Welcome to horo.ch

Functions of the Image menu that have not been covered yet are briefly presented here.

		• Raytracing •
< Raytracing < IBL and HDRI > Intro > Overview > Fisheye > Mirror Ball > Cube > Light • Filter > Plugins > Plugin Filter		— IBL and HDRI: HDRShop, Filter — Filter and other Funktions Functions of the Image menu that have not been covered yet are briefly presented here. Image > Transform > Rotate 90°: rotates the picture clockwise by 90°. Rotate 180°: rotates the picture until it is upside down. Rotate 270°: rotates the picture clockwise by 270° which is the same as rotating it counter clockwise by 90°. Flip H: flips picture horizontally, swaps left and right (mirror). Fliv V: flips picture vertically (upside down). DCT: Discrete Cosine Transform. Divides picture into squares 8 pixels wide and transforms these tiles into the frequency domain. IDCT: Inverse DCT. A use for DCT and IDCT has not yet crossed my mind (except that DCT comes in the JPEC compression algorithm after the conversion into the brightness-colourness-model and the colour subsampling, before the quantization of the DCT coefficients and the coding thereof). Size > Half Size: reduces the picture to half its size. Double Size: doubles the size of the picture. Half Size X: halves the width of the picture without touching its height. Half Size Y: halves the hight of the picture without touching its width. Arbitrary Resize…: opens a dialog. The current picture size is displayed in the fields Width and Height. Values may be changed and picture will be resized accordingly. Filter > Identity: no action or effect detected. Gaussian Blur…: opens a dialog to enter the Blur Width in pixels. X Derivate: appears to have a similar effect as a contour filter with a horizontal convolution mask after Prewitt. Y Derivate: appears to have a similar effect as a contour filter with a vertical convolution mask after Prewitt. De-Interlace: probably a filter to de-interlace the lines in a picture taken with a TV camera. Horizontal Motion Blur…: opens a dialog to enter the Blur Width in pixels. Neighbor Average: blur filter, has a similar effect as a convolving low pass filter with a mask that has all fields set to 1. A smoothing filter. Gradient: detects the sharp transitions and emphasises these as contours. Corner Detect: finds the corners in an image and emphasises them as contours. Small Circle Blur: another smoothing filter. Effects > Vignette: simulates the vignetting of a lens. Opens a dialog to enter the Inner and the Outer Radius. Randomize: fills a picture with random pixel values. Sepia tone…: opens the colour picker dialog. Converts to a monochrome picture with the colour selected. If white is selected, a black-and-white picture is produced. Quantize: seems to set the highest pixel value to 1. Signed Quantize: negative pixel values may emerge. DXC9000 Curve: adaption to the response curve of the 1/2" 3 CCD Progressive Scan Video Camera by Sony. (Professional studio video camers, price about $ 6,500.)
	© 2004 - 2018 by Horo Wernli.

Transform >
- Rotate 90°: rotates the picture clockwise by 90°.
- Rotate 180°: rotates the picture until it is upside down.
- Rotate 270°: rotates the picture clockwise by 270° which is the same as rotating it counter clockwise by 90°.
- Flip H: flips picture horizontally, swaps left and right (mirror).
- Fliv V: flips picture vertically (upside down).
- DCT: Discrete Cosine Transform. Divides picture into squares 8 pixels wide and transforms these tiles into the frequency domain.
- IDCT: Inverse DCT. A use for DCT and IDCT has not yet crossed my mind (except that DCT comes in the JPEC compression algorithm after the conversion into the brightness-colourness-model and the colour subsampling, before the quantization of the DCT coefficients and the coding thereof).
Size >
- Half Size: reduces the picture to half its size.
- Double Size: doubles the size of the picture.
- Half Size X: halves the width of the picture without touching its height.
- Half Size Y: halves the hight of the picture without touching its width.
- Arbitrary Resize…: opens a dialog. The current picture size is displayed in the fields Width and Height. Values may be changed and picture will be resized accordingly.
Filter >
- Identity: no action or effect detected.
- Gaussian Blur…: opens a dialog to enter the Blur Width in pixels.
- X Derivate: appears to have a similar effect as a contour filter with a horizontal convolution mask after Prewitt.
- Y Derivate: appears to have a similar effect as a contour filter with a vertical convolution mask after Prewitt.
- De-Interlace: probably a filter to de-interlace the lines in a picture taken with a TV camera.
- Horizontal Motion Blur…: opens a dialog to enter the Blur Width in pixels.
- Neighbor Average: blur filter, has a similar effect as a convolving low pass filter with a mask that has all fields set to 1. A smoothing filter.
- Gradient: detects the sharp transitions and emphasises these as contours.
- Corner Detect: finds the corners in an image and emphasises them as contours.
- Small Circle Blur: another smoothing filter.
Effects >
- Vignette: simulates the vignetting of a lens. Opens a dialog to enter the Inner and the Outer Radius.
- Randomize: fills a picture with random pixel values.
- Sepia tone…: opens the colour picker dialog. Converts to a monochrome picture with the colour selected. If white is selected, a black-and-white picture is produced.
- Quantize: seems to set the highest pixel value to 1.
- Signed Quantize: negative pixel values may emerge.
- DXC9000 Curve: adaption to the response curve of the 1/2" 3 CCD Progressive Scan Video Camera by Sony. (Professional studio video camers, price about $ 6,500.)