4.4. Paso alto

4.4. Paso alto
	4. Filtros de realzar

4.4.1. Generalidades

In sound processing, a high-pass filter filters high frequencies above a threshold. In digital images, frequency refers to sudden changes in brightness or color in neighboring pixels. The High Pass filter filters high essential details, and larger scale gradients are removed. This result, combined with the original image and "Soft Light" or "Hard Light" merge mode, is used to sharpen images. It enhances fine details.

4.4.2. Activar el filtro

You can find this filter through Filters → Enhance → High Pass….

4.4.3. Opciones

Figura 17.33. “High Pass” filter options

Presets, Preview, Split view: These options are common to GEGL-based filters. Please refer to Sección 2, “Características comunes”.
Desv. Est.: Increasing this Standard Deviation lowers the filter threshold and more image details are taken in account for treatment.
Contraste: Increase/Decrease contrast of treated details.
Recortado: El resultado de aplicar este filtro puede ser una imagen más grande que la original. Con la opción predeterminada Ajustar la capa se redimensionará automáticamente cuanto se necesite cuando se aplique el filtro. Con la opción Recortar el resultado se recortará a los límites de la capa.

4.4.4. Using High Pass Filter

Procedimiento 17.1. Enfocando

Open your image:
Duplicate layer:

This duplicate layer becomes the active layer.
Open High Pass filter.
Change mode to soft-light (try Hard-light also).
Settings and on-canvas view