小米手机拍照能打出来本地路径，但是base64 不出结果，相册选取正常。并且调用相机时很卡顿，

getImage() {
var that = this;
var cmr = plus.camera.getCamera();
var res = cmr.supportedImageResolutions[0];
var fmt = cmr.supportedImageFormats[0];
cmr.captureImage(function(p) {
plus.io.resolveLocalFileSystemURL(
p,
function(entry) {
var tmpPath = entry.toLocalURL(); //获取目录路径转换为本地路径URL
that.fileSrc = tmpPath;
entry.file(function(file) {
var fileReader = new plus.io.FileReader();
// 本地文件转base64
fileReader.readAsDataURL(file)
fileReader.onloadend = function(e) {
//获取文件base64 ！！！！！
let base64URL = e.target.result.toString();
let src = base64URL;
let str=that.base64toFile(src,file.name);
let formData = new FormData();
formData.append("file", str);
that.Upload(formData);
}
});
},
function(e) {
Toast('读取拍照文件错误:' + error.message)
}, {
resolution: res,
format: fmt
}
);
},
function(error) {
alert("Capture image failed: " + error.message);
}, {
//resolution: res,
//ormat: fmt
//filter: "image"
filename: "_doc/camera/",
filter: "image"
}
);