One of challenges that face printers is dealing with substandard – for print application – art supplied by their customers. Sometimes, art that has been prepared for the web ends up in layouts intended for the press. Often, the graphics contain defects like jpeg compression artifacts or pixel noise in flat color areas. On the left is a supplied graphic at 100% and to it's right a small area enlarged to show the problem artifacts more clearly.
[Click on the image to open a larger version in a new window]The tool to get rid of the image artifacts while preserving the graphic detail is the "Smart Blur" filter in Adobe Photoshop. Below is its dialog box. You will need to experiment with the settings according to the specific image that you are working with. In general the "Radius" setting will be lower than the "Threshold" setting. The preview window shows the effect of changes you make to those settings. Sometimes, if the adjustments result in degrading the image, it's better to leave some artifacts and remove them afterwords using the clone or other tools. Always use the "High Quality" setting with "Mode: Normal."The final result – the artifacts in the graphic are cleared away while the detail of the text and art is preserved.
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