IMAGING SYSTEMS AND METHODS USEFUL FOR SIGNAL EXTRACTION
Disclosed herein, inter alia, are methods and systems of image analysis useful for identifying and/or quantifying features in patterns.
1 . A method of quantifying features in a repeating pattern of an object, the method comprising:
obtaining a plurality of images of the object using a detection apparatus, wherein the plurality of images includes a repeating pattern of features having different signal levels;
providing the images or image-related data to a computer, wherein the computer has parameter data that describe the repeating pattern of features;
partitioning the image or the image-related data into a plurality of registration subimages on the computer;
detecting on the computer the repeating pattern of features for each registration subimage;
assigning an index address for each feature of the repeating pattern of features; and
quantifying a signal level of each feature.
2 . The method of claim 1 , wherein the signals are fluorescent intensities.
3 . The method of claim 1 , further comprising providing the object, wherein the object has a repeating pattern of features in a two-dimensional plane.
4 . The method of claim 3 , wherein the object is or relates to genomic fragments immobilized on an array.
5 . The method of claim 1 , wherein the detection apparatus includes at least one camera.
6 . The method of claim 1 , wherein the parameter data relates to at least one of a grid orientation angle, an apparent pitch in pixel units, and a phase of a feature grid at a fixed pixel location of the image.
7 . The method of claim 1 , wherein quantifying the signal level of each feature comprises building a model of the subimage incorporating known feature locations and corresponding unknown intensities and fitting the model to the image of the object.
8 . The method of claim 7 wherein the model of the subimage comprises a matrix that is pre-computed and stored in computer memory or a computer-readable medium.
9 . The method of claim 8 , wherein the matrix is reused for a different subimage.
10 . The method of claim 1 , wherein each index address is a unique address.
11 . The method of claim 8 , wherein each unique address is an integer vector of length 2.
12 . The method of claim 1 , further comprising performing a chromatic correction of the image or image-related data.
13 . The method of claim 1 , wherein the detection apparatus comprises at least two cameras including a first camera and a second camera and wherein each of the first camera and the second camera is configured to obtain an image of two different color channels.
14 . The method of claim 1 , wherein each color channel coincides with a different label used to distinguish one nucleotide base type from another nucleotide base type.
15 . The method of claim 13 , wherein the first camera collects an image of first and second fluorescent channels and the second camera collects an image of third and fourth fluorescent channels.
16 . The method of claim 15 , further comprising performing a chromatic correction in order to associate feature images in the channels of a common camera.
17 . A non-transitory computer-readable medium containing instructions to configure a processor to perform operations comprising:
obtaining an image of the object using a detection apparatus, wherein the image includes a repeating pattern of features having different signal levels;
providing the image or image-related data to a computer, wherein the computer has parameter data that describe the repeating pattern of features;
partitioning the image or the image-related data into a plurality of registration subimages on the computer;
detecting on the computer the repeating pattern of features for each registration subimage;
assigning an index address for each feature of the repeating pattern of features;
matching the index address for each feature on the computer; and
quantifying a signal level of each feature.
18 . A system comprising:
a processor; and
a memory, wherein the processor and the memory are configured to perform operations comprising:
obtaining a camera image of the object using a detection apparatus, wherein the camera image includes a repeating pattern of features having different signal levels;
providing the camera image or image-related data to a computer, wherein the computer has parameter data that describe the repeating pattern of features;
partitioning the camera image or the image-related data into a plurality of registration subimages on the computer;
detecting on the computer the repeating pattern of features for each registration subimage;
assigning an index address for each feature of the repeating pattern of features;
matching the index address for each feature on the computer; and
quantifying a signal level of each feature.
19 . The system of claim 18 , the operations further comprising:
forming a corrugation image having substantially same dimensions as the camera image, the corrugation image related to three spatial frequencies.
20 . The system of claim 19 , wherein the three spatial frequencies describe a hex pattern.
21 . The system of claim 19 , wherein the three spatial frequencies relate to vectors each separated by 120 degrees.
22 . The system of claim 19 , further comprising correlating the camera image with the corrugation image to define a complex correlation image.
23 . The system of claim 22 , further comprising calculating a wrapped phase difference to a phase difference image.
24 . The system of claim 23 , further comprising unwrapping the phase difference image.
25 . The system of claim 24 , wherein areas having low correlation are not unmasked.
26 . The system of claim 24 , further comprising fitting the phase difference image to a polynomial.
27 . The system of claim 26 , wherein the polynomial is a Legendre polynomial.
28 . The system of claim 27 , further comprising computing grid locations that correspond to features in the phase difference image.
29 . The system of claim 28 , further comprising deconvoluting optical blurring of the image.