Patent Publication Number: US-2011075889-A1

Title: Image processing system with ambient sensing capability and image processing method thereof

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an image processing system and related method, and more particularly, to an image processing system with ambient sensing capability and an image processing method thereof. 
     2. Description of the Prior Art 
     The advantages of a thin film transistor liquid crystal display (TFT-LCD) include portability, low power consumption, and low radiation. Therefore, the TFT-LCD is widely used in various portable products, such as notebooks, personal data assistants (PDAs), etc. Moreover, the TFT-LCD has gradually replaced the cathode ray tube (CRT) monitor in desktop computers. When a user watches the TFT-LCD, if the display screen of the TFT-LCD is too bright or a light is suddenly turned off, the pupil of their eye will be dilated; additionally, if the display screen remains bright, their eyes will be tired or even damaged. Therefore, the luminance of the display screen needs to be adjusted properly according to the ambient light intensity. The prior art design utilizes one or multiple dedicated photo detectors embedded in the computer device (e.g., notebook) to detect the ambient light intensity, so the illumination of the display screen or the backlight of a keyboard region can be adjusted automatically to obtain optimal brightness. Therefore, the user can easily and comfortably operate the computer device in a dark environment. However, a photo detector can only detect a light source that is located in a fixed direction. In order to perform light source detection or object movement detection in multiple directions, many photo detectors need to be utilized and the manufacturing cost is increased accordingly. 
     SUMMARY OF THE INVENTION 
     It is therefore one of the objectives of the present invention to provide an image processing system with ambient sensing capability and an image processing method, that solves the above mentioned problems. 
     According to an embodiment of the present invention, an image processing system with ambient sensing capability is disclosed. The image processing system includes an image sensing device and an ambient sensing device. The image sensing device is used for sensing a scene to generate original image data. The ambient sensing device is coupled to the image sensing device, for analyzing a part of the original image data to generate an ambient sensing result. 
     According to another embodiment of the present invention, an image processing method is disclosed. The method includes the following steps: sensing a scene to generate original image data; and analyzing a part of the original image data to generate an ambient sensing result. 
     The exemplary embodiments of the present invention provide an image processing system with ambient sensing capability and an image processing method. An ambient sensing result can be derived by performing image segmentation and luminance variation/object movement analysis upon an original image data captured by an image sensing device, so the illumination of a display screen or the backlight of a keyboard region can be adjusted according to the ambient sensing result to provide convenience of use for a user. 
     These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating an image processing system according to an exemplary embodiment of the present invention. 
         FIG. 2  is a diagram illustrating a scene captured by the image sensing device shown in  FIG. 1  via a fish-eye lens. 
         FIG. 3  is a diagram illustrating the image capturing viewpoints of the image sensing device shown in  FIG. 1  positioned on an upper cover of a notebook. 
         FIG. 4  is a flowchart illustrating an image processing method according to an exemplary embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Certain terms are used throughout the description and following claims to refer to particular components. As one skilled in the art will appreciate, electronic equipment manufacturers may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms “include” and “comprise” are used in an open-ended fashion, and thus should be interpreted to mean “include, but not limited to . . . ”. Also, the term “couple” is intended to mean either an indirect or direct electrical connection. Accordingly, if one device is coupled to another device, that connection may be through a direct electrical connection, or through an indirect electrical connection via other devices and connections. 
     Please refer to  FIG. 1 .  FIG. 1  is a diagram illustrating an image processing system  100  according to an exemplary embodiment of the present invention. In this embodiment, the image processing system  100  includes, but is not limited to, an image sensing device  110 , an ambient sensing device  120  and an image processing device  130 . The image sensing device  110  is used for sensing a scene to generate original image data D origin . The ambient sensing device  120  is coupled to the image sensing device  110 , and utilized for analyzing a partial image data D part  of the original image data D origin  to generate an ambient sensing result I R . The image processing device  130  is also coupled to the image sensing device  110 , and utilized for generating a processed image data D process  according to the original image data D origin . 
     The ambient sensing device  120  includes an image segmentation unit  122  and an image analyzing unit  124 . The image segmentation unit  122  is used for receiving the original image data D origin , and partitioning the original image data D origin  to generate a plurality of partitioned image data (e.g., D cut1 ˜D cutN ) according to a plurality of sensing regions (e.g., S region1 ˜S regionN ) of the image sensing device  110 , where the plurality of partitioned image data correspond to the plurality of sensing regions, respectively. The image analyzing unit  124  is coupled to the image segmentation unit  122 , and utilized for receiving at least one partitioned image data, and analyzing the at least one partitioned image data to generate the ambient sensing result I R , wherein the partial image data D part  includes at least one of the partitioned image data D cut1 ˜D cutN ; additionally, the number of sensing regions can be adjusted according to the application requirements. 
     In one exemplary embodiment, the image sensing device  110  captures the scene to generate the original image data D origin  via a wide-angle lens or a fish-eye lens. The fish-eye lens is a particular wide-angle lens that takes in an extremely wide, hemispherical image, which takes in a 180° hemisphere and projects this as a circle within the scene. Please refer to  FIG. 2  in conjunction with  FIG. 1 .  FIG. 2  is a diagram illustrating a scene captured by the image sensing device  110  shown in  FIG. 1  via the fish-eye lens. As shown in  FIG. 2 , the image sensing device  110  divides the scene captured by the fish-eye lens into three sensing regions S region1 ˜S region3  (i.e., the above-mentioned S region1 ˜S regionN , where N is equal to 3). The image sensing device  110  sets the sensing regions S region1 , S region2  and S region3  as an ambient light sensing region, a normal image region and an object movement sensing region, respectively. Please note that, in this embodiment, the image sensing device  110  captures the image of the scene via the fish-eye lens and divides the captured image into three sensing regions; however, this embodiment merely serves as an example for illustrating the present invention, and should not be taken as a limitation to the scope of the present invention. 
     The image segmentation unit  122  receives the original image data D origin , then partitions the original image data D origin  to generate the partitioned image data D cut1 ˜D cut3  (i.e., the above-mentioned D cut1 ˜D cutN , where N is equal to 3) according to the sensing regions S region1 ˜S region3  divided by the image sensing device  110 , where the partitioned image data D cut1 ˜D cut3  correspond to the sensing regions S region1 ˜S region3 , respectively. The image analyzing unit  124  receives the partitioned image data D cut1  and D cut3 , and the image processing device  130  receives the partitioned image data D cut2 . Because the partitioned image data D cut1  corresponding to the sensing regions S region1  has been set as the ambient light sensing region, the image analyzing unit  124  performs luminance variation analysis upon the partitioned image data D cut1  to generate an ambient sensing result I R1 . Generally, light sources of a scene are positioned on the upper position (e.g., ceiling of a room), so the luminance variation analysis performed upon the partitioned image data D cut1  corresponding to the sensing regions S region1  located at the top of the scene can derive a fairly precise ambient sensing result. Since the fish-eye lens has a wider viewpoint, the sensing regions S region1  is difficult to be sheltered, and therefore the luminance variation analysis can derive the ambient sensing result with minimal error. The partitioned image data D cut2  corresponding to the sensing regions S region2  has been set as the normal image region, and the image captured by the wide-angle lens or the fish-eye lens will be warped. Therefore, the image processing device  130  performs a de-warp operation upon the partitioned image data D cut2  to generate the processed image data D process . The partitioned image data D cut3  corresponding to the sensing regions S region3  has been set as the object movement sensing region, therefore, the image analyzing unit  124  performs object movement analysis upon the partitioned image data D cut3  to generate an ambient sensing result I R3 . Thus, the image sensing device  110  can perform ambient sensing and image processing simultaneously to generate the ambient sensing result I R  and the processed image data D process . 
     Please note that, in this embodiment, the image processing device  130  performs image processing operations upon the partitioned image data D cut2 ; however, this embodiment merely serves as an example for illustrating the present invention, and should not be taken as a limitation to the scope of the present invention. In an alternative design, the image processing device  130  can perform image processing operations upon the original image data D origin  directly to generate the processed image data D process . 
     With the development of multimedia, the prices of small digital cameras have steadily dropped. In this new era, a computer can broadcast images over a network via the addition of one small digital camera. Therefore, a small digital camera has become standard equipment in a notebook. If the ambient sensing capability of the photo detector is replaced by the small digital camera, the manufacturing cost of the notebook can be greatly decreased. Therefore, in another exemplary embodiment, the image processing system  100  is applied in a notebook NB, and the image sensing device  110  is implemented by a small digital camera positioned on the upper cover of the notebook NB. Please refer to  FIG. 3  in conjunction with  FIG. 1  and  FIG. 2 .  FIG. 3  is a diagram illustrating the image capturing viewpoints of the image sensing device  110  positioned on an upper cover of the notebook NB. As shown in  FIG. 3 , the capturing viewpoints A, B, C correspond to the sensing regions S region1 , S region2  and S region3  shown in  FIG. 2 , respectively. Because the light source of the scene is positioned at the sensing region S region1  covered by the capturing viewpoint A, the image analyzing unit  124  of the image processing system  100  performs the luminance variation analysis upon the partitioned image data D cut1  corresponding to the sensing regions S region1  to generate the ambient sensing result I R1 . As the normal image region is positioned at the sensing region S region2  covered by the capturing viewpoint B, the image processing device  130  of the image processing system  100  performs image processing operations upon the partitioned image data D cut2  corresponding to the sensing regions S region2  to generate the processed image data D process . The keyboard of the notebook NB is positioned at the sensing region S region3  covered by the capturing viewpoint C, and information relating to human hand movement can be detected at the sensing region S region3 . The image analyzing unit  124  therefore performs the object movement analysis upon the partitioned image data D cut3  corresponding to the sensing regions S region3  to generate the ambient sensing result I R3 . If the image analyzing unit  124  transmits the ambient sensing result I R1  to a control device (not shown in  FIG. 3 ) of the notebook NB, the control device can adjust the illumination of a display screen of the notebook NB or turn on/off the backlight of the keyboard according to the ambient sensing result I R1  for convenience of use by a user; if the image processing device  130  transmits the processed image data D process  to the control device of the notebook NB, the control device can display the processed image data D process  on the display screen according to user&#39;s requirement; additionally, if the image analyzing unit  124  transmits the ambient sensing result I R3  to the control device of the notebook NB, the control device can turn on/off the backlight of the keyboard according to the ambient sensing result I R3  for convenience of use by a user. 
     The abovementioned embodiments are presented merely for describing features of the present invention, and in no way should be considered to be limitations of the scope of the present invention. Those skilled in the art should readily appreciate that various modifications of the image sensing device  110  may be made for satisfying different requirements. For example, the image sensing device  110  can simply divide the captured scene into two sensing regions, and then the image analyzing unit  124  will perform luminance variation or object movement analysis upon a partitioned image data corresponding to one of the sensing regions to generate the ambient sensing result I R . This also falls within the scope of the present invention. 
     Please refer to  FIG. 4 .  FIG. 4  is a flowchart illustrating an image processing method according to an exemplary embodiment of the present invention. The image processing method of the present invention can be applied to the image processing system  100  shown in  FIG. 1 . Please note that the following steps are not limited to be performed according to the sequence shown in  FIG. 4  if a substantially identical result can be obtained. The exemplary method includes the following steps: 
     Step  402 : Sense a scene to generate original image data. 
     Step  404 : Partition the original image data to generate a plurality of partitioned image data according to a plurality of sensing regions, where the plurality of partitioned image data correspond to the plurality of sensing regions, respectively. 
     Step  406 : Analyze at least a partitioned image data to generate an ambient sensing result. 
     As those skilled in this art can easily understand the operations of steps  402 - 406  of the exemplary image processing method after reading the disclosure of the image processing system  100  shown in  FIG. 1 , full details are omitted here for brevity. Please note that the steps of the flowchart mentioned above are merely a practicable embodiment of the present invention, and should not be taken as a limitation of the present invention. The method can include other intermediate steps or can merge several steps into a single step without departing from the spirit of the present invention. 
     In summary, the present invention provides an exemplary image processing system with ambient sensing capability. The image processing system performs image segmentation and luminance variation/object movement analysis upon an original image data captured by an image sensing device to generate an ambient sensing result so the illumination of a display or the backlight of a keyboard region can be adjusted according to the ambient sensing result to provide convenience of use for a user. In addition, the exemplary image processing system can also perform image processing operations upon the captured image data to generate processed image data simultaneously. 
     Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention.