Dealing with many file format is a daunting task. Like for example, I always convert the video I get from Fraps from AVI to mp4 for lesser file size. Another example is converting JPGs to PNG or vice versa. My go to program with this stuff is Format Factory. It deals with images, videos and audio at the same time.
Here is the list of file formatting it can do.
Audio – All to MP3/WMA/AMR/OGG/AAC/WAV
Images – All to JPG/BMP/PNG/TIF/ICO/GIF/TGA
Videos – All to MP4/3GP/MPG/AVI/WMV/FLV/SWF
How To Use
Format factory is easy to use. You just need to click the file type you want to convert your existing file.
You can now click start after adding files. You can convert by batch easily by adding many files.