Fix panic when prediction calculation is invalid (#282)

Author: richard-viney

.github/workflows/rust.yml

@@ -50,7 +50,7 @@ jobs:
       - name: Installing emulator and linker
         run: |
           sudo apt-get update
-          sudo apt-get install qemu binfmt-support qemu-user-static gcc-aarch64-linux-gnu binutils-aarch64-linux-gnu
+          sudo apt-get install qemu-system binfmt-support qemu-user-static gcc-aarch64-linux-gnu binutils-aarch64-linux-gnu
 
       - name: Installing Rust toolchain
         uses: actions-rs/toolchain@v1

src/parser.rs

@@ -405,6 +405,12 @@ pub fn parse_sos<R: Read>(reader: &mut R, frame: &FrameInfo) -> Result<ScanInfo>
     let predictor_selection;
     let point_transform = successive_approximation_low;
 
+    if point_transform >= frame.precision {
+        return Err(Error::Format(
+            "invalid point transform, must be less than the frame precision".to_owned(),
+        ));
+    }
+
     if frame.coding_process == CodingProcess::DctProgressive {
         predictor_selection = Predictor::NoPrediction;
         if spectral_selection_end > 63 || spectral_selection_start > spectral_selection_end ||