Download a google doc with animated gifs

So without scroll events, we've lost the ability to perform layout-related calculations on the headers. Instead of scroll events, we're going to use an IntersectionObserver to determine when headers enter and exit sticky mode.

Adding two nodes aka sentinels in each sticky section , one at the top and one at the bottom, will act as waypoints for figuring out scroll position. As these markers enter and leave the container, their visibility changes and Intersection Observer fires a callback.

The sentinels are positioned at the top and bottom of each section. Intersection Observers asynchronously observe changes in the intersection of a target element and the document viewport or a parent container.

In our case, we're observe intersections with a parent container. The magic sauce is IntersectionObserver.

Each sentinel gets an IntersectionObserver to observer its intersection visibility within the scroll container. When a sentinel scrolls into the visible viewport, we know a header become fixed or stopped being sticky. Likewise, when a sentinel exits the viewport.

Then, I added an observer to fire when. The observeHeaders function creates the top sentinels and adds them to each section. The observer calculates the intersection of the sentinel with top of the container and decides if it's entering or leaving the viewport. That information determines if the section header is sticking or not. The observer is configured with threshold: [0] so its callback fires as soon as the sentinel becomes visible. The process is similar for the bottom sentinel. A second observer is created to fire when the footers pass through the bottom of the scrolling container.

The observeFooters function creates the sentinel nodes and attaches them to each section. The observer calculates the intersection of the sentinel with bottom of the container and decides if it's entering or leaving. You can add more images from your computer or add image URLs. The queue is being uploaded, it should take just a few seconds to complete. Upload complete. You can create a new album with the content just uploaded. You must create an account or sign in to save this content into your account.

No image have been uploaded. Some errors have occured and the system couldn't process your request. Uploading or cancel cancel remaining. Note: Some images couldn't be uploaded. With WebP in open source, anyone can work with the format and suggest improvements. With your input and suggestions, we believe that WebP will become even more useful as a graphic format over time. You can use the WebP command line utility to convert your personal image files to WebP format.

See Using WebP for more details. If you have many images to convert you can use your platform's shell to simplify the operation. For example, to convert all jpeg files in a folder try the following:. Currently, you can view WebP files by converting them into a common format that uses lossless compression, such as PNG, and then view the PNG files in any browser or image viewer. To get a quick idea of WebP quality, see the Gallery on this site for side-by-side photo comparisons.

The converter code is available on the downloads section of the WebP open-source project page. The code for the lightweight decoder and the VP8 specification are on the WebM site. WebP is bitstream-compatible with VP8 and uses 14 bits for width and height. The maximum pixel dimensions of a WebP image is x See the WebP Lossless Bitstream specification. Yes, usually when converting from a lossy format to WebP lossless or vice versa.

This is likely to put too much pressure on the CPU and memory of the decoding client as each refresh event involves a full pass through the decompression system. On average, decoding a progressive JPEG image is equivalent to decoding the baseline one 3 times. Alternatively, WebP offers incremental decoding, where all available incoming bytes of the bitstream are used to try and produce a displayable sample row as soon as possible.

This both saves memory, CPU and re-paint effort on the client while providing visual cues about the download status. Build your project. Use System. Note that the library can be built manually with ndk-build and the included Android. Some of the steps described above can be reused in that case.

These functions can then be imported in C. Add libwebp. WebP supports both lossy and lossless compression; in fact, a single animation can combine lossy and lossless frames. GIF only supports lossless compression.

WebP's lossy compression techniques are well-suited to animated images created from real-world videos, an increasingly popular source of animated images. WebP requires fewer bytes than GIF 1. This is especially important on mobile networks. WebP takes less time to decode in the presence of seeking.

In Blink , scrolling or changing tabs can hide and show images, resulting in animations being paused and then skipped forward to a different point. Excessive CPU usage that results in animations dropping frames can also require the decoder to seek forward in the animation. In these scenarios, animated WebP takes 0.