What is an X-ray?

X-rays are photos taken by x-ray penetrating irradiation. Mostly used for medical treatment.

Gray filter is to turn a picture into a gray image; Inverse filter inverts all visual attributes of the object, including color, saturation and brightness values; X-ray filter is to make an object reflect its contours and highlight these contours, which is the so-called "X" optical film.

X-rays are audio-visual materials.

Audio-visual materials include audio tapes, video tapes, cinematographic films or sounds, moving images and graphics stored in computer-related equipment. Knowledge carrier, also known as audio-visual materials or direct-feeling materials, is generally recorded in the form of sound and image. Audio-visual materials can generally be divided into three types:

(a) image data, also known as silent image data, including pictures, photographic films, slides, slides, silent videos, silent movies, silent machine-readable films, etc.

(2) Auditory materials, also known as recorded materials, include records and tapes.

(3) Audio-visual materials, also known as audio-visual materials or audio-visual materials, include movies, TV series, audio-visual films, audio-visual CDs, etc.