西瓜视频地址解析

json解析工具：https://www.json.cn/

base64解析工具：https://www.sojson.com/base64.html

1.先获取videoid

2.通过videoid获取下载url请求链接

function crc32(video_id) {
        var n = function() {
            for (var t = 0,
            e = new Array(256), n = 0; 256 != n; ++n) t = n,
            t = 1 & t ? -306674912 ^ t >>> 1 : t >>> 1,
            t = 1 & t ? -306674912 ^ t >>> 1 : t >>> 1,
            t = 1 & t ? -306674912 ^ t >>> 1 : t >>> 1,
            t = 1 & t ? -306674912 ^ t >>> 1 : t >>> 1,
            t = 1 & t ? -306674912 ^ t >>> 1 : t >>> 1,
            t = 1 & t ? -306674912 ^ t >>> 1 : t >>> 1,
            t = 1 & t ? -306674912 ^ t >>> 1 : t >>> 1,
            t = 1 & t ? -306674912 ^ t >>> 1 : t >>> 1,
            e[n] = t;
            return "undefined" != typeof Int32Array ? new Int32Array(e) : e
        } (),
        o = function(t) {
            for (var e, o, r = -1,
            i = 0,
            a = t.length; i < a;) e = t.charCodeAt(i++),
            e < 128 ? r = r >>> 8 ^ n[255 & (r ^ e)] : e < 2048 ? (r = r >>> 8 ^ n[255 & (r ^ (192 | e >> 6 & 31))], r = r >>> 8 ^ n[255 & (r ^ (128 | 63 & e))]) : e >= 55296 && e < 57344 ? (e = (1023 & e) + 64, o = 1023 & t.charCodeAt(i++), r = r >>> 8 ^ n[255 & (r ^ (240 | e >> 8 & 7))], r = r >>> 8 ^ n[255 & (r ^ (128 | e >> 2 & 63))], r = r >>> 8 ^ n[255 & (r ^ (128 | o >> 6 & 15 | (3 & e) << 4))], r = r >>> 8 ^ n[255 & (r ^ (128 | 63 & o))]) : (r = r >>> 8 ^ n[255 & (r ^ (224 | e >> 12 & 15))], r = r >>> 8 ^ n[255 & (r ^ (128 | e >> 6 & 63))], r = r >>> 8 ^ n[255 & (r ^ (128 | 63 & e))]);
            return r ^ -1
        },
        r = "/video/urls/v/1/toutiao/mp4/"+video_id + "?r=" + Math.random().toString(10).substring(2);
        "/" != r[0] && (r = "/" + r);
        var i = o(r) >>> 0;
        return ("https://ib.365yg.com"+r + "&s=" + i)
    }
var url = crc32(video_id);

　　3.get请求上面的地址，返回的JSON找到main_url,对其base64解密得到下载地址