Transparent background in JPEG image

Question

How can I set a transparent background on JPEG image? This is a doubt of many colleagues of mine.

What would be the solution using Paint on Windows?

What are

Answer 1

If you’re concerned about the file size of a PNG, you can use an SVG mask to create a transparent JPEG. Here is an example I put together.

Answer 2

JPG does not support a transparent background, you can easily convert it to a PNG which does support a transparent background by opening it in near any photo editor and save it as a.PNG

Answer 3

JPEG can't support transparency because it uses RGB color space. If you want transparency use a format that supports alpha values. Example PNG is an image format that uses RGBA color space where (r = red, g = green, b = blue, a = alpha value). Alpha value is used as an opacity measure, 0% is fully transparent and 100% is completely opaque. pixel.

Answer 4

How can I set a transparent background on JPEG image?

If you intend to keep the image as a JPEG then you can't. As others have suggested, convert it to PNG and add an alpha channel.

Answer 5

Just wanted to add that GIF "transparency" is more like missing pixels. If you use GIF then you will see jagged edges where the background and the rest of the image meet. Using PNG, you can smoothly "composite" images together, which is what you really want. Plus PNG supports highly quality images.

Don't use "Paint". There are many high quality art applications for doing art work. I think even the cell phone apps (Pixlr is pretty good and free!) and web-based image editting apps are better. I use Gimp - free for all platforms.

While a JPEG can't be made transparent in and of itself, if your goal is to reduce the size of very large image areas for the web that need to contain transparent image areas, then there is a solution. It's a bit too complicated to post details, but Google it. Basically, you create your image with transparency and then split out the alpha channel (Gimp can do this easily) as a simple 8-bit greyscale PNG. Then you export the color data as a JPG. Now your web page uses a CANVAS tag to load the JPG as image data and applies the 8-bit greyscale PNG as the Canvas's alpha channel. The browser's Canvas does the work of making the image transparent. The JPEG stores the color info (better compressed than PNG) and the PNG is reduced to 8-bit alpha so its considerably smaller. I've saved a few hundred K per image using this technique. A few people have proposed file formats that embed PNG transparency info into a JPEG's extended information fields, but these proposal's don't have wide support as of yet.

Answer 6

You can't make a JPEG image transparent. You should use a format that allows transparency, like GIF or PNG.

Paint will open these files, but AFAIK it'll erase transparency if you edit the file. Use some other application like Paint.NET (it's free).

Edit: since other people have mentioned it: you can convert JPEG images into PNG, in any editor that's capable of working with both types.