Handle channel value with new image in Image#opaque_channel with ImageMagick 7
Fix
@@ -9851,9 +9851,9 @@ Image_negate_channel(int argc, VALUE *argv, VALUE self)
#if defined(IMAGEMAGICK_7)
exception = AcquireExceptionInfo();
- BEGIN_CHANNEL_MASK(image, channels);
+ BEGIN_CHANNEL_MASK(new_image, channels);
(void) NegateImage(new_image, grayscale, exception);
- END_CHANNEL_MASK(image);
+ END_CHANNEL_MASK(new_image);
rm_check_exception(exception, new_image, DestroyOnError);
(void) DestroyExceptionInfo(exception);
#else
