US 5,253,302 A · Method and arrangement for automatic optical classification of plants

Abstract

For automatic optical classification of plants an image of in each case one plant is captured by a color video camera. The color video signals furnished by the color video camera are digitized and classified pixelwise in predetermined color classes which are associated on the one hand with the image of the plant and on the other hand with the image of the background. A digitized image of the plant designated by the color classes is stored in an image memory and evaluated by an image computer for classification of the plant. The segmentation of the image of the plant from the image of the background is carried out on the basis of the allocation of the pixels to the predetermined color classes and from the segmented image of the plant geometrical form features and color features are determined. Furthermore, the height of the plant is determined, for which purpose possibly two video cameras and a light pattern projector are employed. The color classifier used for color classification is configured so that it can learn the predetermined color classes by presentation of image fragments.

Claims22

Dependent claims

A method for automatic optical classification of plants comprising the steps of:

(a) obtaining an image of a plant with a color video camera;
(b) digitizing pixelwise the color video signals obtained by the color video camera;
(c) classifying pixelwise the digitized color video signals in accordance with predetermined color classes, said color classes comprising sets of arbitrarily arranged color vectors to which a respective class code is attributed to under supervised learning on the basis of their belonging to the same meaningful regions;
(d) segmenting the image of the plant from at least one of the image of the background and the images of different parts of the plant from one another on the basis of the allocation of the pixels of the stored image to the predetermined color classes;
(e) determining at least one of geometrical form features and color features from at least one of the segmented image of the plant and the segmented images of the plant parts;
and
(f) evaluating at least one of the determined form features and color features for deriving a quality measure.

4 more elements

Method for automatic optical classification of plants comprising:

acquiring an image of in each case one plant by a color video camera, digitizing pixelwise video signals of the acquired image, storing a digitized image of the plant in an image memory and evaluating the stored digitized image by an image computer for classification of the plant, classifying pixelwise the digitized color video signals prior to storing of the digitized image in accordance with predetermined color classes which are assigned on the one hand to the image of the plant and on the other to the image of the background, effecting the segmentation of the image of the plant from the image of the background on the basis of the allocation of the pixels to the predetermined color classes, determining the segmented image of the plant geometrical form features and evaluating the form features for derivation of a quality measure, the color classification is effected by a color classifier comprising a memory having a plurality of memory cells each of which is allocated to a different color value in the color space, said color classifier being interactively trainable by presentation and said training includes:
a. erasing the contents of all memory cells of the memory of the color classifier;
b. displaying the image of a plant captured by the color video camera on a monitor;
c. marking a fragment containing as many pixels as possible of a color class to be identified by the user in the image displayed on the monitor;
d. incrementing in the memory of the color classifier, for each pixel of the marked image fragment the content of the memory cell allocated to the color value of the pixel;
e. designating all the memory cells having contents which due to the incrementations are greater than a predetermined threshold value as belonging to the color class to be identified after the evaluation of all the pixels of the marked image fragment;
and
f. repeating steps c to e for each further color class to be identified.

5 more elements

Arrangement for automatic optical classification of plants comprising:

(a) two color video cameras arranged at a distance apart and directed onto the plant in such a manner that they capture a stereo image of the plant;
(b) an analog-digital converter arrangement for separately digitizing pixelwise the analog image signals furnished by the one and the other color video camera;
(c) a color classifier for classifying the digitized color video signals corresponding to the image captured by one of said two color video cameras pixelwise in accordance with predetermined color classes which are assigned on the one hand to the image of the plant and on the other hand to the image of the background;
(d) means for effecting the segmentation of the image of the plant from the image of the background on the basis of the allocation of the pixels to the predetermined color classes;
(e) means for determining geometrical form features from the segmented image of the plant;
(f) an image memory for storing the digitized stereo image represented by said digitized color video signals;
(g) a height computer performing a search for associated pixel pairs in the stored digitized stereo image in search regions corresponding to plant parts which have been segmented by means of said color classification and determining the height of said plant parts from the pixels of each pair ascertained by the search;
and
(h) means for deriving a quality measure from both said geometrical form features and the heights of said plant parts.

6 more elements

Dependencies are inferred from the claim text.

Method and arrangement for automatic optical classification of plants

Life of this patent

Method and arrangement for automatic optical classification of plants

Life of this patent

Abstract

Claims22