index.js

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
function dim(x) {
    var y;
    if (typeof x === 'object') {
        y = x[0];
        if (typeof y === 'object') {
            return [x.length, y.length];
        }
        return [x.length];
    }
    return [];
}
function _foreach2(x, s, k, f) {
    if (k === s.length - 1) {
        return f(x);
    }
    var i;
    var n = s[k];
    var ret = Array(n);
    for (i = n - 1; i >= 0; i--) {
        ret[i] = _foreach2(x[i], s, k + 1, f);
    }
    return ret;
}
function cloneV(x) {
    var _n = x.length;
    var i;
    var ret = Array(_n);
    for (i = _n - 1; i !== -1; --i) {
        ret[i] = x[i];
    }
    return ret;
}
function clone(x) {
    if (typeof x !== 'object')
        return x;
    var V = cloneV;
    var s = dim(x);
    return _foreach2(x, s, 0, V);
}
function diag(d) {
    var i;
    var i1;
    var j;
    var n = d.length;
    var A = Array(n);
    var Ai;
    for (i = n - 1; i >= 0; i--) {
        Ai = Array(n);
        i1 = i + 2;
        for (j = n - 1; j >= i1; j -= 2) {
            Ai[j] = 0;
            Ai[j - 1] = 0;
        }
        if (j > i) {
            Ai[j] = 0;
        }
        Ai[i] = d[i];
        for (j = i - 1; j >= 1; j -= 2) {
            Ai[j] = 0;
            Ai[j - 1] = 0;
        }
        if (j === 0) {
            Ai[0] = 0;
        }
        A[i] = Ai;
    }
    return A;
}
function rep(s, v, k) {
    if (typeof k === 'undefined') {
        k = 0;
    }
    var n = s[k];
    var ret = Array(n);
    var i;
    if (k === s.length - 1) {
        for (i = n - 2; i >= 0; i -= 2) {
            ret[i + 1] = v;
            ret[i] = v;
        }
        if (i === -1) {
            ret[0] = v;
        }
        return ret;
    }
    for (i = n - 1; i >= 0; i--) {
        ret[i] = rep(s, v, k + 1);
    }
    return ret;
}
function identity(n) {
    return diag(rep([n], 1));
}
function inv(a) {
    var s = dim(a);
    var abs = Math.abs;
    var m = s[0];
    var n = s[1];
    var A = clone(a);
    var Ai;
    var Aj;
    var I = identity(m);
    var Ii;
    var Ij;
    var i, j, k, x;
    for (j = 0; j < n; ++j) {
        var i0 = -1;
        var v0 = -1;
        for (i = j; i !== m; ++i) {
            k = abs(A[i][j]);
            if (k > v0) {
                i0 = i;
                v0 = k;
            }
        }
        Aj = A[i0];
        A[i0] = A[j];
        A[j] = Aj;
        Ij = I[i0];
        I[i0] = I[j];
        I[j] = Ij;
        x = Aj[j];
        for (k = j; k !== n; ++k)
            Aj[k] /= x;
        for (k = n - 1; k !== -1; --k)
            Ij[k] /= x;
        for (i = m - 1; i !== -1; --i) {
            if (i !== j) {
                Ai = A[i];
                Ii = I[i];
                x = Ai[j];
                for (k = j + 1; k !== n; ++k)
                    Ai[k] -= Aj[k] * x;
                for (k = n - 1; k > 0; --k) {
                    Ii[k] -= Ij[k] * x;
                    --k;
                    Ii[k] -= Ij[k] * x;
                }
                if (k === 0)
                    Ii[0] -= Ij[0] * x;
            }
        }
    }
    return I;
}
function dotMMsmall(x, y) {
    var i, j, k, p, q, r, ret, foo, bar, woo, i0;
    p = x.length;
    q = y.length;
    r = y[0].length;
    ret = Array(p);
    for (i = p - 1; i >= 0; i--) {
        foo = Array(r);
        bar = x[i];
        for (k = r - 1; k >= 0; k--) {
            woo = bar[q - 1] * y[q - 1][k];
            for (j = q - 2; j >= 1; j -= 2) {
                i0 = j - 1;
                woo += bar[j] * y[j][k] + bar[i0] * y[i0][k];
            }
            if (j === 0) {
                woo += bar[0] * y[0][k];
            }
            foo[k] = woo;
        }
        ret[i] = foo;
    }
    return ret;
}
function dotMV(x, y) {
    var p = x.length;
    var i;
    var ret = Array(p);
    for (i = p - 1; i >= 0; i--) {
        ret[i] = dotVV(x[i], y);
    }
    return ret;
}
function dotVV(x, y) {
    var i;
    var n = x.length;
    var i1;
    var ret = x[n - 1] * y[n - 1];
    for (i = n - 2; i >= 1; i -= 2) {
        i1 = i - 1;
        ret += x[i] * y[i] + x[i1] * y[i1];
    }
    if (i === 0) {
        ret += x[0] * y[0];
    }
    return ret;
}
function transpose(x) {
    var i;
    var j;
    var m = x.length;
    var n = x[0].length;
    var ret = Array(n);
    var A0;
    var A1;
    var Bj;
    for (j = 0; j < n; j++)
        ret[j] = Array(m);
    for (i = m - 1; i >= 1; i -= 2) {
        A1 = x[i];
        A0 = x[i - 1];
        for (j = n - 1; j >= 1; --j) {
            Bj = ret[j];
            Bj[i] = A1[j];
            Bj[i - 1] = A0[j];
            --j;
            Bj = ret[j];
            Bj[i] = A1[j];
            Bj[i - 1] = A0[j];
        }
        if (j === 0) {
            Bj = ret[0];
            Bj[i] = A1[0];
            Bj[i - 1] = A0[0];
        }
    }
    if (i === 0) {
        A0 = x[0];
        for (j = n - 1; j >= 1; --j) {
            ret[j][0] = A0[j];
            --j;
            ret[j][0] = A0[j];
        }
        if (j === 0) {
            ret[0][0] = A0[0];
        }
    }
    return ret;
}
function round(num) {
    return Math.round(num * 10000000000) / 10000000000;
}
function getNormalizationCoefficients(srcPts, dstPts, isInverse) {
    if (isInverse) {
        var tmp = dstPts;
        dstPts = srcPts;
        srcPts = tmp;
    }
    var r1 = [
        srcPts[0],
        srcPts[1],
        1,
        0,
        0,
        0,
        -1 * dstPts[0] * srcPts[0],
        -1 * dstPts[0] * srcPts[1],
    ];
    var r2 = [
        0,
        0,
        0,
        srcPts[0],
        srcPts[1],
        1,
        -1 * dstPts[1] * srcPts[0],
        -1 * dstPts[1] * srcPts[1],
    ];
    var r3 = [
        srcPts[2],
        srcPts[3],
        1,
        0,
        0,
        0,
        -1 * dstPts[2] * srcPts[2],
        -1 * dstPts[2] * srcPts[3],
    ];
    var r4 = [
        0,
        0,
        0,
        srcPts[2],
        srcPts[3],
        1,
        -1 * dstPts[3] * srcPts[2],
        -1 * dstPts[3] * srcPts[3],
    ];
    var r5 = [
        srcPts[4],
        srcPts[5],
        1,
        0,
        0,
        0,
        -1 * dstPts[4] * srcPts[4],
        -1 * dstPts[4] * srcPts[5],
    ];
    var r6 = [
        0,
        0,
        0,
        srcPts[4],
        srcPts[5],
        1,
        -1 * dstPts[5] * srcPts[4],
        -1 * dstPts[5] * srcPts[5],
    ];
    var r7 = [
        srcPts[6],
        srcPts[7],
        1,
        0,
        0,
        0,
        -1 * dstPts[6] * srcPts[6],
        -1 * dstPts[6] * srcPts[7],
    ];
    var r8 = [
        0,
        0,
        0,
        srcPts[6],
        srcPts[7],
        1,
        -1 * dstPts[7] * srcPts[6],
        -1 * dstPts[7] * srcPts[7],
    ];
    var matA = [r1, r2, r3, r4, r5, r6, r7, r8];
    var matB = dstPts;
    var matC;
    try {
        matC = inv(dotMMsmall(transpose(matA), matA));
    }
    catch (e) {
        return [1, 0, 0, 0, 1, 0, 0, 0];
    }
    var matD = dotMMsmall(matC, transpose(matA));
    var matX = dotMV(matD, matB);
    for (var i = 0; i < matX.length; i++) {
        matX[i] = round(matX[i]);
    }
    matX[8] = 1;
    return matX;
}
function applyTransform(coeffs, x, y) {
    var coordinates = [];
    coordinates[0] =
        (coeffs[0] * x + coeffs[1] * y + coeffs[2]) /
            (coeffs[6] * x + coeffs[7] * y + 1);
    coordinates[1] =
        (coeffs[3] * x + coeffs[4] * y + coeffs[5]) /
            (coeffs[6] * x + coeffs[7] * y + 1);
    return coordinates;
}
function fixPerspective(srcPts, dstPts) {
    var coeffs = getNormalizationCoefficients(srcPts, dstPts, false);
    return function (x, y) { return applyTransform(coeffs, x, y); };
}
exports.default = fixPerspective;