Color not accurately preserved in exported PNG

[Former user]

1. The SVG below draws two boxes filled with similar but different shades of blue.

<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"> <rect x="10" y="10" height="80" width="80" style="stroke:#ff0000; fill: #4000c0"/> <rect x="110" y="10" height="80" width="80" style="stroke:#ff0000; fill: #4020c0"/> </svg>

2. Use Gapplin to export the image to PNG.

3. The two blue fill colors are identical in the PNG (as checked by Apple's Digital Color Meter in the Applications/Utilities folder).

(I'm no expert in the area of color spaces, so my apology in advance if this is a user error.)

[Ian Laird Campbell]

I had a similar problem. Below, the renderings on the left are gapplin exports to png and tiff, and on the right is gapplin viewer and a conversion from librsvg
brew install lbrsvg
rsvg-convert --format=png --output=libr.png mySVG.svg.

You can see that lbrsvg provides a much more similar output, though it also fails to capture colors exactly.

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