GIF animations only provide support for simple transparency, which can create unattractive edges around the graphic (where it meets the background). Since APNG tends to have a smaller file size and also has a better compression behavior than GIF, the quality advantage still holds.Ī further advantage: Animated PNG supports not only complete, but also partial (graded) transparency, which makes a natural integration of the animations into the existing web layout possible. Of course, it is important to keep in mind that a higher quality of the animated images always leads to a growing file size. The GIF format with its 8-bit support is limited to just 256 colors. The fact that APNG is a serious alternative to the established GIF is illustrated by a look at the properties of the Mozilla format: APNG supports a color depth of up to 24 bits and thus over 16 million colors. The respective number is also automatically assigned to the preceding fcTL block, so that the different frames can be brought back into the correct sequence at any time. Frame data chunk (fdAT): Frame data chunks are structurally equivalent to the standard PNG image data blocks (IDAT), but are additionally marked with a sequence number.It contains information, the most important of which is the display time of the frame. Frame control chunk (fcTL): The frame control chunk precedes each frame contained in the APNG animation.It shows the number of frames that make up the animation and also describes how often the animation should be played before it stops. Animation control chunk (acTL): This block informs the parser that the PNG is animated.However, the Animated Portable Network Graphics format includes three additional types of information blocks (chunks) that describe the animation and provide additional frame data. An application program that supports PNG (but not APNG) is still able to play an APNG file, but in this case, just a single image can be seen, not the complete animation.įrom a technical point of view, the APNG data stream largely corresponds to the standard PNG data stream whose structure can be found in the official image format specifications. You can see the page it is being used on here.Although APNG does not count as an official PNG extension, it is backward compatible to the basic format. I combined CSS animations with my Animated png and that allowed me to separate the circle behind and animate the image on top independently. The frame rates for animated pngs can be a lot smoother than my example, it was just a quick test consisting of 5 frames. A monstrosity I know and not the cleanest background removal but it was a fun test to play around with the animated png format. My Example Animated PNGīelow is what my test animated png looked like, ironically the preview is a gif. You can see the browser support for WebP here. You can make WebP images in the same online tool here so it is worth seeing the different between the two. This is a lot more overhead but you will make a huge file size saving using WebP on those browsers that support it, so it is worth considering. This will require you to use the picture tag to serve up multiple images formats. If you want to support all browsers with something like this, then you need to consider using the WebP format, then falling back to APNG for Safari/iOS users and finally having a static image fallback for browsers like Internet Explorer. Before rendering the files be sure to create a folder to save them in to because there will be a lot of files. Then you need to select your frame rate, you may need to tweak this to export the desired amount of frames. To do this, go to file > export > render video and choose ‘image sequence’ and set the alpha channel to ’Straight Unmatted’. ![]() So instead we need to export the frames individually. You can create your apng animation in Photoshop using the animation panel as you would a gif, but you will notice there is no option for apng export (this is available in Adobe Animate for those who use it). How to make apng files with transparent backgrounds These are a limitation in the gif format but apng offers much improved quality for transparency. ![]() You can see a list of browsers that support apng here.Īpart from file size, the main reason you would likely be forced to use apng is because of the jagged edges a transparent gif produces, in most cases these are unusable. The apng or animated png format improves on those areas, offering smaller file sizes, better colour depth, 24-bit transparency and support from all modern browsers with a static first frame fallback for those that don’t support it. The gif format has many uses and is still widely used but it does have some limitations.
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