Image determining method and object coordinate computing apparatus

Abstract

An image determining method, for determining which pixels in an image are specific image pixels of a specific image, comprising: (a) determining which pixels in the image have brightness values larger than a threshold value; (b) determining the pixels having brightness values larger than the threshold value as the specific image pixels; and determining pixels in a predetermined range of at least one the specific image pixel as the specific image pixels as well.

What is claimed is: 
     
         1 . An image determining method, for determining which pixels in an image are specific image pixels of a specific image, comprising:
 (a) determining which pixels in the image have brightness values larger than a threshold value;   (b) determining the pixels having brightness values larger than the threshold value as the specific image pixels; and   (c) determining pixels in a predetermined range of at least one the specific image pixel as the specific image pixels as well.   
     
     
         2 . The image determining method of  claim 1 , wherein the step (c) comprises utilizing each of the specific image pixel as a center pixel of a pixel matrix to generate at least one pixel matrix, and the step (c) further comprising determining each pixel in the pixel matrix as the specific image pixel. 
     
     
         3 . The image determining method of  claim 1 , wherein a length and a width of the pixel matrix have the same amounts for pixels. 
     
     
         4 . The image determining method of  claim 1 , wherein the specific image pixel is generated by an object, where the image determining method further comprises:
 (d) computing a coordinate of the object according to the determining result of the steps (b) and (c).   
     
     
         5 . The image determining method of  claim 4 , further comprising:
 utilizing brightness values of the specific image pixels as a weighting, and utilizing the coordinate of the specific image pixels and the weighting to compute a gravity center of the object.   
     
     
         6 . An image determining method, for determining which pixels in an image are specific image pixels of a specific image, comprising:
 (a) scanning pixels of at least one row in an image in turn, and determining which pixels in the row is larger than a threshold value;   (b) determining at least one first row specific image pixel, which has a brightness value larger than a threshold value, in a first row to be the specific image pixel, and defines a specific image range according to the first row specific image pixel; and   (c) determining a second row specific image pixel inside the range, which is located in the specific image range of a second row after the first row, to be the specific image pixel while scanning the second row.   
     
     
         7 . The image determining method of  claim 6 , further comprising:
 (d) determining if pixels of the second row outside the specific image range have brightness values larger than the threshold value;   (e) if all the pixels of the second row outside the specific image range do not have brightness values larger than the threshold value, determining a third row specific image pixel inside the range, which is located in the specific image range of a third row after the second row, to be the specific image pixel while scanning the third row; and   (f) if at least one second row specific image pixel outside the range, which is located outside the specific image range of the second row, has a brightness value larger than the threshold value, determining the second row specific image pixel outside the range to be the specific image pixel, and updating the specific image range according to the second row specific image pixel outside the range; and determining pixels in the updated specific image range of the third row to be the specific image pixel while scanning the third row.   
     
     
         8 . The image determining method of  claim 6 , wherein the step (b) comprising determining a leftmost pixel of the first row specific image pixel as a leftmost edge of the specific image range, and determining a rightmost pixel of the first row specific image pixel as a rightmost edge of the specific image range. 
     
     
         9 . The image determining method of  claim 6 , further comprising:
 stopping scanning the image and stop updating the specific image range if no pixel is found to have a brightness value greater than the threshold value after scanning any row after the first row.   
     
     
         10 . The image determining method of  claim 6 , wherein the specific image pixel is generated by an object, where the image determining method further comprises:
 (d) computing a coordinate of the object according to the determining result of the steps (b) and (c).   
     
     
         11 . The image determining method of  claim 10 , further comprising:
 utilizing brightness values of the specific image pixels as a weighting, and utilizing the coordinate of the specific image pixels and the weighting to compute a gravity center of the object.   
     
     
         12 . An object coordinate computing apparatus, comprising:
 a camera, for catching an image, which is a gray level diagram, for at least one object;   a reading circuit, for scanning pixels of at least one row in an image in turn; for recoding brightness values and coordinates for the pixels; for defining an object range according to the brightness values and the coordinates for a first row of the rows; for determining first row object pixels in the object range of the first row to be the object pixels; and for determining a second row specific image pixel inside the range, which is inside the object range of a second row after the first row, to be the object pixel while scanning the second row;   wherein the reading circuit utilizes the recorded brightness values and the recorded coordinate to compute a gravity center of the object.   
     
     
         13 . The object coordinate computing apparatus of  claim 12 , wherein the reading circuit determines a leftmost pixel of the first row object pixel as a leftmost edge of the object range, and determines a rightmost pixel of the first row object pixel as a rightmost edge of the object range. 
     
     
         14 . The object coordinate computing apparatus of  claim 12 ,
 wherein the reading circuit determines if pixels of the second row outside the object range have brightness values larger than the threshold value;   where the reading circuit determines a third row object pixel inside the range, which is located in the object range of a third row after the second row, to be the object pixel while scanning the third row if all the pixels in the second row outside the object range do not have brightness values larger than the threshold value; and   if at least one second row object pixel outside the range, which is located outside the object range of the second row, has a brightness value larger than the threshold value, the reading circuit determines the second row object pixel outside the range to be the object pixel, updates the object range according to the second row object pixel outside the range, and determines pixels in the updated object range of the third row to be the object pixel while scanning the third row.   
     
     
         15 . The object coordinate computing apparatus of  claim 12 ,
 wherein the reading circuit stops scanning the image and stop updating the object range, utilizes the brightness values recorded before stop scanning as weighting, and utilizes the coordinate recorded before stop scanning and the weighting to compute a gravity center of the object;   if no pixel is found to have brightness values greater than the threshold value after scanning any row after the first row.