Hello, to complete my workflow, I would like to integrate Qimage One software with Affinity Photo for printing. I contacted the programmer (Andrew WILFORD of BINARTEM) of the software who told me that you sent me an API request, you did not answer him. As a user of Affinity software, it would be.

QImage also provides the static fromData function, constructing a QImage from the given data. When loading an image, the file name can either refer to an actual file on disk or to one of the application's embedded resources.
Reading and Writing Image Files¶. QImage provides several ways of loading an image file: The file can be loaded when constructing the QImage object, or by using the load or loadFromData functions later on. QImage also provides the static fromData function, constructing a QImage from the given data. When loading an image, the file name can either refer to an actual file on disk or to one.

Making fine prints in your digital darkroom
Pixels, images, and files
by Norman Koren

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Making fine prints in your digital darkroom
Understanding image sharpness and MTF
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Photographic technique
Image editing with Picture Window Pro

A simplified zone system
Digital vs. film

updated Oct. 19, 2004

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*Table of contents* *for the Making Fine* *Prints series*	Getting started Light & color \| Scanners Pixels, images, & files Pixels and images \| Image resolution How many pixels for s sharp print? Image file formats Digital cameras \| Printers \| Papers and inks Monitor calibration and gamma Printer calibration \| Scanning \| Basic image editing	Black & White \| Matting and framing Tonal quality and dynamic range in digital cameras Sacm 1935 a serial number. Color Management: Introduction \| Implementation Profiles with MonacoEZcolor \| Evaluating profiles

*for Image editing with* *Picture Window Pro*	Introduction \| Making masks Contrast masking	Tinting and hand coloring B&W images Example: Sunset, Providence, Rhode Island

This pages introduces the fundamental concepts of digital images: what they are, how their size and resolution is specified, and how they are stored.

Related pages:

Making fine prints.. Getting started | Photo printers | Scanners

Pixels and images

A digital image is a rectangular grid of pixels, or 'picture elements,' illustrated by the image on the right, which consists of 52x35 pixels; 1820 total. It has been enlarged 5x (to 260x175 pixels) to make the pixels visible. Pixels appear as squares when enlarged in this way.

Digital images exist as an array of bytes in a computer's RAM memory or as files in memory cards, hard drives, and CDs or DVDs. Several popular file formats are described below.

Each pixel typically consists of 8 bits (1 byte) for a Black and White (B&W) image or 24 bits (3 bytes) for a color image-- one byte each for Red, Green, and Blue. 8 bits represents 2⁸ = 256 tonal levels (0-255). 16-bit B&W and 48-bit color image formats are also available; each pixel represents 2¹⁶ = 65,536 tonal levels. Editing images in 16/48-bits produces the highest quality results; you can save images in 8/24 bits after editing is complete. An image's resolution is the total number of pixels, e.g., 1600 x2000 = 3.2 Megapixels, which corresponds to 3.2 Megabytes inside your computer for 8-bit B&W images or 9.6 Megabytes for 24-bit (3 bytes/pixel) color images. There are several other definitions of 'resolution.' See the explanation below.

Digital images are obtained from digital cameras or by scanning film or prints. Scanners are specified by their dpi or ppi resolution-- dots (actually, pixels) per inch they can obtain from the source. Scanning the original source-- the negative or slide-- always produces better quality than scanning a print. Printers are specified by their dpi (dots per inch) 'resolution,' typically 720, 1440 or 2880 for Epson. This number is the stepper motor pitch, not the actual visual resolution. It typically requires several printer dots to represent one image pixel. You don't need to worry about the correspondence between image pixels and printer dots; this is handled by the image editor and printer driver software.

Image resolution and print size

Considerable confusion arises because image size is specified by the number of pixels, the 'resolution' in dots or pixels per inch (dpi or ppi), and the physical size (width and height). But the only attribute that counts is the number of pixels.

The image on the left was taken on the Canon EOS-10D, converted from RAW using the Canon File Viewer Utility (which I've since replaced with Capture One DSLR LE), adjusted for color (though far from finished), then resized to 260x175 pixels wide in my favorite image editor, Picture Window Pro.

. The dialog box used to resize the image in is shown on the right. The original (Current) image is 3072 pixels wide