class.upload.php manages file uploads for you. It manages the uploaded file and allows you to do whatever you want with the file as many times as you want. If the file is an image, you can convert and resize it, rotate it, crop it in many ways. You can also add borders, frames, bevels, text labels, and watermarks or apply graphic filters such as unsharp mask, contrast or brightness correction, colorization, negative, greyscale, reflections, and more. Security features and file management functions are provided. Flash uploaders and XMLHttpRequest uploads are supported. The class can also work on local files, is useful for batch processing, and can circumvent open_basedir restrictions. Files can be output directly to the browser. The error messages are internationalized, and translations provided. It is compatible with PHP 4 and 5.
aria2 is a utility for downloading files. The supported protocols are HTTP(S), FTP, BitTorrent, and Metalink. It has a powerful segmented downloading ability, downloading a file from multiple sources and multiple protocols and utilizing your download bandwidth to the maximum. It supports downloading a file from HTTP(S)/FTP and BitTorrent at the same time, while the data downloaded from HTTP(S)/FTP is uploaded to the BitTorrent swarm. Using Metalink's chunk checksums, aria2 automatically validates chunks of data while downloading a file like BitTorrent.