TWI456185B - Water turbidity detection system and the method thereof - Google Patents

Claims (24)

A water quality detecting system for detecting the turbidity of a water source to be tested, the system comprising: an illuminator for transmitting a dimming light from the water source to be tested to the measured water source; and an image capturing device continuously Taking a plurality of water surface images of the surface of the tested water source, each of the water surface images including a gradation image generated by the same dimming light colliding with the suspended particles in the tested water source on the surface of the tested water source, the gradation image The brightness is enhanced from the edge to the center; and a processor receives the water surface images and defines a scattering block of each of the water surface images according to at least one brightness threshold, the scattering block corresponding to the high brightness of the water surface image a region, the processor separately calculating an area parameter of the scattering blocks, and screening the scattering blocks according to a screening value ratio, and according to the scattering blocks retained after the screening The area parameters obtain a parameter statistical value, and the turbidity of the measured water source is determined according to a turbidity comparison table to determine the turbidity of the measured water source; wherein the larger the statistical value of the parameter, the measured water The higher the turbidity. The water quality detecting system of claim 1, wherein the brightness threshold includes a first threshold value, and the processor divides each pixel of each of the water surface images into a first one according to the first threshold value. One of a pixel value and a second pixel value to generate a first binary image, wherein the pixel values of the pixels corresponding to the scattering block are the first pixel value. The water quality detecting system of claim 2, wherein the processor performs grayscale processing on the water surface images to form a plurality of grayscale images, and the processor compares each of the first threshold values according to the first threshold value. The pixels of the grayscale images are respectively assigned to the pixel values of the pixels as one of the first pixel value and the second pixel value, thereby generating the first binary image. The water quality detecting system of claim 2, wherein each of the first binary images comprises at least one first block formed by a plurality of pixel groups corresponding to the first pixel value, The processor calculates a number of blocks of the first block of each of the first binary images, and reserves the first binary image of the number of blocks as a plurality of candidate images, wherein the The first block included in the candidate image corresponds to the scattering block. The water quality detecting system of claim 4, wherein the processor calculates a first block area of the first block of each of the candidate images as the area parameter. The water quality detecting system of claim 4, wherein the brightness threshold further comprises a second threshold value, and the processor, according to the second threshold value, corresponds to the grayscale images of the candidate images. The pixel values of the pixels are respectively designated as one of a third pixel value and a fourth pixel value to generate a plurality of second binary images, wherein one of the plurality of the third pixel values is formed The second block corresponds to the scattering block. The water quality detecting system of claim 6, wherein the processor separately calculates a second block area of the second blocks, and calculates the second block area of each of the candidate images. A ratio relative to the area of the first block is the area parameter. The water quality detecting system of claim 7, wherein the second threshold value is greater than the first threshold value, and the second block area in each of the candidate images is smaller than the first block area. The water quality detecting system of claim 5, wherein the processor filters the area parameters according to the screening value, and retains the candidate images whose area parameters are not greater than the screening value, and according to The parameter values of the candidate image images that are retained are calculated. The water quality detecting system of claim 9, wherein the screening value is an average of the area parameters of the candidate images retained by the processor. The water quality detecting system of claim 9, wherein the processor performs at least two screenings according to the screening value. The water quality detecting system of claim 2, wherein the processor erodes and expands the binary images to eliminate the burr effect of the binary images. A water quality detecting method for detecting turbidity of a water source to be tested by using an illuminator, an image capturing device and a processor, the method comprising: transmitting, by the illuminator, a homology from the surface of the tested water source to the water source under test The image capturing device continuously captures a plurality of water surface images of the surface of the tested water source, and each of the water surface images includes the same dimming light colliding with the suspended particles in the tested water source to generate on the surface of the tested water source a gradation image, the brightness of the gradation image is enhanced from the edge to the center; receiving the water surface images, and defining a scattering block of each of the water surface images according to at least one brightness threshold, the scattering block corresponding to a high-luminance region of the water surface image; respectively calculating an area parameter of the scattering blocks, and screening the scattering blocks according to a screening value ratio; according to the scattering blocks retained after the screening The area parameters obtain a parameter statistical value; and compare the statistical value of the parameter with a turbidity comparison table to determine the turbidity of the tested water source; wherein the larger the statistical value of the parameter, the The higher the turbidity of the water. The water quality detecting method of claim 13, wherein the step of defining the scattering block of each of the water surface images according to the brightness threshold comprises: according to a first threshold value of the brightness threshold, Dividing a plurality of pixels of each of the water surface images into one of a first pixel value and a second pixel value to generate a first binary image; wherein the pixels corresponding to the scattering block The pixel value is the first pixel value. The water quality detecting method according to claim 14, wherein before the generating the first binary image according to the water surface image, the method further comprises: grayscale processing the water surface images to form a plurality of grayscale images. And determining, according to the first threshold, the pixels of each of the grayscale images as one of the first pixel value and the second pixel value to generate the first binary image. The water quality detecting method of claim 14, wherein after the generating the first binary image, the method further comprises: calculating, by each of the first binary images, a plurality of pixels corresponding to the first pixel value The number of blocks of the at least one first block formed by the clustering; and the first binary image with the number of the blocks being one of the plurality of candidate images; wherein the candidate image includes the first A block corresponds to the scattering block. The method for detecting water quality according to claim 16 , wherein after selecting the binary images of the number of blocks as the candidate images, the method further comprises: calculating each of the selected candidate images. A first block area of the first block is the area parameter. The water quality detecting method of claim 14, wherein the selecting the first binary image of the number of blocks to be a plurality of candidate images further comprises: following a second threshold of the brightness threshold a value, the pixel values of the grayscale images corresponding to the candidate images are respectively designated as one of a third pixel value and a fourth pixel value, to generate a plurality of second binary images; One of the second pixel value clusters forms a second block corresponding to the scattering block. The water quality detecting method of claim 18, wherein after generating the second binary images, the method further comprises: separately calculating a second block area of the second blocks; and calculating each The ratio of the area of the second block of the candidate image to the area of the first block is the area parameter; wherein the second threshold is greater than the first threshold, the first of each candidate image The area of the second block is smaller than the area of the first block. The water quality detecting method of claim 17 or 19, wherein after calculating the area parameters of the candidate images, the method further comprises: screening the area parameters according to the screening value, and retaining the area parameter The candidate image is greater than the screening value; and the parameter statistics are calculated according to the area parameters of the candidate images that are retained; wherein the screening value is the area parameters of the candidate images that are retained average value. The water quality detecting method of claim 14, wherein the generating the first binary image further comprises: etching and expanding the binary image to eliminate the burr effect of the binary image . A method for correcting a water quality detecting system according to claim 1, comprising: continuously detecting the measured water source to determine the turbidity of the water source under test when the illuminating power of the illuminator is not attenuated; recording the illuminating The illuminating power of the device is not attenuated and the turbidity of the measured water source for a period of time is one of the corrected turbidity values, and a corrected turbidity range is generated according to the corrected turbidity value and an error value; the correction is generated After the turbidity range, the water surface images of the tested water source are continuously captured, and the statistical values of the measured parameters are analyzed and calculated to determine the turbidity of the tested water source; and the turbidity of the tested water source is determined to last for the length of time When the level is clear, calculating the parameter statistic values within the length of time to generate a reference turbidity value; comparing the reference turbidity value with the corrected turbidity range to determine whether the reference turbidity value is less than the corrected turbidity value The lower limit of the range; and when the reference turbidity value is less than the lower limit of the corrected turbidity range, the illuminating power of the illuminator is increased according to a compensation ratio. The method of claim 22, wherein, after the illuminating power of the illuminator is increased according to the compensation ratio, the method further includes: capturing the water surface images of the water source to be measured to calculate another parameter statistic value. And comparing whether the statistical value of the other parameter is not less than a lower limit of the corrected turbidity range; and when the statistical value of the other parameter is not less than a lower limit of the corrected turbidity range, completing the correction of the water quality detecting system . The method of claim 22, wherein the corrected turbidity value is an average of the statistical values of the parameter calculated over the length of time.