Image Resize Frontmatter

Hello.
I have setup a blueprint like this:
fields:
…
.Image:
type: file
label: Image
destination: ‘@self’
multiple: false
accept:
– image/*

How can I resize the placeholder like {{ image.Bild|first.path }} with .cropResize(300, 300)?

I cannot use page.media because there are some additional fields for every element (title, price, ...)

Thank you!

This is how I accomplished a similar thing on my site:

page.media[page.header.default_photo].cropResize(300,300)

page.header.default_photo contains the image filename. By passing the filename into page.media I found I could apply any media process to it.

I'm new to Grav so I don't know if this is the best way, but it works.