The TIM format is associated with bitmap images used by some games designed for Sony Playstations. It's an uncompressed format and it is considered uncommon, so opening such files outside the software they were created for might be difficult.
The quick and simple way to handle your files is to get a quality piece of software, such as reaConverter. This software is extremely efficient in managing a wide range of batch conversions. As you will soon realize, reaConverter will help you avoid spending countless hours trying to figure out how to convert multiple TIM files as once.
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