问题
I'm attempting to use opencv.js to align images to a baseline image. I'm following some basic python guidance that i've seen work (example: https://alexanderpacha.com/2018/01/29/aligning-images-an-engineers-solution/)
but i'm getting tripped up with an error that I don't quite understand. The error is "opencv.js:30 Uncaught TypeError: Cannot use 'in' operator to search for 'type' in 1e-10" and it seems to be caused by the "criteria" variable passed to "cv.findTransformECC();" see here.
any guidance as to what I'm doing wrong here?
function Align_img(){
let image_baseline = cv.imread(imgElement_Baseline);
let image = cv.imread('imageChangeup');
let im1_gray = new cv.Mat();
let im2_gray = new cv.Mat();
let im2_aligned = new cv.Mat();
//get size of baseline image
width1 = image_baseline.cols;
height1 = image_baseline.rows;
//resize image to baseline image
let dim1 = new cv.Size(width1, height1);
cv.resize(image, image, dim1, cv.INTER_AREA);
// Convert images to grayscale
cv.cvtColor(image_baseline, im1_gray, cv.COLOR_BGR2GRAY);
cv.cvtColor(image, im2_gray, cv.COLOR_BGR2GRAY);
// Find size of image1
let dsize = new cv.Size(image_baseline.rows, image_baseline.cols);
// Define the motion model
warp_mode = cv.MOTION_HOMOGRAPHY;
// Define 3x3 matrix and initialize the matrix to identity
let warp_matrix = cv.Mat.eye(3, 3, cv.CV_8U);
// Specify the number of iterations.
number_of_iterations = 5000;
// Specify the threshold of the increment in the correlation coefficient between two iterations
termination_eps = 0.0000000001; //1e-10;
// Define termination criteria
criteria = (cv.TERM_CRITERIA_EPS | cv.TERM_CRITERIA_COUNT, number_of_iterations, termination_eps);
//Run the ECC algorithm. The results are stored in warp_matrix.
cv.findTransformECC(im1_gray, im2_gray, warp_matrix, warp_mode, criteria, null, 5);
// Use warpPerspective for Homography
cv.warpPerspective (image, im2_aligned, warp_matrix, dsize, cv.INTER_LINEAR + cv.WARP_INVERSE_MAP);
cv.imshow('imageChangeup', im2_aligned);
im1_gray.delete();
im2_gray.delete();
im2_aligned.delete();
};
UPDATE: 2 things. 1. Found easy fix to error (code below) and 2. looks like a bug in the findTransformECC opencv.js API causing this method not to work. Here is current code.
The API has 2 optional parameters (inputMask and gaussFiltSize) but if you don't include them you get an error ("function findTransformECC called with 5 arguments, expected 7 args!").
The issue is what to use for inputMask - "null" does not work, there doesn't seem to be support for 'cv.noArray()' and I can't find a mask that doesn't lead to a 'uncaught exception' error.
I'll update again once I find a workaround. Let me know if anyone sees a work around.
function Align_img(){
let image_baseline = cv.imread(imgElement_Baseline);
let image = cv.imread('imageChangeup');
let im1_gray = new cv.Mat();
let im2_gray = new cv.Mat();
let im2_aligned = new cv.Mat();
//get size of baseline image
var width1 = image_baseline.cols;
var height1 = image_baseline.rows;
//resize image to baseline image
let dim1 = new cv.Size(width1, height1);
cv.resize(image, image, dim1, cv.INTER_AREA);
// Convert images to grayscale
cv.cvtColor(image_baseline, im1_gray, cv.COLOR_BGR2GRAY);
cv.cvtColor(image, im2_gray, cv.COLOR_BGR2GRAY);
// Find size of image1
let dsize = new cv.Size(image_baseline.rows, image_baseline.cols);
// Define the motion model
const warp_mode = cv.MOTION_HOMOGRAPHY;
// Define 3x3 matrix and initialize the matrix to identity
let warp_matrix = cv.Mat.eye(3, 3, cv.CV_8U);
// Specify the number of iterations.
const number_of_iterations = 5000;
// Specify the threshold of the increment in the correlation coefficient between two iterations
const termination_eps = 0.0000000001; //1e-10;
// Define termination criteria
//const criteria = (cv.TERM_CRITERIA_EPS | cv.TERM_CRITERIA_COUNT, number_of_iterations, termination_eps);
let criteria = new cv.TermCriteria(cv.TERM_CRITERIA_EPS | cv.TERM_CRITERIA_COUNT, number_of_iterations, termination_eps);
//Run the ECC algorithm. The results are stored in warp_matrix.
//let inputMask = new cv.Mat.ones(im1_gray.size(), cv.CV_8U); //uint8
cv.findTransformECC(im1_gray, im2_gray, warp_matrix, warp_mode, criteria, null, 5);
// Use warpPerspective for Homography
cv.warpPerspective (image, im2_aligned, warp_matrix, dsize, cv.INTER_LINEAR + cv.WARP_INVERSE_MAP);
getMatStats(im2_aligned, 1); //0 = baseline (srcMat), 1 = image (srcMat_compare)
cv.imshow('imageChangeup', im2_aligned);
im1_gray.delete();
im2_gray.delete();
im2_aligned.delete();
};
UPDATE 2 I verified code works fine in Python. code below. The issue at hand now is simply, how do you this in Javascript: "inputMask=None"
Python:
# Read the images to be aligned
im1 = cv2.imread(r"C:\temp\tcoin\69.jpg");
im2 = cv2.imread(r"C:\temp\tcoin\pic96_crop.jpg");
#resize image to compare
width1 = int(im1.shape[1])
height1 = int(im1.shape[0])
dim1 = (width1, height1)
im2 = cv2.resize(im2, dim1, interpolation = cv2.INTER_AREA)
# Convert images to grayscale
im1_gray = cv2.cvtColor(im1,cv2.COLOR_BGR2GRAY)
im2_gray = cv2.cvtColor(im2,cv2.COLOR_BGR2GRAY)
# Find size of image1
sz = im1.shape
# Define the motion model
warp_mode = cv2.MOTION_HOMOGRAPHY
# Define 2x3 or 3x3 matrices and initialize the matrix to identity
warp_matrix = np.eye(3, 3, dtype=np.float32)
# Specify the number of iterations.
number_of_iterations = 5000;
# Specify the threshold of the increment
# in the correlation coefficient between two iterations
termination_eps = 1e-10;
# Define termination criteria
criteria = (cv2.TERM_CRITERIA_EPS | cv2.TERM_CRITERIA_COUNT, number_of_iterations, termination_eps)
# Run the ECC algorithm. The results are stored in warp_matrix.
(cc, warp_matrix) = cv2.findTransformECC (im1_gray,im2_gray,warp_matrix, warp_mode, criteria, inputMask=None, gaussFiltSize=1)
# Use warpPerspective for Homography
im2_aligned = cv2.warpPerspective (im2, warp_matrix, (sz[1],sz[0]), flags=cv2.INTER_LINEAR + cv2.WARP_INVERSE_MAP)
# Show final results
cv2.imshow("Aligned Image 2", im2_aligned)
cv2.imwrite(r"c:\temp\tcoin\output\pic96_cropB.jpg", im2_aligned)
cv2.waitKey(0)
来源：https://stackoverflow.com/questions/62744310/opencv-js-issue-with-findtransformecc-criteria