工作原理使用建議點(diǎn)云以下是原文How it worksUsability tipsPoint clouds

原文鏈接：https://developers.google.com/tango/overview/depth-perception

工作原理

深度感知技術(shù)能讓應(yīng)用感知現(xiàn)實(shí)世界中物體之間的距離。想要讓Tango 設(shè)備具備該能力，設(shè)備生產(chǎn)廠商可以從幾個(gè)常見的深度感知技術(shù)中選擇一種并實(shí)現(xiàn)之：結(jié)構(gòu)光（Structured Light），TOF 相機(jī)（Time of Flight），立體相機(jī)。（關(guān)于這三種技術(shù)，參見 《High-Fidelity Augmented Reality Interactions》——譯者注）。其中，前兩種技術(shù)需要使用紅外投影儀和紅外線傳感器，而立體相機(jī)不需要。

深度感知技術(shù)可以應(yīng)用于諸多場景中：

使用建議

當(dāng)前的tango設(shè)備是為室內(nèi)場景設(shè)計(jì)的，在室內(nèi)大約 0.5-4米的距離范圍內(nèi)效果最優(yōu)。這種設(shè)計(jì)能夠最好的兼顧紅外線和數(shù)據(jù)計(jì)算帶來的耗電，并保證獲取的深度數(shù)據(jù)最優(yōu)。而對(duì)于近距物體掃描或手勢檢測，效果卻不理想。 有些設(shè)備是使用相機(jī)觀測紅外線來實(shí)現(xiàn)深度感知的，這些設(shè)備在某些情景下無法實(shí)現(xiàn)精確的深度感知。比如，由于日光或白熾燈中含有大量的紅外線，所以日光或白熾燈覆蓋的區(qū)域，以及無法反射紅外線的物體，都是無法被感知的。

點(diǎn)云

tango API 以點(diǎn)云的形式返回深度數(shù)據(jù)。點(diǎn)云中包含當(dāng)前環(huán)境中能夠獲取的盡可能多的(x, y, z)坐標(biāo)，每一維數(shù)據(jù)都是浮點(diǎn)型，單位是米，表示其在坐標(biāo)幀中位置。

更多信息，見 TangoPointCloud 結(jié)構(gòu)體。

以下是原文

How it works

Depth Perception gives an application the ability to understand the distance to objects in the real world. To implement Depth Perception, manufacturers of Tango devices can choose among common depth technologies, including Structured Light, Time of Flight, and Stereo. Structured Light and Time of Flight require the use of an infrared (IR) PRojector and IR sensor; Stereo does not.

Depth Perception can be useful in a number of ways:

Usability tips

Current devices are designed to work best indoors at moderate distances (0.5 to 4 meters). This configuration gives good depth at a distance while balancing power requirements for IR illumination and depth processing. It may not be ideal for close-range object scanning or gesture detection.

For a device that relies on viewing IR light using its camera, there are some situations where accurate Depth Perception is difficult. Areas lit with light sources high in IR like sunlight or incandescent bulbs, or objects that do not reflect IR light, cannot be scanned well.

Point clouds

The Tango APIs provide a function to get depth data in the form of a point cloud. This format gives (x, y, z) coordinates for as many points in the scene as are possible to calculate. Each dimension is a floating point value recording the position of each point in meters in the coordinate frame of the depth-sensing camera.

For more information, see the TangoPointCloud struct API reference.