Pass a "hotspot" to Crop.crop_focus()

[sodapopcan]

Hey Kip!

The Crop.crop_focus() option type lets us pass one of a set of predetermined functions. At my work, we manually set a "hotspot" on each image for where we want the focus to be. Would you be interested in including this in Image? It's just a thought, I won't be offended if you aren't 😅

I was thinking the API could be passing a "percentage point" to :crop.

Image.thumbnail(image, "500x400", crop: {0.5, 0.5})

This would focus on the center of the image. I know that crop_focus options are sent wholesale to Vix's thumbnail operation so I'm not sure you'd ok with that inconsistency, but it seems like a good place for Image as far as discoverability goes. It could also be its own function, of course.

This is how I'm currently doing it (written with some old coworkers):

  def size_to_fill_with_hotspot(image, {crop_width, crop_height}, {hotspot_x, hotspot_y}) do
    image_width = Image.width(image)
    image_height = Image.height(image)

    ratio =
      if image_width > image_height do
        crop_height / image_height
      else
        crop_width / image_width
      end

    with {:ok, image} = Image.resize(image, ratio) do
      image_width = Image.width(image)
      image_height = Image.height(image)

      # Get the bounding Box
      point_x = image_width * hotspot_x - crop_width / 2
      point_y = image_height * hotspot_y - crop_height / 2

      # Make sure the bounding box isn't out of bounds
      point_x = max(point_x, 0)
      point_y = max(point_y, 0)

      point_x =
        if point_x + crop_width > image_width do
          image_width - crop_width
        else
          point_x
        end

      point_y =
        if point_y + crop_height > image_height do
          image_height - crop_height
        else
          point_y
        end

      Image.crop(image, round(point_x), round(point_y), crop_width, crop_height)
    end
  end

Anyway, that is all!

[kipcole9]

Andrew, very happy to accept a PR for this, it makes a lot of sense to me. And I want this library to be driven primarily by user requirement.If you can’t submit a PR I can work in this but it might take a week or so.Sent from my iPhoneOn 14 Jun 2023, at 04:11, Andrew Haust ***@***.***> wrote: Hey Kip! The Crop.crop_focus() option type lets us pass a one of a set of predetermined functions. At my work, we manually set a "hotspot" on each image for where we want the focus to be. Would you be interested in including this in Image? It's just a thought, I won't be offended if you won't 😅 I was thinking the API could be passing a "percentage point" to :crop. Image.thumbnail(image, "500x400", crop: {0.5, 0.5}) This would focus on the center of the image. I know that crop_focus options are sent wholesale to Vix so I'm not sure you'd ok with that inconsistency, but it seems like a good place for Image as far as discoverability goes. It could also be its own function, of course. This is how I'm currently doing it: def size_to_fill_with_hotspot(image, {crop_width, crop_height}, {hotspot_x, hotspot_y}) do image_width = Image.width(image) image_height = Image.height(image) ratio = if image_width > image_height do crop_height / image_height else crop_width / image_width end with {:ok, image} = Image.resize(image, ratio) do image_width = Image.width(image) image_height = Image.height(image) # Get the bounding Box point_x = image_width * hotspot_x - crop_width / 2 point_y = image_height * hotspot_y - crop_height / 2 # Check to see if the bounding box is going out of bounds point_x = if point_x < 0, do: 0, else: point_x point_y = if point_y < 0, do: 0, else: point_y point_x = if point_x + crop_width > image_width do image_width - crop_width else point_x end point_y = if point_y + crop_height > image_height do image_height - crop_height else point_y end Image.crop(image, round(point_x), round(point_y), crop_width, crop_height) end end I know I clean some parts up there and make use of thumbnail but this is actually old Ruby code ported to Elixir and I haven't bothered changing it yet. Anyway, that is all! —Reply to this email directly, view it on GitHub, or unsubscribe.You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[sodapopcan]

Great! I can do a PR, I was just posting code in case it triggered some immediate feedback. I can do this week.