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Metin Seven

Remove Black / White Matte

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Hi,

Photoshop offers a few functions to remove white or black outer edges of an image surrounded by transparency. It can be found in Layer ➔ Matting ➔ Remove Black Matte or Remove White Matte.

The functions are also very useful to fix semi-transparent shadows that were rendered against a white or black background. It removes the white or black sheen from the semi-transparent shadows, making the shadows and rim pixels ready to be placed on any kind of background color or image.

I really miss these options in Affinity Photo, and would be very happy to see them implemented.

Many thanks in advance,

Metin

— EDIT: See this post for a solution.


visualization • illustration • animation • 3D design — metinseven.nl

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@Metin Seven, that doesn't seem to do what I want it to. Take the following screenshot, for example (the image itself doesn't include the border you see here):

1345091023_ScreenShot2018-09-06at14_38_23.thumb.png.7bd6da3b3ed0f383f4cfd017f75b9801.png

Gimp's autocrop will collapse the image's borders towards the centre as long as there is no colour change, thus yielding the following result:

cropped.thumb.png.45f139b2f3baf6038429ddbf5bb57a47.png

This is what I was referring to. :)

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Do we have something similar in Affinity Photo...?

 

I have some 3D renders that I created in Cinema 4D. I have an object mask/channel (created in Cinema) to cut it out.

I want to save the render with transparency so they can change the background color easily, but I have a little color fringe in the borders. 

 

With Photoshop I can use the "defringe" or "remove white matte" option from the Matting menu and fix it with one click.

In Affinity Photo i tried using the defringe filter but it's not working, I guess it's not the same definition.

Is there a similar tool we can use in Affinity Photo?

 

Thanks

 

menu.png

render.png


------------------------

Fernando Velarde

www.velarde.com

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Filters > Colours > Erase White Paper

For Black you can invert the image first, the erase, then invert again.

Filters > Colours > Defringe will help get rid of edge pixels.

Flood Select Tool can also be used to get rid of solid coloured backgrounds (untick Contiguous to also select holes in the object).


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I've tried Erase White Paper on an image with a transparent background, but the filter also makes opaque parts semi-transparent. It's not the same as Photoshop's Remove White / Black Matte, which only removes the white or black residue in anti-aliased edges and the transparent part(s) of an image — such as semi-transparent shadows on a transparent background — effectively preparing it to be overlaid on any other color. That's what I really miss in Affinity Photo.


visualization • illustration • animation • 3D design — metinseven.nl

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Thank you for the suggestion Aammppaa.

 

I tried these but in this case the erase white paper doesn't help since my 3D render is not created with an all white background. It's part of a complicated render.

I have an alpha mask/buffer which is created in the 3d package and helps me isolate the object.

The problem is that little extra color fringe that I get when I extract the selection.... It need to be very precise because of the Ambient oclussion drop shadow I have. 

 

Deffinitetly like Metin comments we don't seem to have a similar Remove White/Black matte in A Photo...  

I can manually blur the edges a little bit and that helps.. but Just wanted to see if there was another solution I was missing .

 

thanks


------------------------

Fernando Velarde

www.velarde.com

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I also need something like this, if I'm understanding properly. I'm creating graphics for print on T-shirts. The customer chooses the color of the shirt online. They might pick a dark shirt or a light one, and yet the print has to look nice on it either way.

The direct-to-garment printer prints semi-transparent pixels on a white matte, so these designs will have glowing edges on a dark shirt unless I get rid of the semi-transparent pixels.

I found a way to accomplish this pretty easily for the black color. Fortunately, many of my drawings are outlined in black, making this easy for these cases. The procedure:

  1. Rasterize the document.
  2. Select the "Flood Select Tool" (aka magic wand). Set tolerance to 99%. (Uncheck "contiguous" if I can get away with it.)
  3. Click on a transparent pixel.
  4. Select | Grow by 1 pixel.
  5. Filter | Colors | Monochrome Dither.

Now I need a procedure for semi-transparent pixels in other colors.

 

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Hi guys,

I discovered an older topic about this, offering a solution by user @>|< , involving equations in Filters ➔ Apply Image, see this image:

Affinity Photo remove matte.png

It'd be great if the Affinity developers could turn this procedure into a one-click solution, or even better: a non-destructive adjustment.


visualization • illustration • animation • 3D design — metinseven.nl

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Imo  it's  just better to render anything against black background to exr output file.     With a special shadow catcher material for shadows.    Usually  3d soft allow to render "layers", a  special   set of objects  on a black background whatever actual background is.    And also capable to output un-premultipled  by alpha result  so you wouldn't have any black halo at  all.   

Or you   could just divide 32 bit floating point exr alpha channel to premultiplied render  getting same un-premultiplied result .          

And I even don't mention deep pixel exr and cryptomatte modern 3d soft doing.         So having done it in 3d soft properly   would make you never using that matte thing

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