Blooming America

Cough, just have some mistakes, modified, slightly. (..) When I just hit "Don't believe in love", I accidentally pressed the delete, and there is also a content in the clipboard. Oh, one thing is not smooth, all things are not smooth ... So, please don't believe in love this stuff ... ... Time, gradually enter July 1982, 141 Special Warfare After several mission, after several mission, Under the leadership of the new rise of Ples, re-oscillating. Catherine also noticed that in response to their own plans, it seems to be stupid to move. But there seems no one knows that there is a forion that is not part of the two sides, this time is hidden in these people ... Nintendo Suchin, for the current Catherine, is already a small number 1286 new imaging and compression technology a small The role is, Catherine is not very much about this. Catherine's anti-terrorism elite, in fact, she cares is not just a game, Catherine is a feeling of like this kind of competitive, and likes this kind of e-sports game, at the same time, I like the first person shooting game game A hobby. However, this relationship with interest is the least. As a bond, it is a big digger, Catherine said that money is, it is actually a lot of people ... "Fang Zhou University has recently developed an imaging material, and they feel perhaps useful." Elsa Looking at the following file, then put it more importantly, and a document. It is an imaging device for an abnormal medium material. The material does not have the characteristics of the material in the natural world, and its structure is specially manually designed, with precise shape, size, arrangement, and direction. Sonic or optical waves can be affected in an unconventional manner. For example, the abutment medium material can "invisibility" of the optical wave, and can be curved. As a high noise reduction system. ... well, in addition to the new imaging and compression technology Catherine's tempered carbon nanotube fiber material, this stuff has the property, which is not less than the tempered carbon nanotube fiber. (.) Ark University, using the optical wavelength leakage characteristics of abutment medium materials, a device with new functions: microwave imaging system.

The system can compress the image while shooting - rather than using digital cameras and phones that people use to shoot after shooting.

Each pixel of the image in a digital camera is equivalent to information of a pixel recorded by the sensor in the camera. The traditional digital camera will use the algorithm to discard some data after collecting all the light intensity in the scene, and then compress into a JPEG file (unless you specify the store original data). The image quality thus obtained is also not bad because most of the discarding data is redundant.

Compressed sensing is intended to simplify this process by reducing the amount of data collected during initial shooting. One of the methods is a single pixel camera. Such devices use random mode to acquire information around the pixels around the image, from essentially, the light intensity value of some pixel blocks simultaneously increases. If you know the structure of the image in advance. For example, the dark sky corresponds to a bright star group, you can use less measured values ​​than conventional cameras to obtain information of the entire image.

Then, the collected set measurement can then be combined with the scene information that has been obtained, so that the computer can get the actual image from a large number of possible reconstruction pictures, which is only based on a group measurement.

However, such a microwave image compression system in the Ark University, is an effect of unfixed.

The system uses a special heterogeneous medium material. There is no lens or mirror, but through a radiation mode. Using this new system, the researchers use only 10 measurements to get 400 pixels (ie, the compression ratio is ... this is true "

The working principle is that the microwaves pass through the thin belt made of abutment medium materials, and there is a precision design of a plastic-separated metal coil randing along a 40 cm path from a special coil in the abutment medium material. These waves are then interfere with each other. When the optical wave of this mode is raised, the surface is reflected in its surface, and returns to the detector near the original heterogeneous medium material. The detector identifies the scene information by incorporating the intensity of the scattering beam and the waveform that leaves the coil, even if it captures a small portion of the entry material, it is already sufficient.

Its working principle is that the microwaves pass through the thin belt made of abutment medium materials, and there is a precision design of a plastic-separated metal coil random in a 40 cm path from a special coil in a special coil in the abutment medium material. These waves are then interfere with each other, and when the optical wave of this mode is reflected, the surface is reflected.

The researchers collect different imaging of an object by emission different frequencies ... From the transmission line. These frequencies are leaking along the waveguide of the abutment medium material, which produces a new radiation mode, and then enters the sensor. Using this set of measurements, we can rebuild images of images by algorithm, showing the distance from the perspective and objects to the camera, and this entire calculation process takes only 100 milliseconds. This speed is sufficient even for recording moving objects. However, the current microwave or millimeter wave detector is still very expensive, so general systems use fewer or smaller detectors. If there is a system to compress the image while shooting, and does not have to sacrifice image quality, it is a good way to reduce imaging costs.

This new heterogeneous medium material image compression system has no active components and lenses, and is also very thin. At the same time, a fast shooting speed means that one day when you accept security inspections at the airport, you only need to go straight to a millimeter wave scanning device without standing at the detector, Hunter. Say. He also envissed a heterogeneous medium imaging system on the car's car to create a collision system that can "look through" dust and fog.

This new technology will lead compressed sensing technology to a new era. Compared to the traditional imaging system, the microwave imaging system of abandoning the lens will greatly reduce the complexity of the system, so the cost of high-end camera, X-light scanning machine, and medical three-dimensional, etc. may be greatly reduced.

In general, a series of existing information is treated by a certain method such that its length is shortened, and the information content is basically or completely unchanged, it is called compression.

Compression process on the computer

We all know that the computer uses a 2-way system. A continuous N-bit binary number set can be used to represent 2 n characters. The current international standard is code: use a byte of the 8-digit 2 into code to represent various characters and letters.

Now we use 2-bit binary code to simply demonstrate the compression process of strings consisting of four symbols.

Suppose we have such a string of 20 letters data ... By default, these four letters are represented by 2 bits 2 ... Each character appears in the string. The number of times is not equal:

A: 6 times B: 10 times C: 3 times D: 1 time

In the computer, the data is stored on the hard disk in the form of a 2-coded code ... Saturing a new encoding:

Original encoding ... new code ... look! Data is successfully compressed. The content of this 40-bit length is compressed to 34 bits, and the compression ratio is 85%.

Reviewing the process is easy to find the secrets of compression: The most frequent frequency of 'b' is expressed by one binary code "0", and the frequency of more frequent 'c' and 'd', the three binary code increased by the length. To represent. By reasonably assigning the encoding of different lengths, it is certainly possible to compress the data to a certain extent.

It can also be proved that the Hoffman tree is one of the optimized programs of such encoding alternatives. Because if there is a result of the occurrence of characters above another, the length of the length is longer than another character, then the total length of the output result is minimized by switching the position of both. The case where it cannot be exchanged after the limited operation is limited, that is, the situation of Huffmann tree rules.

Another interesting question is: Although the 40-byte content is compressed to 34 bytes, it is necessary to send the corresponding code table to the recipient (no corresponding code table, cannot decompress). This does not make the compressed data are longer than the compression?

But this does not mean an algorithm error. This is because "N" is too small (2 in the example, actually 8) caused.

The total length is not enough to save the part of the capacity is not enough to make up for the storage space of the code table itself. In practical applications, if you have to compress one file with only a few bytes, the resulting compression package will often be greater than the file itself. Typically, the compression software regenerates and saves a Hofman tree after each compression of 4kb to 32kb data.

......

Tell everyone a funny joke: I believe in love.

Hahahahaha ~~~

PS (just just accidentally pressed the delete ...) RQ! ! !