graphicsmagick:coder_MAT_fuzzer: Use-of-uninitialized-value in IsGrayImage

Detailed Report: https://oss-fuzz.com/testcase?key=5979093489811456 Project: graphicsmagick Fuzzing Engine: libFuzzer Fuzz Target: coderMATfuzzer Job Type: libfuzzermsangraphicsmagick Platform Id: linux Crash Type: Use-of-uninitialized-value Crash Address: Crash State: IsGrayImage WriteMATLABImag...