I produced a graph in matlab with a background color of R = 20, G = 33, and B = 43. I then saved that background as a PDF using export_fig (for some reason this process changed the background color a bit). Now I'm trying to match the background color of my poster to the one of the graph, but since the color changed in the export process, I no longer know the RGB values. I tried using the eyedropper tool on the PDF image, but the software says it bases the color measurement on a low resolution RGB version since it is a PDF, which ends up making the color applied to the background of the poster different from the one of the graph.
So I essentially need to accurately define the RGB values of the background of my graph.
Thank you for any help! If there is any confusion, I could email you my graph.
I no longer know the RGB values.
You can check the matlab color values in AcrobatPro via Print Production>Output Preview>Object Inspector. Here I've selected Object Inspector from the Preview popup and clicked on the object I want to sample.
I can see the profile is sRGB and the color values as percentages. To convert the percentages into ID's RGB values multiply them by 256 (for example the red channel would be .07800 x 256 = 20). Make sure the assigned RGB profile in your InDesign document is the same profile and plugin the RGB numbers for your RGB background color.
Do you have Acrobat Pro? If so, you can use the Output Preview to get your RGB values from the PDF.