Methods and systems for determining frames and photo composition within multiple frames

Abstract

Methods and systems for determining frames and photo composition within multiple frames are provided. First, a plurality of frames, which are respectively captured with a predefined time interval are obtained. At least one object within at least two of the frames is detected. In some embodiments, a moving speed of the object is calculated according to the positions of the object in the respective frames and the predefined time interval, and candidate frames are selected from the frames according, to the moving speed of the object. In some embodiments, an overlapped area corresponding to the object within a first frame and a second frame is calculated, and at least one candidate frame is selected according to the overlapped area corresponding to the object. The at least one candidate frame is composed to generate a composed photo.

What is claimed is: 
     
         1 . A method for determining frames within multiple frames for use in an electronic device, comprising:
 obtaining a plurality of frames, wherein the respective frames are captured with a time interval;   detecting at least one object within at least two of the frames;   calculating a moving speed of the object according to the positions of the object in the respective frames and the time interval; and   selecting candidate frames from the frames according to the moving speed of the object.   
     
     
         2 . The method of  claim 1 , wherein the step of detecting at least one object within at least two of the frames comprises the steps of:
 transforming the at least two frames into grayscale frames; and   subtracting the grayscale frames with each other to obtain a contour of the object.   
     
     
         3 . The method of  claim 1 , wherein the step of selecting candidate frames from the frames according to the moving speed of the object comprises the steps of:
 looking up a table according to the moving speed of the object to obtain a frame gap number; and   selecting the candidate frames within the frames at intervals of the frame gap number.   
     
     
         4 . The method of  claim 3 , wherein the faster the moving speed is, the larger the frame gap number is. 
     
     
         5 . The method of  claim 1 , further comprising recording a video, and the frames are obtained from the video. 
     
     
         6 . A method for determining frames within multiple frames for use in an electronic device, comprising:
 obtaining a plurality of frames, wherein the respective frames are captured with a time interval;   detecting at least one object within at least two of the frames:   calculating an overlapped area corresponding to the object within a first frame and a second frame; and   selecting at least one candidate frame according to the overlapped area corresponding to the object.   
     
     
         7 . The method of  claim 5 , wherein the step of selecting at least one candidate frame according to the overlapped area corresponding to the object comprises the steps of:
 determining whether the overlapped area corresponding to the object is less than a specific percentage of a contour area of the object;   if the overlapped area corresponding to the object is less than a specific percentage of the contour area of the object, selecting the second frame as the candidate frame.   
     
     
         8 . The method of  claim 6 , wherein the step of selecting at least one candidate frame according to the overlapped area corresponding to the object comprises the steps of:
 determining whether the overlapped area corresponding to the object equals to zero;   if the overlapped area corresponding to the object equals to zero, calculating a moving speed of the object according to the positions of the object in the respective frames and the predefined time interval;   selecting candidate frames within the frames according to the moving speed of the object.   
     
     
         9 . The method of  claim 6 , wherein the step of detecting at least one object within at least two of the frames comprises the steps of:
 transforming the at least two frames into grayscale frames; and   subtracting the grayscale frames with each other to obtain a contour of the object.   
     
     
         10 . The method of  claim 8 , wherein the step of selecting candidate frames within the frames according to the moving speed of the object comprises the steps of:
 looking up a table according to the moving speed of the object to obtain a frame gap number; and   selecting the candidates frames within the frames at intervals of the frame gap number.   
     
     
         11 . The method of  claim 10 , wherein the faster the moving speed is the larger the frame gap number is. 
     
     
         12 . The method of  claim 6 , further comprising recording a video, and the frames are obtained from the video. 
     
     
         13 . A system for determining frames within multiple frames for use in an electronic, device, comprising:
 a storage unit comprising a plurality of frames, wherein the respective frames are captured with a predefined time interval; and   a processing unit detecting at least one object within at least two of the frames, calculating a moving speed of the object according to the positions of the object in the respective frames and the predefined time interval, and selecting candidate frames from the frames according to the moving speed of the object.