: Using GIMP, given a black text on a white area having some grayish smudges, how do I remove everything except the text? Using GIMP, given a black text on a white area having some grayish

@Eichhorn212

Besides the method described by Lèse majesté (which, indeed, works just fine in GIMP), another useful noise removal tool to try, especially with JPEG compression noise like this, is Filters → Blur →
Selective Gaussian Blur. Here's what I got after applying it to your example image with the default settings (radius 5.0, threshold 50):


(Usually you'll have to play with the settings a bit to find the optimal values for your image. I was just lucky that the defaults worked pretty well even without any tuning.)

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@Murphy569

Don't know about GIMP, but in Photoshop you can just adjust the levels or curves so that the the grey smudges are hidden.

With levels you simply set the white point lower, at around 220 seems optimal.



Alternatively, you can adjust the RGB curve so that everything above 220 is output as 255 (white). This is similar to increasing the exposure to a photo. Then add a point at (105, 106) to anchor the lower tones to the baseline curve.



You can also play around with blurring the image slightly and then adjusting the curves/levels. By combining the blurred and unblurred version, you can get something like this:



Though personally I'd just recreate the image. It looks like it's done in Georgia bold or a similar font. It should take less time and get you much better results.

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