Step one - work out what kind of file Tika thinks it is. You can either get that from the metadata if you're already passing it, or from the Tika App using the detect option
$ java -jar tika-app-1.5.jar --detect wireframe.pdf
application/pdf
Next up, you need to get the list of all the parsers that the Tika App version you're using knows about, along with the mime types that they handle:
$ java -jar tika-app-1.5.jar --list-parser-details | grep -B 2 -A 2 application/pdf
application/vnd.oasis.opendocument.chart
org.apache.tika.parser.pdf.PDFParser
application/pdf
org.apache.tika.parser.pkg.CompressorParser
application/x-bzip
From that, we see that a PDF file would be handled by org.apache.tika.parser.pdf.PDFParser
For your specific case of image/vnd.wap.wbmp
and Tika 1.5, we see that the parser being used is org.apache.tika.parser.image.ImageParser
(Note - all of this applies to using the Tika-App executable jar, where you can't change this. If you were using Tika from your own Java code you'd have more options available, but where you also have to make sure you include all the dependency jars for it to work properly!)