Minor improvements to EXR decoding. (#177)

See also #176.

This closes #166.

libs/imageio/src/ImageDecoder.cpp

@@ -576,11 +576,13 @@ LinearImage EXRDecoder::decode() {
         int ret = LoadEXRFromMemory(&rgba, &width, &height, src.data(), src.size(), &error);
         if (ret != TINYEXR_SUCCESS) {
             std::cerr << "Could not decode OpenEXR: " << error << std::endl;
+            FreeEXRErrorMessage(error);
             mStream.seekg(mStreamStartPos);
             return LinearImage();
         }
 
-        src.resize(0);
+        src.clear();
+        src.shrink_to_fit();
 
         LinearImage image(width, height, 3);
 
@@ -596,6 +598,8 @@ LinearImage EXRDecoder::decode() {
             }
         }
 
+        free(rgba);
+
         return image;
     } catch(std::runtime_error& e) {
         // reset the stream, like we found it