DPS wide dynamic technology-based exploration and practical application (1)

In camera development years from initial vacuum tube camera development to CCD, CMOS, DPS camera, along with the camera application, a variety of dedicated camera technology, wide dynamic technology is one of them.

For some dark contrast strongly to the special circumstances, an ordinary camera for images of the most "hidden" and the "light" section of the balance adjustment ability is very limited when it wide dynamic technology can play a prominent role.

DPS wide dynamic technology

In backlighting, generally using super wide dynamic camera, super wide dynamic camera's dynamic range represents a camera the image of the "dark" and "light" adjustment range, dynamic range, the larger the image of the layer will be rich, clear, of course, the image's color space is more extensive, super wide dynamic camera adjust backlighting the ability of the environment.

Traditional CCD camera to capture an image of the entire image sampling only once, so it will appear on the whole image in the bright area overexposed, or darker areas underexposed.

Despite the wide dynamic CCD camera compared with traditional CCD camera, technically have repeatedly break, now third generation CCD wide dynamic camera, wide dynamic range also reached 160 times, or say 54dB.

But there are information disclosure, CCD wide dynamic camera's dynamic range can reach up to 60dB. Has now been launched based on CMOS technology, the DPS wide dynamic camera, its wide dynamic range generally can achieve up to 95dB, 120dB.

DPS technology features on each pixel for several separate no-loss sampling, the dynamic range increase, bluntly wide dynamic camera is using multi-exposure technique balance adjustment and dark images, vivid scenes of real effects.

DPS (Digital Pixel System) is a digital image sensor processing system, its core technology is a pick of pixels contains an ADC (analong — to — digited DAC), when the ADC capture the light signals are directly converted to digital signals and zoom, which maximize the savings of invalid transfer operation, reduces noise, guarantee the high quality of image, makes the output image is no smearing and flowering phenomenon.

DPS system in the entire image acquisition, transfer and processing, whether on the front of the pickup or the back-end processing completely to digital forms, is truly pure digital image sensor system.

United States Pixim company at Stanford University in the 1990s technology development on the basis of the development of a new type of DPS image pickup system, this system makes the super wide dynamic features to get high quality pictures.

From Stanford Pixim's DPS imaging technology, applied for patents, of which 56 42 items are in force. Pixim's DPS technology is currently the only direct to digital value represents the optical signal image capture system. CCD and CMOS sensors with analog value represents the light signal, then the analog value converted to a numeric value, DPS is non-existent analog readout noise.

In DPS technology in each pixel has an ADC, each pixel information is independent of capturing and processing, and use a 32bit ARM7 CPU processing chips (or ARM9) to control each pixel's exposure time, making the mold — the number conversion accuracy.

The sensor can be used in exposure period on each pixel light multiple times and high-speed sampling and control each pixel's exposure time, in its best state storage pixel information, so that each pixel has been repeatedly (0.8ms) non-destructive sampling of individual. In pixel is acquisition, the system then processes it, eventually forming a high-quality images. DPS system formation of image in horizontal and vertical resolution consistency, any angle can be assured of high resolution images.

Pixim's patent DPS technology marks in camera technology in a fundamental breakthrough to CCD camera for mainstream technology will be huge impact DPS technology.

DPS technology to restore sexual concepts, imaging, image quality is high, the use of DPS technology allows each pixel of the exposure time is different, so that the same scene in different parts of the exposure time varies.

Therefore, the entire image to any point, you can achieve the best image display of status, to get a clear image detail, closer to the real scene of color reproduction.

Pixim company said DPS technology "each pixel is a camera (Every pixel is a camera)", in an image, the exposure there are hundreds of thousands of pixels, even in the most harsh lighting conditions, but also to capture clear, lifelike image, never as shadow, reflection and glare, sunlight makes the image darker or damaged hair.

Therefore, in the technology, the DPS every pixel corresponds to the light can be optimized exposure, the final formation of high-quality images.

DPS camera is with "eye-brain" system the same work mode, the image sensor and image processor that has a two-way real-time interaction.

DPS camera image ingest and handling process, similar to the human eye and brain, image processing and operations at the same time, the image sensor release directive, not only to adjust the exposure time, and change the actual algorithm for image capture, enabling intelligent image processing features.

Therefore, in the specific image features and illumination, DPS camera eventually provide more detailed, complete and true image detail, in order to get the best image effects.

DPS wide dynamic technical characteristics

From the preceding description can know wide dynamic technology is applied to the strong light and cross environment, can also be understood as two environments, an overly excessive exposure to another, as in a relatively dark room and room

Diplomatic poor environments, camera installation Interior, exterior and Interior to be two different environmental performance clear, wide dynamic technology must be used to achieve the effect of restoring the image.

DPS camera with CCD camera has the same high definition, in color, white balance compensation, vertical, outline, and so on-spot fully reflects the DPS camera stand out.

Use own OSD can set a number of features and adjust a number of parameters to ensure that on many occasions of monitoring requirements. The following describes the DPS camera some main characteristics:

1. minimum illuminance

1Lux/F1.4 (AGC ON 50IRE) 0.75Lux/F1.2, (50IRE AGC ON), 0.01Lux/F1.2 (electronic sensitivity enhancement max 32 x).

WDR 2, wide dynamic range

95dB typical values, Max 120dB, 36 adjust-level.

3, backlight compensation

Backlight compensation has the following four options.

· OFF, do not set the backlight compensation;

· ON, usually full range backlight compensation;

· 1SPOT, 1 regional backlight compensation, through the settings you can select the backlight compensation area size and location;

· 2SPOT, 2 regional backlight compensation, by setting can be selected 2 backlight compensation area size and location.

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