The BMX image format is associated with Siemens mobile phone animations. In case you found such a file it was probably created a long time ago, as Siemens mobile phone division was sold to BenQ in 2005 and such files are no longer supported. Opening a BMX image may require conversion to a more accessible format.
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 BMX files as once.
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