Picasa Web Albums

Picasa Web Albums (PWA) was an image hosting and sharing web service from Google, often compared to Flickr and similar sites. The service links with Google's photo organizing desktop program Picasa. It was discontinued in May 2016 and succeeded by Google Photos.

It allowed users with a Google account to store and share photos with an initial free storage offering of 15 GB, that is shared with Gmail and Google Drive. Storage was unlimited for photos of resolution less than 2048x2048 pixels for Google+ users, and for photos of resolution less than 800x800 for everyone else. Videos shorter than 15 minutes also don't count towards the limit. Once the storage is full, uploaded photos are automatically resized to fit the resolution for unlimited storage.

On February 12, 2016, Google announced that the service as well as the application will be discontinued on May 1, 2016 and March 15, 2016, respectively. Existing users of the application will still be able to use the application. Existing users of the service were advised to use Google Photos, which already stores the photos in Picasa Web Albums and is a new place for viewing, downloading and deleting (but not editing or organizing) the albums along with their meta-data will be created in the future.

Users may upload pictures through a variety of ways: via the PWA web interface on supported browsers, Picasa 2.5 or later on Microsoft Windows, using the Exporter for iPhoto, the Aperture to Picasa Web Albums plug-in, Uploader on Mac OS X,F-Spot on Linux, or through WAManager in the Amiga-like OS MorphOS. In both free and paid accounts, the actual resolution of the photo is maintained, even though a smaller resolution photo may be displayed by the web interface.

In Picasa 3 versions of the software, using the 'original size' upload option, pixel size remains the same, but JPEG compression is increased significantly during upload to PWA. As JPEG is a "lossy" format, some picture information (and quality) is lost. Picasa 3.6 added an option to preserve original JPEG quality.

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Wikipedia