how to make a jpeg image semi transparent using gimp? [duplicate] - jpeg

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Closed 10 years ago.
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Image background transparent GIMP
I've a jpeg image. i'd like to make it more transparent as i'm using it in my android app as a background. It will have textview in front of it and the image's colours can clash with text in the views.
How can i increase transparency using GIMP?

A JPEG image can not support an alpha channel (transparency) and so you would need to use a file format that can. My recommendation would be .PNG

Related

why does gnome automatically fills the symbolic icons in files

I try to design some icons for gnome (symbolic icons) but the problem is that gnome files make them completely black(it fills the transparent areas in the icons)
how i can solve this problem
Use SVG or PNG for the image file of the icon.
https://specifications.freedesktop.org/icon-theme-spec/icon-theme-spec-latest.html
Some other image formats don't support transparent white space. I recommend testing your icons in an image viewer that supports white space. If you get a similar effect, mind this is not in the editing program so what your seeing in the image decoding library making sense of the image, then you should try to change image format to a different format that supports transparent white space. If you are using Gnome, Eye of Gnome, the default image viewer, should show a gray checkered pattern where there is white space.

SkiaSharp support for color quantization for PNG files

I'm looking for an all-in-one solution for processing web images
Resizing
Cropping
Save as WEBP / JPEG / PNG
Drawing simple rectangles
Adding text
Reducing colors (quantization) for PNG
The only thing I'm not clear about is PNG quantization. Currently I'm using pngquant which works great, but I'd prefer to do everything in one place.
I see the SkiaSharp has SKImage.Encode() which takes a quality parameter. However there's no explanation as to what it actually is. Will this give me color quantization for PNG files? If not, is there something else in the library to do this?

Font rendering in XNA is getting low quality

I am currently working in XNA 4.0 trying to render a font that I got. The font is rendered with this:
spriteBatch.DrawString(this.font, this.text, new Vector2(10, 10), this.color);
But some of my letters gets blurry and low quality (See image)
I have tried to change the SamplerState of the GraphicDevice but that does not seem to improve anything.
-Update-
After testing one of the ideas were XNA would compress the text and in that case loosing quality i tried out to create my own font texture instead of generating one using a .spritefont. And then sending that into the contentloader, the results I managed to get was just slightly larger text but with the same artifacts.
See Image
And I was now wondering if the problem still can have to do with compressing problems or if there could be another issue making the font get a lower quality in the program compared to using it ouside the program.
The way I am currently loading my font is using
font= ContentManager.Load<SpriteFont>(FontPath);
It's because XNA uses compression for spritefonts. The possible workarounds are:
Use Nuclex framework, which includes an alternative font importer;
Make your own font texture, following the instructions from Shawn Hargreaves's blog;
In your SpriteFont definition, double the size of generated font, then draw it at half its size.

How to display a .bmp in an NSImageView for MacOs so that a certain color is transparent?

I have some .bmp files that have some color (maybe black) that is supposed to show as transparent when the graphic is displayed on top a form, so the form color comes through the transparent areas. But by default, when I put these images in an Image View, the black/transparent areas show up as BLACK!
I'm thinking I need to either:
- alter how the NSImageView shows the image, so that a certain color is transparent, or
- modify the .bmp files somehow to make that color suitable for transparency in an NSImageView
But I don't know enough about graphics files, transparency(alpha), NSImageView, nor the image editing tools. I'm trying to use Gimp, but...not sure what I'm doing yet. It seems like there is already a color that should be transparent in the current .bmp file.
I'm sure its something simple for setting NSImageView, or editing my file, or perhaps making a mask for the image, but I don't know how yet. I've looked at various filters in IB for NSImageView, but have not found where to set the transparent color, nor how to grab that color from the image file to make sure I use the correct value.
Thanks in advance for any assistance. (I tried to post some images, but because I'm new, I could not.)
Beau
I'm not a Cocoa developer, but in Gimp try adding an alpha channel to your image (a layer mask, perhaps) then saving as a 32-bit PNG image (with an alpha channel), then load that PNG directly into your NSImageView. If you want to make the black pixels transparent in Gimp use the magic-wand tool to select them (use magic-wand with 0 tolerance) and just delete the contents of the selection then save as a PNG directly.

Pixlelated borders when i save image as GIF with Transparent In Illustrator

World Map Images in Adobe Illustrator CS5
I have an image Map in illustrator CS5 which i want to save in GIF so as to reduce its size for web use. But when i save it, the map boundaries are having some white pixels all along the map boundaries of map.
I really dont know why has happened to it, but cant save it in Png-8, png-24 formate due to size constraint.
Any meaningful answer will be highly appreciate and thanks in advance.
Is your background a non-changable color? Maybe you can save the image with the same color as a background.
The problem is gifs don't support true transparency.
If this doesn't work can you provide the image you are trying to save (gif and png, I don't have AI right now)? Maybe there will be something I can do about the size or clearing the gif's edges.
transparent GIFs don't have an 8-bit alpha channel, like PNG does: a pixel in a GIF is either there, or it's not: if it's there, you can't see through it. This often means that an edge between transparent and non-transparent areas looks blocky.
There are two ways to deal with this... either use a PNG 24 (and the Illustrator Save for Web feature will help you to make it smaller), or in Illustrator create a background color layer behind your image before you export to GIF. If this background color layer is the same as the website you put the image on, the edges will blend nicely.

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