What Algorithm is Used for Transform?

[KostFan2]

• Background: In Photoshop when you transform you are resizing the image which resamples it using one of Photoshop 25.3.1’s seven algorithms.

• Question #1: Which one of Photoshop’s serven algorithms is being used?
• Possible answers:
  a) The last one used in Photoshop is the one Transform uses.
  b) “Automatic” is used.

• Question #2: If “Automatic” is the answer, does this use one of the following two depending if you enlarging the image or reducing it?
• Enlarge: uses Bicubic Smoother
• Reduction: uses Bicubic Sharper

• Question #3: If the answer is “The last one used in Photoshop”, then the customer has to add an important step to their workflow.  They have to create a fake document, open an image, and perform a resizing on that document using the algorithm they want to use for the transform in the real document.  This adds the correct algorithm to Photoshop’s “the last one used” buffer.

[D Fosse]

You set the default resampling algorithm in Preferences. This is used where it's not otherwise specified.

[Bojan Živković]

I would like to mention that this is a user-to-user forum, with occasional visits from employees.

[Jeff Arola · Accepted solution]

Also worth mentioning is that Photoshop 7 has none of the Interpolation methods listed in your post.

In modern versions of Photoshop like the most recent 2024, one can chosse the Interpolation method to use for Transform in the tool options bar when Transform is enabled by going to, for example, Edit>Free Transform.

[Bojan Živković]

I think OP is talking about the following screenshot of "Photoshop's 7 algorithms".

[KostFan2]

Bojan:
You are correct. Thank you for clarifying

[Jeff Arola]

Your probably right since while i was posting, the OP changed the post from photoshop 7 to photoshop 25.3.1

[KostFan2]

Jeff:

Thank you. This is very helpful information.  I was hoping Photoshop had this ability.  Last week I spoke with Tier II phone support and they said it did not exist.  I edited the post to specify the current photoshop version so others reading the post would not be confused as well.