NConvert is a software that can batch convert over 400 types of image files.
NConvert is a cross-platform software that runs on the Linux, FreeBSD, OpenBSD, NetBSD, Solaris, AIX, Irix mips, HP-UX and Windows platforms.
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Here are some key features of "NConvert":
· Import about 400 graphic file formats
· Export about 40 graphic file formats
· Multipage TIFF, Animated GIF, Animated ICO support
· Resize
· Adjust brightness, contrast...
· Modify number of colors
· Apply filters (blur, average, emboss, ...)
· Apply effects (lens, wave, ...)
· And many many other things.