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pro5:image_preprocessing

Image Pre-Processing

One of the key features of StudioLine is the ability to apply a complete set of image optimizations to an entire series of similar pictures. For proper image alignments, to crop unwanted borders, or to correct unappealing red pupil discolorations in people or animals (Red Eye Removal), use the appropriate tool from the “Preprocessing“ section of the “Image Toolbox” panel.

Crop and Rotate

If you simply need to change a photo from horizontal to vertical alignment (portrait vs. landscape) or vice versa, click the “Rotate Clockwise” or “Rotate Counter-Clockwise” button on the bottom toolbar. The Crop and Rotate selection in the Image Toolbox opens a window with more fine-tuning capabilities. Align the dotted line of the crop tool to a line in the image and rotate to the exact degree quickly and effortlessly. The “Crop and Rotate” tool performs a number of tasks:

  • Rotate
    If your camera has no orientation sensor, then you will likely need to rotates portrait images by 90°.
  • Mirror
    This can be helpful if a slide or transparency was scanned backwards.
  • Crop
    Use the cropping knife handles in the panel to trim off any scanning margins or to define a better composition.
  • Align
    If the camera was tilted or an image was not perfectly aligned in the scanner, you can place the alignment handles along a known vertical or horizontal line in the image.
  • Choose Aspect Ratio
    Enter the desired aspect ratio and then select the “Fix” checkbox. Now the horizontal and vertical cropping knife handles will always move together so that the resulting cut-out area will maintain the chosen aspect ratio.

Red-Eye Correction

An annoying result of flash photography is red pupil discoloration in people and other pupil colors in animals. To correct this effect use the “Red Eye Removal” preprocessing tool.

In the left “Select Area” pane, click on a discolored eye. The “Select Red Eye” pane on the right zooms into the selected area so that you can make an accurate selection. In the right pane, click exactly inside the discolored pupil.

StudioLine will correct the discoloration. If the result is not satisfactory, you can manually adjust the result:

The slider “Color Tolerance” expands or reduces the area that will be corrected, in case too much or too little of the pupil was effected.

The slider “Adjustment Effect” controls the intensity of the color correction.

Repeat these steps for as many eyes as necessary. Each corrected eye is tagged with a number. This way you can later pick individual eyes and make further corrections. To remove the correction for a particular eye, choose it with the “Eye No.” control and then click the “Delete” button next to it. To remove all red-eye corrections, drag the “Copy” button of this panel to the recycle bin.

ICC Color Profiles

ICC color profiles are based on a vendor-independent standard by the International Color Consortium and define distinct color spaces for individual devices, such as monitors and printers. This assures printed output will match the appearance on your monitor, assuming the devices support ICC color profiles. To manage the ICC color profile associated with an image, select the image and open the “ICC Color Profile” pre-processing tool from the image toolbox.

If there is already an associated color profile, it will be displayed. To assign a new color profile, open the drop-down list and choose the color profile for the device that recorded the original image – typically your digital camera or your scanner. (The drop-down list will only show color profiles for the RGB color space).

When images are loaded that have new ICC color profiles, then those profiles are added automatically to the “ICC Color Profile” list and can be used with other images.

You can set default color profiles to be associated with images that are loaded from specific sources. Choose from the Menu Bar: “Preferences” → “Image Archive” → “ICC Color Profile”.

The “Cameras” list includes all models found in the Exif descriptors anywhere in the Image Archive. From the “File Extension” list, choose a graphics file type used by the specific camera. From the “ICC Color Profile” list, choose the default color profile to be associated with the selected camera/file extension combination. You can use the “Add” button to import new ICC color profiles from disk or other media. Click the “Apply” button to save the default color profile association.

Resize Original

The size of digital images can be measured in two ways:

  • Pixel Size
    Pixel size (for example 1024 x 768 pixels) defines the number of color dots that comprise the image. A large number of pixels requires more storage space, but provides better resolution since more detail was recorded. Images with a large pixel size are suitable for high quality and large prints. An image with a small pixel size is good for emails and web sites, but nothing more.
  • Print Size
    The printed size of an image, measured in inches or cm, is a function of its pixel size and the printer resolution (for example 300 DPI). A high resolution printer prints pixels closer together, resulting in a smaller output. A lower resolution printer will print a larger print, since the number of pixels remains the same, only the distance between them changes. Best results are accomplished with an image that has a large pixel size printed on a high resolution printer.

For maximum flexibility, StudioLine will catalog images without changing the pixel size. During export or for sending emails, you can choose a pixel size to suit your needs (see chapters “Exporting” and “Sending Images via Email”). When printing, you can choose a suitable print size (see chapter “Printing – Custom Print”).

StudioLine does allow you to permanently reduce the pixel size of original images. This may be useful if you scanned an original in better resolution than you ever expect to need. You should keep in mind, however, that both print and internet technology keeps advancing with disk storage becoming increasingly affordable. In a few years you could find yourself scrambling for that original size, which may have seemed excessive today.

Preparing to Resize

Because resizing causes a loss of resolution, your final image will have superior quality if you first perform all other pre-processing tasks. From the Image Toolbox, choose “Crop and Rotate” to define the ideal cut-out area for your images. Choose “Red-Eye Removal” to correct any discolored pupils. Also, any touch-ups you may want to do are easier to perform before resizing and will look more convincing later. Only after these preliminary steps are complete, choose one or multiple images and click on “Resize Original” in the Image Toolbox. StudioLine opens the “Resize Original” window.

Similar to the “Export” window, you can save and recall frequently used settings.

Image Size

The “Image Size” drop-down menu offers a variety of options, including common standard sizes. The choice “Use Original Image Size” will retain the current size when using this window to convert between graphics formats instead (for example from TIFF to JPEG).

“Custom” activates the width and height controls to define any custom size. The standard or custom size you choose defines a bounding rectangle into which StudioLine will proportionally scale the images. Consequently, one side of the resized image (unless it’s a square) will be smaller than the chosen “Maximum Size”, if the selected width/height proportions do not match the image’s proportions. Enlarging images produces poor image quality and is therefore not recommended.

The option “Automatically Adapt to Orientation” keeps your portrait orientation images portrait, and your landscape orientation landscape. Let us say you specify an image size of 640×480 pixels, then a portrait orientation image will be 640 pixels high, whereas a landscape orientation image will be 640 pixels wide. The long side will always receive the larger amount of pixels. This saves a lot of extra steps and headaches.

Next to the image size input fields, you can choose the unit of measurement as pixels, inches, or centimeters. That is helpful if images are later emailed to be printed at a given paper size. The field “DPI” will let you control the print resolution.

Format

Near the bottom of the panel you select the file format. The default is “JPEG”, which uses a very effective compression algorithm to reduce file size while retaining optimum image quality. JPEG format gives you the further option to customize image quality and file size as you need it. The higher the quality, the more memory space the file will use. The lower the file size, the lower the image quality, the quicker the image will load on a web page or in an email.

Other file formats have a static image quality, equivalent to the original quality. These formats have high disk space requirements.

pro5/image_preprocessing.txt · Last modified: 2021/04/26 11:50 by 127.0.0.1