+ unsigned char const * data = static_cast<unsigned char const *>(_blob.data());
+ if (data[801] == 1 || magick_image->image()->colorspace == Magick::sRGBColorspace) {
+ /* Either:
+ 1. The transfer characteristic in this file is "printing density"; in this case ImageMagick sets the colour space
+ to LogColorspace, or
+ 2. The file is sRGB.
+
+ Empirically we find that in these cases if we subsequently call colorSpace(Magick::RGBColorspace) the colours
+ are very wrong. To prevent this, set the image colour space to RGB to stop the ::colorSpace call below doing
+ anything. See #1123 and others.
+ */
+ magick_image->image()->colorspace = Magick::RGBColorspace;
+ }
+
+ magick_image->colorSpace(Magick::RGBColorspace);
+