How can I automate resize and crop of headshots to the same proportions? [duplicate]

Question

What options do I have to process a folder of shots that include faces taken at various proportions and positions (e.g., some of full body, some of head and shoulders) and resize and crop them all so that the head to chin ratio is 2/3rd the height of the total photo?

Essentially, I want to turn all the photos into 2 inch wide x 3 inch tall headshots with the heads equally positioned and proportioned (i.e., the top of the head to the chin is 2 inches tall).

I've been doing it manually in several steps, but if there is some or all of the process I can automate I would appreciate suggestions.

Answer 1

If I understand your question correct, I cannot provide an out-of-the-box solution, but a reasonable starting point. The program “facedetect” (https://www.thregr.org/~wavexx/software/facedetect/) will give you coordinates of the detected faces. You could use this data to write a little script that does the cropping to your taste.

On the linked site are two example scripts, one for automatically blurring out faces and one for sorting images based on the presence of faces. They may serve as a good starting point.

Answer 2

You can do it in Darktable. The resizing is automatic but not the crop, also you have a lot of functions to make other adjustments in your fotos. I'm not aware of the RawTherapee, but you could also give it a look. Not a "click and done" solution, but my 2 cents.

Crop in Darktable here

Watermark in Darktable here

Answer 3

You can use IrfanView, it has many features and batch processing too.

UPDATE : @Olivier has right, I should give an example. So here : https://blogs.mcgill.ca/webeditors/2011/01/27/batch-processing/ is one of many tutorials, which you can find on the Internet.

Nowadays I croping and resizing with ACR (Adobe Camera Raw). Dependig on what computer you has, you can open 20 maybe 40 pictures (depending of picture size) and than I crop and resize first of tchem. Than synchronize change to rest of files. In this workflow I have control of each croping.