What is the equivalent of LaTeX's "\includegraphics*[scale = 0.3, trim = 0 100 0 200"]{tiger.png}?

Questions
,
1

I use a lot of screenshots in my documents (technical specifications of a software application). They all differ in dimensions, sometimes in resolution (72/144dpi), but I need them to have a consistent scale (the larger images are scaled down to fit, so that’s ok).

Often, I need to trim them as well.

As far as I understand, the scale in #image(width: 30%, …) refers to the size of the container, similar to LaTeX’s [width = 0.3\linewidth] option. But that’s not what I need.

Any suggestions to get this functionality would be more than welcome!

Thanks,
Peter.

2

Hi @pejef,

I’m not exactly sure what this LaTeX command does, but if you want to scale an image based on its size, you could measure the image’s dimensions and use the scaled measured size as the image’s width/height.


#let scale(scale: 1.0, img) = context {
  let size = measure(img)
  set image(width: size.width * scale)
  img
}

#scale(scale: .3, image("test.png"))

“Trim” can be emulated by enclosing the image with a box and using inset and clip.

#box(clip: true, inset: (left: -2cm), image("test.png"))
2 Likes
3

Ah, nice. So I guess I can make a function with optional arguments that combines the clipping and scaling (and rotation if needed) and combines all this.

Thanks!

4

Unfortunately, I can’t make a function that combines the scaling and trimming.
Let’s say I want to get this (let’s assume that the options are mutually exclusive).

#let includegraphics(path, trim: (0pt, 0pt, 0pt, 0pt), scale: none, width: none, height: none) = {
}

With the trim being relative to the original size of the image.

Some examples of usage:

#includegraphics("my-image.png", scale = 0.7)
#includegraphics("my-image.png", trim = (10pt, 0pt, 70pt, 100pt))
#includegraphics("my-image.png", trim = (10pt, 0pt, 70pt, 100pt), scale = 0.8)
#includegraphics("my-image.png", height = 7cm)
// etc

To do this, I would have to get the original dimensions of the image (without scaling).
Then trim as specified.
Then scale the trimmed image, either by the given scale, either by calculating the scale as (given size/trimmed size)

However, I can’t seem to get the original dimensions of image?

Thanks,
Peter.

5

The only way I know of to trim an image in Typst is by using this package:

I don’t know if it would satisfy your needs out of the box, but it might help you get to your solution.

6

Doesn’t measure(img) do what you want?

7

Good suggestion!

  // Measure the natural size of the image
  let img = measure(image(path))
  let orig_w = img.width
  let orig_h = img.height

unfortunately, Typst is not happy:

error: can only be used when context is known
   ┌─ barcode.typ:43:12
   │
43 │   let img = measure(image(path))
   │             ^^^^^^^^^^^^^^^^^^^^

Mission impossible?

8

As the error says, you must provide a context:

context {
  let img = measure(image(path))
  let orig_w = img.width
  let orig_h = img.height
}

Note that you cannot use orig_w or orig_h outside of the context block. You must surround with context the whole piece of code that uses the context.