Graphics file formats transparency

There are a handful of SVG hosting options including svgur. But note that the more complex your SVG the larger the file will become.

Now that we have covered the differences between popular file formats it is time to see them side by side. This covers most logos and branding, icons, simple maps, charts, and diagrams. The original image is a Below you will be able to see the difference in compression size as well as image quality. For this image, assuming we have the original vector file, SVG is the obvious choice at 6kb.

In the photo above, the color remains preserved in all formats aside from banding and noise that stand out in the shadows of the hair, skin, and background as well as at the top of photo as seen in the GIF and PNG-8 outputs. Have a question about Photoshop? It can be transparent against any background despite being anti-aliased. However, support is even more patchy. Internet Explorer does not support partial transparency in a PNG graphic.

Very few applications correctly process TIFF files with alpha channels. See also monochrome or with shades of grey and anti-aliasing. The process of combining a partially transparent color with its background "compositing" is often ill-defined and the results may not be exactly the same in all cases. For example, where color correction is in use, should the colors be composited before or after color correction? This image shows the results of overlaying each of the above transparent PNG images on a background colour of A0.

Note the grey fringes on the letters of the middle image. An alternative approach to full transparency is to use a clipping path. A clipping path is simply a shape or outline, that is used in conjunction with the other graphics. Everything inside the path is visible, and everything outside the path is invisible. The path is inherently vector, but can potentially be used to mask both vector and bitmap data. The main usage of clipping paths is in PostScript files.

While some transparency specifications are vague, others may give mathematical details of how two colors are to be composited. This gives a fairly simple example of how compositing calculations can work, can produce the expected results, and can also produce surprises. In this example, two greyscale colors are to be composited. Greyscale values are considered to be numbers between 0.

To emphasise: this is only one possible rule for transparency. If working with transparency, check the rules in use for your situation.

Some consequences of this are:. This is important as it means that when combining three or more objects with this rule for transparency, the final color depends very much on the order of doing the calculations.

Although the formula is simple, it may not be ideal. Human perception of brightness is not linear - we do not necessarily consider that a grey value of 0. Such details may not matter when transparency is used only to soften edges, but in more complex designs this may be significant. Most people working seriously with transparency will need to see the results and may fiddle with the colors or where possible the algorithm to arrive at the results they need.

But it cannot be applied to all color models. For example Lab color would produce results that were surprising. An alternative model is that at every point in each element to be combined for transparency there is an associated color and opacity between 0 and 1. For each color channel, you might work with this model: if a channel with intensity and opacity overlays a channel with intensity and opacity the result will be a channel with intensity equal to , and opacity.

On top of that the PNG variant can be used for more complicated images with diverse tones — such as photos. The PNG variant supports full alpha transparency that will let you vary the degree of transparency. That can allow you to create transparency gradients and more complex types of transparency. One of the more recent formats to support transparency is WebP.

It is designed to cater to web-based images, and uses lossless and lossy compression to reduce the file size of image files significantly. However that it starting to change as both Firefox and Edge have announced upcoming support for WebP — and Chrome and Opera already support it. If you use a photo background editor to remove the background and make it transparent, you will need to save it in one of the formats listed above for it to continue to be transparent.

For example if you use Movavi Photo Editor you can choose between any of them. On top of that vector image formats support transparency as well, but are not the same as normal i. Suffice to say the three formats listed above should cater to your needs if you want to save an image with a transparent background. Now that you know their features and limitations, it should make it easier to decide on one. I am Catherine. This blog is my hobby as I love to read and write.

I could not decide weather to choose one topic for writing or to do it all. Finally I though to go all out and write and share whatever I feel like on a given day.