Optimize to File Size: Ability to automatically select both the file format (JPEG or GIF) and JPEG compression level to achieve the selected file size.

优化文件大小：可以自动选择文件格式（jpeg或gif）和选择jpeg的压缩率，以实现选定的文件大小。

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Most other image compression systems, such as the widely used Jpeg format, are applied after an image has been snapped.

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The pictures can be exported into the standard JPEG format for use in other software, but then they lose their ability to be refocused.

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Although the Jpeg format later caught on because it is better at compressing photographs, Gif's technique remains superior at tackling images containing large areas of uniform colour when no more than 256 different colours are used in the whole picture.

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