The jpeg-decoder project has a new version with a number of improvements plus a fix for a possible panic. Semantic versioning considers 0.2.4 to be incompatible with 0.3.X because of the leading zero, so this change bumps the pin to 0.3.0.
The JPEG decoder may fail and panic the TIFF decoder. This commit converts the JPEG `Format(String)` error to a TIFF `Format(String)` error. Fixes #168