"Gesture interaction" 9. PS Move

Sony has developed somatosensory control technology for more than 10 years, and in the past years has been experimenting with various technologies such as 3D cameras, ultrasound and electromagnetic induction, and finally considered the most appropriate technology for the current move. PS move was introduced by Sony in September 2010 to allow the PS3 host to have a dynamic sensing function controller. He uses the dynamic controller (handle) and the PS Eye camera to capture the player's movements and to give the player a new game operation mode.

Main handle (Dynamic controller)	Secondary handle (navigation controller)	PS Eye Camera

A set of PS Move controller consists of three parts: main handle, accessory handle, camera. The main handle (dynamic controller) uses a gyroscope, accelerometer, and geomagnetic sensor to accurately sense the player's hand movements, including slow motion and small twisting of the wrist. The sub-handle (navigation controller) is used in some games with the main handle to reflect more subtle movements and a real-world gameplay experience. The PS eye camera is capable of detecting the light bulb of the main handle, thus accurately calculating the player's information in three-dimensional space. The PS eye is a color camera with a standard fixed focal length lens that can be used to capture the background or the player's appearance, and then add the photo as part of the game.

PS move needs to be used in conjunction with the PS Eye camera, the camera takes pictures and finds the glowing ball, and determines its position in the three-dimensional space by the position and size of the glowing ball on the image. The farther away the ball is from the camera, the smaller the area of the image projected into the camera, and the distance between it and the camera can be accurately calculated based on the size of the light bulb in the image, thus determining its exact coordinates in three-dimensional space.

Luminous spheres are active (battery-powered, each full-time electricity, theoretically can provide 10 hours of use) actively illuminated spheres, made of soft plastic material, anti-collision. The light bulb has an RGB LED light which can be configured in any color. Color variable reason is: 1, enhance the contrast with the environment color, if the color of the room is too thick, the light ball will change into a more obvious color with its contrast, improve the accuracy of capturing the light bulb image; 2, depending on the picture in the game (such as the spark when shooting the color, brush color, etc.), Enhance the sense of input when playing.

The processing of images captured by the PS Eye camera is done in the PS3 cell processor, which consumes a bit of the SPU's processing power and consumes 1~2MB of system memory for action capture. The PS eye camera produces 60 frames per second, with a resolution of 640x480, which is accurate enough to measure millimeter-scale distance changes and 1-degree angle changes. Due to the use of the light-emitting ball method, simplifying the image processing algorithm (using a simple threshold segmentation method can be the light bulb and background segmentation), so the delay of PS move is very low, Sony said move the delay time of about 20 milliseconds, about 1 frame degree, This is already roughly the same speed as the standard DS handle, so it can be applied to games that require high operating accuracy and speed.

The advantage of PS move is that there is no need to deliberately align the front-end of the controller with the sensor, as long as the light ball can be positioned continuously within the visible range of the PS eye, with many degrees of freedom in handling. Another advantage of this approach is the ability to have more accurate space positioning, boxing games, for example, the General people holding the Wii Controller fist, Punch, the top of the Wii controller will not go forward, but will face up or toward the sides of the body, In this case, because the top of the Wii controller lens can not be seen usually placed in front of the player's infrared light source, so there is no way to detect the player's actual punch distance, but only with the strength of the acceleration to judge, to the PS move, in addition to using the acceleration to determine the player's punch strength outside, can also detect the distance of the ball of light to calculate the actual amount of punch out of the player, in this multiple detection mode, in the past to play the Wii in the short-wave speed controller to create large speed to deceive the program, so that the program mistakenly thought to be a powerful fist "lazy play" to the PS move on the use of.

Someone measured the delay problem of PS move, found that move game speed or there is a certain limit, when the player operation speed is too fast, more than the speed of the game, it is possible to be ignored, but in the fast continuous action will be more obvious (such as quick to cut 10 times, The game does not necessarily show the same action 10 times in full.

Another important factor that affects handling is the placement of the PS eye, which Sony suggests is positioned directly in front of the TV. When the camera angle is different, the angle of the captured screen is also different, if the camera is not placed well, will greatly affect the operability. Before the PS move game, the PS eye lens needs to be tuned to wide-angle mode, which gives the player more space to play. Each PS move game will have its own correction method, correct the player's position in the camera, the main handle light ball color and so on.

In fact, Sony in the PS3 period, by the Xbox 360 in the body sense of the impact of design, seems to have been a bit passive, the development of a separate camera and move body sense controller, but the effect is not ideal, the former and game combination of functional design is very limited, the latter support game is too little, It can be said that in the previous generation of somatosensory design, Sony was defeated.

PS4 Eye

The new PS4 eye body camera features a dual lens design and is equipped with multiple identification sensors and microphones, so the shape becomes longer. The PS4 eye can be fixed at the top of the TV by Sony or a third-party accessory, and it is easy to adjust the angle.

The PS4 Eye has a 85-degree, wide-angle, fixed-focus camera with two resolution of 1280*800, which not only accurately calculates the depth of field of the subject and the player's forward and backward movement, but also captures 1280*800 (60fps), 640*400 (120fps) and 320* 192 (240fps) Three sizes of video, output video format is raw or YUV data.

The device also has four high-sensitivity microphones that allow players to sign in to their PS4 with face recognition and voice recognition. PS4 Eye not only works with the PS move main handle (its control accuracy far exceeds the previous generation), but also interacts with the DualShock 4 handle. In a multiplayer game, the device can identify multiple players by the different colors shown in the DualShock 4 led block and record the different colors each player holds, and after that PS4 Eye will send each player their information in the game based on the color information they have recorded.

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"Gesture interaction" 9. PS Move