I would prefer code examples in Java but I guess the API is similar between Python and Java, so I could work it out.

Example images:

image

image
image1920Ă—1080 70.3 KB

2

I should note, that the images I want to compare are identical, except the different size and compression. They are NOT from different time stamps in the video.

Maybe in some pictures there is a little logo added to a corner of one of the pictures for the comparison, but that’s it.

It’s like I take a high-res picture and scale it down and use high JPEG compression to save it again and then compare the two pictures.

3

please, put your images here, not on an external site.

then, “similarity” is a very broad term. what exactly are you looking for ?
what is the purpose of your program ?

4

I wanted to insert the images in the text but I wasn’t allowed as newbie.

I want to find duplicates of the same video (or image). I am already comparing by resolution, duration and much more but not by actual visual comparison.

I don’t want to identify any objects in the image or do something fancy. I just want a % value that tells me how similar two images are.

5

yea, just make 2 posts …

sounds like something from img_hash

1 Like
6

so… PSNR is a common metric, and so is SSIM.

a percentage is too simple and too ambiguous.

1 Like
7

Can you direct me to code samples both for img_hash and PSNR/SSIM?