What does image processing mainly discuss? What's the use? What is it used for? What factors should be considered to solve a problem?

Digital image processing is an interdisciplinary subject. It is the most promising and challenging field for the intelligent development of technology in the future. Its research field is extensive and profound, and its application field is very extensive, and each field can make people settle down.

1.( 1) Typical applications of digital image processing: image compression and transmission (or image communication is also possible) (such as JPEG compression standard for still images; Dynamic MPEG standard, the similar standard in telecommunications is H.264, and MP4 in entertainment also belongs to this aspect). The main research content is to develop more effective image coding and decoding algorithms (there are many hardware-implemented coding and decoding chips, and the specific performance indicators are different from the applicable standards).

(2) Biometrics is the application of digital image processing in the field of information security (including fingerprint recognition, iris recognition, face recognition, etc. Of course, the license plate recognition used in the traffic system is also a similar technology. The general mode is: image preprocessing (such as denoising, enhancement, etc. )+invariant feature extraction+matching with features in feature library = > recognition;

Application of Biomedical Engineering Digital image processing is widely used in biomedical engineering and is very effective. In addition to CT technology, there is also the processing and analysis of medical microscopic images, such as red blood cell and white blood cell classification, chromosome analysis, cancer cell identification and so on. In addition, image processing technology is also widely used in X-ray lung image sharpening, ultrasonic image processing, electrocardiogram analysis, stereotactic radiotherapy and other medical diagnosis.

Medical image processing: CT imaging, magnetic resonance imaging, ultrasound, X-ray imaging. . .

Main research contents: image denoising, image enhancement, image recognition, 3D visualization, etc.

(3) The application fields of digital image processing that really concentrate on the most advanced software and hardware are:

Military: First of all, image data types include images that can be obtained in all imaging frequency bands (such as radio (radar imaging), infrared, visible light, ultraviolet and X-ray). . . Open the electromagnetic spectrum to understand), it is also possible to use acoustic echo imaging, such as sonar. Don't unilaterally understand that the image is visible light imaging, which is the limitation of human eyes.

The application of military public security in military image processing and identification is mainly used for accurate terminal guidance of missiles, interpretation of various reconnaissance photos, military automatic command system with image transmission, storage and display, and simulation training system of aircraft, tanks and warships. Public security service picture interpretation and analysis, fingerprint identification, face recognition, incomplete picture restoration, traffic monitoring, accident analysis, etc. The automatic recognition of vehicles and license plates in the expressway automatic toll collection system that has been put into operation at present is an example of the successful application of image processing technology.

It mainly includes these research contents: target capture, target locking and target tracking.

Robot Vision: Ah, robots are still stupid nowadays. It's great to be able to bypass obstacles by yourself.

(4) In terms of aircraft remote sensing and satellite remote sensing technology. Many countries send many reconnaissance planes every day to take a large number of aerial photographs of areas of interest on the earth. In the past, thousands of people needed to be employed to process and analyze the photos. Now, the image processing system equipped with advanced computers is used to interpret and analyze the photos, which not only saves manpower, but also accelerates the speed, and can also extract a lot of useful information from the photos that cannot be found manually. Since the late 1960s, the United States and some international organizations have launched resource remote sensing satellites (such as LANDSAT series) and sky laboratories (such as SKYLAB). Because the imaging conditions are affected by the position, attitude and environmental conditions of the aircraft, the image quality is always not very high. Therefore, it is not economical to obtain images through simple and intuitive interpretation at such an expensive price, and digital image processing technology must be adopted. For example, LANDSAT series Landsat satellites use a multi-band scanner (MSS) to scan and image every region of the earth at a height of 900km with a period of 18 days, and its image resolution is roughly equivalent to more than ten meters on the ground or 100 meters (for example, LANDSAT-4 is launched at 1983 with a resolution of 30m). These images are processed (digitized and encoded) in the air and stored on magnetic tape. When the satellite passes over the ground station, it is transmitted at high speed, and then analyzed and interpreted by the processing center. Many digital image processing methods must be used in the imaging, storage, transmission and interpretation of these images. At present, all countries in the world are using the images obtained by land satellites to carry out resource surveys (such as forest surveys, marine sediments and fisheries surveys, water resources surveys, etc.). ), disaster detection (such as pest detection, fire and water detection, environmental pollution detection, etc. ), resource exploration (such as oil exploration, mineral exploration, geographical location exploration and large-scale project analysis, etc. ), agricultural planning (such as soil nutrition, water content, crop growth, yield estimation, etc.). ), and urban planning (such as. China has also carried out some practical applications in the above aspects and achieved good results. Digital image processing technology has also played a considerable role in weather forecasting and the study of other planets in space.

(5) Application in Communication Engineering At present, the main development direction of communication is multimedia communication combining voice, text, image and data. Specifically, telephone, television and computer are transmitted in a three-in-one way on the digital communication network. Among them, image communication is the most complicated and difficult, because the amount of image data is huge, for example, the rate of transmitting color TV signals is above100 mbit/s. In order to transmit such high-speed data in real time, coding technology must be adopted to compress the bit amount of information. In a sense, coding compression is the key to the success or failure of these technologies. Besides entropy coding, DPCM coding and transform coding, new coding methods are being developed at home and abroad, such as progressive coding, adaptive network coding and wavelet transform image compression coding.

(6) Industrial and engineering applications Image processing technology has a wide range of applications in industrial and engineering fields, such as quality inspection and classification of parts on automatic assembly lines, defect inspection of printed circuit boards, stress analysis of elastic pictures, resistance and lift analysis of hydrodynamic pictures, automatic mail sorting, shape and arrangement identification of workpieces and objects in some toxic and radioactive environments, and industrial vision in advanced design and manufacturing technologies. It is worth mentioning that the development of intelligent robots with visual, auditory and tactile functions will bring new incentives to industrial and agricultural production, and have been effectively applied in painting, welding and assembly in industrial production.

(7) Applications in culture and art At present, such applications include digital editing of TV pictures, animation production, electronic video games, textile and handicraft design, costume design and production, hairstyle design, reproduction and restoration of cultural relics and photos, analysis and scoring of athletes' movements, etc. Now it has gradually formed a new art-computer art. ..