make a photo of sheet music black and white, remove grey

[carljong]

I've been taking photos of sheet music and would like to print them.  But, when I print them the background is grey and I would like to make it white.

Is there a simple way to do that?

Thanks

[rich2005]

Make sure the image is in RGB mode Image -> Mode -> RGB
then try
Colors -> Auto -> White Balance

[carljong]

Tried it. Didn't do anything.

[Zero01]

If you have G'MIC try 'Repair > Clean Text'

[sallyanne]

(11-19-2021, 12:00 PM)carljong Wrote: I've been taking photos of sheet music and would like to print them.  But, when I print them the background is grey and I would like to make it white.

Is there a simple way to do that?

Thanks

Have you tried curves?

[rich2005]

(11-19-2021, 02:27 PM)carljong Wrote: Tried it.  Didn't do anything.

Well that is no help as a response.

Unlikely you will get g'mic plugin working with macOS 

If you can see this animation, it goes through the usual  https://i.imgur.com/5wNKaBW.mp4
auto - which does not work for you
Colors -> Levels and pick the white point
Use the Colors -> Curves

How are you taking the photos ? Mobile phone ? or camera ? Make a clip of part of the image and post it.

[Ofnuts]

(11-19-2021, 12:00 PM)carljong Wrote: I've been taking photos of sheet music and would like to print them.  But, when I print them the background is grey and I would like to make it white.

Is there a simple way to do that?

Thanks

The simplest way is adding some contrast in the Brightness/Contrast tool. You can also be lucky with Colors > Auto > Stretch contrast.


Otherwise please attach a sample image, so we what you are up against.

[david]

This is something I have been doing for many years.

I find the best solution is to use curves. Move the topmost point to the left until the background is white and move the bottom point too the right until the staves, notes and rests are clear - these are the most important! On well thumbed copies you may have to put up with the odd discoloured mark on the background in order to make sure the notes are readable.

This method has the advantage that it is fast. If you have only a few sheets to print you can of course use more sophisticated methods.

[carljong]

I'm taking photos with an iPhone Xr.

Thanks for all the responses. I will give them a try