Invalid colors for CMYK images when cmykProfile.jar missing in classpath

When rendering or optimizing images with a CMYK color space (DeviceCMYK), Qoppa’s PDF libraries and components need the cmykProfile.jar to be present in the classpath. If you forget to include this jar, you will get images with “weird” colors. Faces for instance will show with more intense, bright saturated colors (such as red and blue) […]

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Export PDF to PNG Image with Overprint Simulation

This Java sample below shows how to use Qoppa’s jPDFImages (or jPDFProcess) to load a PDF and export it to an image in PNG format with overprint simulation on. First, the image is rendered in CMYK profile, then converted to RGB using ColorConvertOp and finally saved as PNG (or JPEG). The resolution is set at […]

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Export PDF Page as Image using CMYK or Custom Color Space

In version v2105R1, a new feature was added to our PDF to Image Conversion Library, jPDFImages,  that allows rendering a page in a PDF document to CMYK color space or to any custom color space. Previous versions of the library would only render to the RGB color space which is typical when rendering to a […]

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Rendering to CMYK and Overprint Simulation

In version v2015R1, Overprint simulation was added to Qoppa’s Java PDF component jPDFEditor. This advance PDF technique is used by professionals in the print and pre-press industry. Overprint simulation allows to preview how two distinct colors that overlap will mix when printed.   RGB Rendering By default, Qoppa renders to RGB: To render to CMYK […]

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Optimizing images in a PDF document: compression, color space and resolution

Qoppa’s 100% Java PDF optimizer library, jPDFOptimizer, allows, among other things, to change the properties of images in a PDF document including the compression, the color space, and the DPI resolution. This is done using the ImageHandler interface and implementing the convertImage() method which allows an application to define optimization option per image or per […]

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