Is the official seal on the document still red after fax?

Look at the types of fax machines on both sides. If it is a color fax machine, the official seal is still red after fax.

Photography in color fax technology can obtain a color copy similar to the original. At the transmitter, color correction and other processing should be carried out, and then sent to the channel for transmission in a certain way.

Color fax machine is a kind of fax machine that transmits and copies color words, charts and graphics. Color fax technology includes camera shooting, transmission and recording, which involve three primary colors decomposition, color signal transmission and color reproduction technology respectively. The sending part decomposes the color manuscript into three primary colors (red, green and blue), and inputs them into photoelectric conversion devices to generate corresponding electrical signals.

Extended data

Document fax machine:

This is a fax machine, which copies the original with black and white optical density grade. It is mainly suitable for copying handwritten, typed or printed documents, charts and halftone images with limited black and white levels. Widely used in office, transaction processing and other fields.

According to the difference of telecommunication network, signal processing technology and transmission time of standard format manuscripts, document fax machines can be divided into one type for public telephone network, two types for public data network, three types for fax machines and four types for fax machines.

References:

Color Fax Machine-Baidu Encyclopedia