从data_URL读取图像详细信息(GPS long lat)

时间:2014-12-22 05:33:12

标签: c# cordova android-camera exif exiflib

我使用cordova phonegap api打开相机

        $scope.capturePhoto = function () {
        navigator.camera.getPicture(onPhotoDataSuccess, onFail, {quality: 50,
                destinationType: navigator.camera.DestinationType.DATA_URL, sourceType: 1});
        }
        $scope.capturePhotoEdit = function () {
            navigator.camera.getPicture(onPhotoDataSuccess, onFail, {quality: 20, allowEdit: true,
                destinationType: navigator.camera.DestinationType.DATA_URL, sourceType: 1});
        }
        $scope.getPhoto = function () {
            navigator.camera.getPicture(onPhotoDataSuccess, onFail, {quality: 50,
                destinationType: navigator.camera.DestinationType.DATA_URL, sourceType: 0});
        }
        $scope.getPhotoAlbum = function () {
            navigator.camera.getPicture(onPhotoDataSuccess, onFail, {quality: 50,
                destinationType: navigator.camera.DestinationType.DATA_URL, sourceType: 2});
        }
        onFail = function (message) {
            $window.alert(message);
        } 

在DATA_URL长字符串中,如base64,但在C#

中exif不能读取图像详细信息

如果我使用文件上传并转换为base64,那么很容易在C#中获取Exif详细信息(GPS Long Lat),但不能打开带有File uploader标签的相机:

 function readImage(input) {
    console.log(input);
        if ( input.files && input.files[0] ) {
           var FR= new FileReader();
           FR.onload = function(e) {
            // $('#img').attr( "src", e.target.result );
             $('#base').text( e.target.result );
           };       
         FR.readAsDataURL( input.files[0] );
       }
    }

   $("#asd").change(function(){
         readImage( this );
   });

在c#代码中读取Exif详细信息:

using ExifLibrary;

byte[] data = Convert.FromBase64String(model.imagebase64);
            string file = model.workId + "_" + SnapName + ".Jpeg";
            string liveserverpath =        ConfigurationManager.AppSettings["MyFileLocation"].ToString();
            liveserverpath = liveserverpath + file;
            var exif = ExifFile.Read(liveserverpath);
            try
            {
                newmodel.P_Latitude = (exif.Properties[ExifTag.GPSLatitude]).ToString();
                newmodel.P_Longitude = (exif.Properties[ExifTag.GPSLongitude]).ToString();
                newmodel.Snap_Status = "Valid";
            }

我的问题是:为什么Data_URL(字符串)中的图像细节丢失,而文件上传图像中的图像细节容易读取图像细节(GPS long lat)

请让我知道,帮助我,我花了一个星期但没有从data_URL获得任何exif图像细节,

1 个答案:

答案 0 :(得分:0)

这是2.6.0之前的Cordova版本中的known issue。如果您确定使用的是最新版本的Cordova,那么您应该没问题。