Jonathan D Posted November 3, 2019 Share Posted November 3, 2019 I have got a number of picture border files in JPG format I need to convert to transparency in PNG format. I need pure black to become fully opaque, pure white to become 100% transparent and various shades of grey to become various amounts of transparency. Some of the files are just pure black and pure white. These are easy to convert: Flood select tool on the white, press delete and instant 100% transparency, then export. It's the various shades of grey I am struggling with. Any help gratefully received. Jonathan Quote Link to comment Share on other sites More sharing options...
Greyfox Posted November 4, 2019 Share Posted November 4, 2019 14 hours ago, Jonathan D said: I need pure black to become fully opaque, pure white to become 100% transparent and various shades of grey to become various amounts of transparency. Perhaps see if this post helps Jonathan D 1 Quote Intel i7-10700 Gen10 CPU, 32GB RAM, Geforce GTX 1660 OC 6GB Windows 10 Pro 22H2, 1x 1TB M.2 NVMe, 1 x 2TB M.2 NVMe. Affinity APh, APu, ADe Link to comment Share on other sites More sharing options...
walt.farrell Posted November 4, 2019 Share Posted November 4, 2019 On 11/3/2019 at 6:05 AM, Jonathan D said: I need pure black to become fully opaque, pure white to become 100% transparent and various shades of grey to become various amounts of transparency. If you're using Affinity Photo, you might try the following: Have your image at the bottom of the layer stack, and make sure it's a (Pixel) layer (rasterize it if it isn't). Place a pure black Fill layer below your image. Click on the image in the Layers panel, and invert it (Ctrl/Cmd+I (Windows/Mac)). Right-click on the image in the Layers panel and Rasterize to Mask. Optional: Then drag it to the mask position of the fill layer, or right-click and Mask to Below. Jonathan D 1 Quote -- Walt Designer, Photo, and Publisher V1 and V2 at latest retail and beta releases PC: Desktop: Windows 11 Pro, version 23H2, 64GB memory, AMD Ryzen 9 5900 12-Core @ 3.00 GHz, NVIDIA GeForce RTX 3090 Laptop: Windows 11 Pro, version 23H2, 32GB memory, Intel Core i7-10750H @ 2.60GHz, Intel UHD Graphics Comet Lake GT2 and NVIDIA GeForce RTX 3070 Laptop GPU. iPad: iPad Pro M1, 12.9": iPadOS 17.4.1, Apple Pencil 2, Magic Keyboard Mac: 2023 M2 MacBook Air 15", 16GB memory, macOS Sonoma 14.4.1 Link to comment Share on other sites More sharing options...
v_kyr Posted November 4, 2019 Share Posted November 4, 2019 See ... Greyscale to Transparency : how to ? Converting grayscale shades into alpha channel For bulk processing (many images) a tool like ImageMagick might be handy here, assuming an image is a greyscale PNG file then ... Quote convert greyscale.png -alpha off -alpha copy -type truecolormatte PNG32:greyscale_alpha.png ... see for ImageMagick and the control of image transparency this here. Jonathan D 1 Quote ☛ Affinity Designer 1.10.8 ◆ Affinity Photo 1.10.8 ◆ Affinity Publisher 1.10.8 ◆ OSX El Capitan ☛ Affinity V2.3 apps ◆ MacOS Sonoma 14.2 ◆ iPad OS 17.2 Link to comment Share on other sites More sharing options...
thriva Posted September 12, 2021 Share Posted September 12, 2021 Walt.farrell, you're a star. I have been looking all over for the answer to this question. Many thanks! Quote Link to comment Share on other sites More sharing options...
walt.farrell Posted September 12, 2021 Share Posted September 12, 2021 Glad to have helped, @thriva, and welcome to the forums. Quote -- Walt Designer, Photo, and Publisher V1 and V2 at latest retail and beta releases PC: Desktop: Windows 11 Pro, version 23H2, 64GB memory, AMD Ryzen 9 5900 12-Core @ 3.00 GHz, NVIDIA GeForce RTX 3090 Laptop: Windows 11 Pro, version 23H2, 32GB memory, Intel Core i7-10750H @ 2.60GHz, Intel UHD Graphics Comet Lake GT2 and NVIDIA GeForce RTX 3070 Laptop GPU. iPad: iPad Pro M1, 12.9": iPadOS 17.4.1, Apple Pencil 2, Magic Keyboard Mac: 2023 M2 MacBook Air 15", 16GB memory, macOS Sonoma 14.4.1 Link to comment Share on other sites More sharing options...
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