//来自插件 在缩放图片的同时能平滑处理 避免锯齿 var scaleImgAA; //AA: Antialias抗锯齿 function t(t, a, i, r) { function h() { B = "object" == typeof i ? i : a.src || r ? u : document.createElement("canvas"), B.width = s, B.height = f, G = B.getContext("2d") } function n(t) { if (t) { var e, a = G.getImageData(0, 0, s, f), i = a.data; for (e = 0; at > e; e += 4) i[e] = t[e] * it | 0, i[e + 1] = t[e + 1] * it | 0, i[e + 2] = t[e + 2] * it | 0, i[e + 3] = t[e + 3] * it | 0; /* return delete t, a */ return a } return G.getImageData(0, 0, s, f) } function o(t, e, a, i, r) { return .5 * (i - e + (2 * e - 5 * a + 4 * i - r + (3 * (a - i) + r - e) * t) * t) * t + a } a || (a = t.input, i = t.output, r = t.inputRemovable, t.scale && (t = t.scale)); var u, d; if (a.src) if (u = document.createElement("canvas"), null != a.naturalWidth) u.width = a.naturalWidth, u.height = a.naturalHeight; else if (null != a.runtimeStyle) { var l = a.runtimeStyle , c = l.width , g = l.height; l.width = "auto", l.height = "auto", u.width = a.width, u.height = a.height, l.width = c, l.height = g } else { var c = a.width , g = a.height; a.removeAttribute && (a.removeAttribute("width"), a.removeAttribute("height")), u.width = a.width, u.height = a.height, a.width = c, a.height = g } else u = a; d = u.getContext("2d"), a.src && d.drawImage(a, 0, 0); var s, f, m = u.width, w = u.height, p = d.getImageData(0, 0, m, w).data; if (!m || !w) return !1; (a.src || r) && u.clearRect(0, 0, m, w), "object" == typeof t ? t.width ? (s = t.width + .5 | 0, f = t.height + .5 | 0) : (s = m * t.scaleX + .5 | 0, f = w * t.scaleY + .5 | 0) : (s = t * m + .5 | 0, f = t * w + .5 | 0); var v, b, y, x, D, I, A, j, R, k, C, E, F, L, S, U, W, H, alpha, X, Y, q, z, B, G, J, K, M, N, O, P, Q, T, V, Z, $ = s << 2, _ = m << 2, tt = 0, et = 0, at = $ * f, it = 255.99 / 255, rt = s / m, ht = f / w, nt = rt * ht; if (rt > 1 || ht > 1) for (h(), J = n(), K = J.data, x = 0; f > x; x++) for (b = x / ht, R = 0 | b, q = b - R, N = R * _, M = 1 > R ? N : N - _, w - 2 > R ? (O = N + _, P = (R + 2) * _) : O = P = R > w - 2 ? N : N + _, y = 0; s > y; y++ , et += 4) v = y / rt, j = 0 | v, z = v - j, T = j << 2, Q = 1 > j ? T : T - 4, m - 2 > j ? (V = T + 4, Z = T + 8) : V = Z = j > m - 2 ? T : T + 4, H = o(q, o(z, p[M + Q], p[M + T], p[M + V], p[M + Z]), o(z, p[N + Q], p[N + T], p[N + V], p[N + Z]), o(z, p[O + Q], p[O + T], p[O + V], p[O + Z]), o(z, p[P + Q], p[P + T], p[P + V], p[P + Z])) * it | 0, ++Q, ++T, ++V, ++Z, X = o(q, o(z, p[M + Q], p[M + T], p[M + V], p[M + Z]), o(z, p[N + Q], p[N + T], p[N + V], p[N + Z]), o(z, p[O + Q], p[O + T], p[O + V], p[O + Z]), o(z, p[P + Q], p[P + T], p[P + V], p[P + Z])) * it | 0, ++Q, ++T, ++V, ++Z, Y = o(q, o(z, p[M + Q], p[M + T], p[M + V], p[M + Z]), o(z, p[N + Q], p[N + T], p[N + V], p[N + Z]), o(z, p[O + Q], p[O + T], p[O + V], p[O + Z]), o(z, p[P + Q], p[P + T], p[P + V], p[P + Z])) * it | 0, ++Q, ++T, ++V, ++Z, alpha = o(q, o(z, p[M + Q], p[M + T], p[M + V], p[M + Z]), o(z, p[N + Q], p[N + T], p[N + V], p[N + Z]), o(z, p[O + Q], p[O + T], p[O + V], p[O + Z]), o(z, p[P + Q], p[P + T], p[P + V], p[P + Z])) * it | 0, K[et] = H >= 0 ? 256 > H ? H : 255 : 0, K[et + 1] = X >= 0 ? 256 > X ? X : 255 : 0, K[et + 2] = Y >= 0 ? 256 > Y ? Y : 255 : 0, K[et + 3] = alpha >= 0 ? 256 > alpha ? alpha : 255 : 0; else { if (e.Float32Array) W = new Float32Array(at); else for (W = [], et = 0; at > et; ++et) W[et] = 0; for (b = 0; w > b; b++) for (x = b * ht, A = 0 | x, D = A * $, U = !!((A - (x + ht | 0)) * (w - 1 - b)) << 1, U && (F = A + 1 - x, L = x + ht - A - 1), v = 0; m > v; v++ , tt += 4) switch (y = v * rt, I = 0 | y, et = D + (I << 2), S = !!((I - (y + rt | 0)) * (m - 1 - v)), S && (C = I + 1 - y, E = y + rt - I - 1), H = p[tt], X = p[tt + 1], Y = p[tt + 2], alpha = p[tt + 3], S + U) { case 0: W[et] += H * nt, W[et + 1] += X * nt, W[et + 2] += Y * nt, W[et + 3] += alpha * nt; break; case 1: k = C * ht, W[et] += H * k, W[et + 1] += X * k, W[et + 2] += Y * k, W[et + 3] += alpha * k, k = E * ht, W[et + 4] += H * k, W[et + 5] += X * k, W[et + 6] += Y * k, W[et + 7] += alpha * k; break; case 2: k = rt * F, W[et] += H * k, W[et + 1] += X * k, W[et + 2] += Y * k, W[et + 3] += alpha * k, k = rt * L, et += $, W[et] += H * k, W[et + 1] += X * k, W[et + 2] += Y * k, W[et + 3] += alpha * k; break; default: k = C * F, W[et] += H * k, W[et + 1] += X * k, W[et + 2] += Y * k, W[et + 3] += alpha * k, k = E * F, W[et + 4] += H * k, W[et + 5] += X * k, W[et + 6] += Y * k, W[et + 7] += alpha * k, k = C * L, et += $, W[et] += H * k, W[et + 1] += X * k, W[et + 2] += Y * k, W[et + 3] += alpha * k, k = E * L, W[et + 4] += H * k, W[et + 5] += X * k, W[et + 6] += Y * k, W[et + 7] += alpha * k; } //delete p, h(), J = n(W) } if (G.putImageData(J, 0, 0), "string" == typeof i) { if ("png" === i || "jpeg" === i) { var ot; return ot = r && a.src ? a : new Image, ot.width = s, ot.height = f, ot.src = B.toDataURL("image/" + i, 0.85), ot } if ("png-src" === i || "jpeg-src" === i) return B.toDataURL("image/" + i.split("-")[0], 0.85) } return B } var e = window;//this; /* "undefined" != typeof exports ? ("undefined" != typeof module && module.exports && (exports = module.exports = t), exports.scale = t) : c = t */ scaleImgAA = t; export default scaleImgAA