Free Image Convert and Resize is the tool you need to convert an image into other formats and to resize its size to match your needs. It can process multiple images simultaneously and each of them can have its own parameters (size, resolution, etc.). Regarding the size, it allows you to have an accurate measure in pixel or in percentage by typing the data. The converted or resized image can be renamed. When doing so, you can customize their new names by adding a prefix, a suffix, by using a upper case for the first letter or by replacing a word. This software is free and supports JPG, PNG, BMP, GIF, TGA as well as PDF (export only).