Anaglyph (from the Greek. Ἀνάγλυϕος “embossed”) is a method of obtaining a stereo effect for a stereo pair of ordinary images using color coding of images intended for the left and right eye . To obtain the effect, it is necessary to use special ( anaglyphic ) glasses, in which instead of lenses filters of a pair of complementary colors are inserted: as a rule, for the left eye - red , for the right - turquoise . A stereo image is a combination of stereo pair images in which a picture for the left eye is shown in the red channel (the right eye does not see it because of the light filter), and in turquoise (blue-green) - for the right. That is, each eye perceives an image painted in the opposite color .
3D glasses are required to view this image correctly.The main disadvantage of the anaglyph method is incomplete color rendering. Due to the effect of binocular color mixing, the formed volumetric image is perceived as monochromatic or (with a certain ratio of brightnesses) achromatic . Adaptation of the observer to specific conditions of perception occurs rather quickly. However, after a not so long (about 15 min) stay in anaglyphic glasses, the observer for a long (about half an hour) time decreases color sensitivity and there is a feeling of discomfort from the perception of the ordinary world.
Content
Creating Anaglyphs
In old methods using shooting filters and film, images for the right and left eye were printed or reproduced as a projection as a single image, or two images through special filters fell on one film. One passed through a red filter, and the other through a filter of a contrasting color - blue, green or turquoise. As emphasized below, it is now possible, predominantly using computer programs, to simulate the use of color filters. At the same time, you can take as a basis both a pair of monochrome and color images. Since the 1970s, Stephen Gibson has proposed his patented Deep Vision system, which uses turquoise filters instead of green. This allows you to achieve more natural colors, as the colors cover almost the entire visible spectrum. The red color is most distorted (it looks almost black), the least is green. Deep Vision glasses have a red filter on the right and turquoise on the left or red / cyan (to circumvent Gibson's patent, some companies produce red-turquoise glasses with filters in the opposite order)
The main tools for creating anaglyphs are in popular professional software, for example, in Adobe Photoshop , StereoPhoto Maker , Blender . The instructions for creating anaglyphs are not given in the official user guides, but they can be found on various sites offering free instructions for graphic editors. However, most of these instructions are silent that as a result of an attempt to make an anaglyph from one frame, a “pseudoanaglyph” without a stereo effect will be obtained, since the resulting stereo pair does not have parallax . The bottom line is that the color for each eye is set to RGB and if the glasses are red / cyan, then the pink picture will be split into two eyes, since in RGB pink is red + blue, and cyan = blue + green. There are also simple cheap programs for creating anaglyphs. For example, the free StereoPhoto Maker can create high-quality anaglyphs (and not just anaglyphs) for any type of glasses automatically. Currently, using simple approaches from the image for the left eye, blue and green colors are filtered out.
Television Application
In 1975-1978, the Leningrad Telecentre conducted experimental broadcasts of color stereo images using the anaglyphic method. The experiments were conducted in conjunction with the Department of Television LEIS .
Science Application
Anaglyph images are used to represent models of chemical molecules: proteins , RNA , etc.
See also
- Parallax
Links
- Virtual & Really.Ru - articles about stereo images, a selection of photographs and images in anaglyphic format
Literature
- Rozhkov S.N., Ovsyannikova N.A. Stereoscopy in film, photo, video equipment. - M .: Publishing house "Paradise", 2003.