diff --git a/core/Common.php b/core/Common.php
index 823e884af1701d6cf62e11b9f5df54bfbbd7d290..a3e7515a247bd249e0d239b4827ba82dc6c885fe 100644
--- a/core/Common.php
+++ b/core/Common.php
@@ -462,7 +462,7 @@ class Common
         // we deal w/ json differently
         if ($varType == 'json') {
             $value = self::undoMagicQuotes($requestArrayToUse[$varName]);
-            $value = self::json_decode($value, $assoc = true);
+            $value = json_decode($value, $assoc = true);
             return self::sanitizeInputValues($value, $alreadyStripslashed = true);
         }
 
diff --git a/core/Plugin/MetadataLoader.php b/core/Plugin/MetadataLoader.php
index 34bb90dcdcf021a3dc85721939d3e0949d89bcbc..e75bc583383880f8f8d152a912abd049808ab154 100644
--- a/core/Plugin/MetadataLoader.php
+++ b/core/Plugin/MetadataLoader.php
@@ -95,7 +95,7 @@ class MetadataLoader
             return array();
         }
 
-        $info = Common::json_decode($json, $assoc = true);
+        $info = json_decode($json, $assoc = true);
         if (!is_array($info)
             || empty($info)
         ) {
diff --git a/core/Tracker.php b/core/Tracker.php
index 38467fc65d4d7ed5776b8db3ae98ea11830aedb6..a84afd96326d3117220222dad542a4c0124a9504 100644
--- a/core/Tracker.php
+++ b/core/Tracker.php
@@ -436,7 +436,7 @@ class Tracker
                 $result['message'] = $this->getMessageFromException($e);
             }
             Common::sendHeader('Content-Type: application/json');
-            echo Common::json_encode($result);
+            echo json_encode($result);
             die(1);
             exit;
         }
@@ -496,7 +496,7 @@ class Tracker
             $this->outputAccessControlHeaders();
 
             Common::sendHeader('Content-Type: application/json');
-            echo Common::json_encode($result);
+            echo json_encode($result);
             exit;
         }
         switch ($this->getState()) {
diff --git a/core/Translate.php b/core/Translate.php
index 65381c0a2da811ec4d1144c1c275dfd3484b5a36..c29d0f0339f317ebd9c20299e90dd332131b094a 100644
--- a/core/Translate.php
+++ b/core/Translate.php
@@ -173,7 +173,7 @@ class Translate
             $clientSideTranslations[$key] = $translations[$plugin][$stringName];
         }
 
-        $js = 'var translations = ' . Common::json_encode($clientSideTranslations) . ';';
+        $js = 'var translations = ' . json_encode($clientSideTranslations) . ';';
         $js .= "\n" . 'if (typeof(piwik_translations) == \'undefined\') { var piwik_translations = new Object; }' .
             'for(var i in translations) { piwik_translations[i] = translations[i];} ';
         return $js;
diff --git a/core/Updates/1.8.3-b1.php b/core/Updates/1.8.3-b1.php
index 7a00ec20b3f890b574cd14ceb8498266c4968fba..ee8e6c4d0057951661bd166b87b90e59fc2ba198 100644
--- a/core/Updates/1.8.3-b1.php
+++ b/core/Updates/1.8.3-b1.php
@@ -98,8 +98,8 @@ class Updates_1_8_3_b1 extends Updates
                          is_null($period) ? ScheduledReports::DEFAULT_PERIOD : $period,
                          ScheduledReports::EMAIL_TYPE,
                          is_null($format) ? ScheduledReports::DEFAULT_REPORT_FORMAT : $format,
-                         Common::json_encode(preg_split('/,/', $reports)),
-                         Common::json_encode($parameters),
+                         json_encode(preg_split('/,/', $reports)),
+                         json_encode($parameters),
                          $ts_created,
                          $ts_last_sent,
                          $deleted
diff --git a/plugins/CustomVariables/Archiver.php b/plugins/CustomVariables/Archiver.php
index 47e1363dc4e3b52026887ad0e672addc59ce018d..704038b0a1bca8f24bbe13f5e3dc74363bc6afa2 100644
--- a/plugins/CustomVariables/Archiver.php
+++ b/plugins/CustomVariables/Archiver.php
@@ -154,7 +154,7 @@ class Archiver extends \Piwik\Plugin\Archiver
             if (substr($value, -2) != '"]') {
                 $value .= '"]';
             }
-            $decoded = @Common::json_decode($value);
+            $decoded = json_decode($value);
             if (is_array($decoded)) {
                 $count = 0;
                 foreach ($decoded as $category) {
diff --git a/plugins/Dashboard/Controller.php b/plugins/Dashboard/Controller.php
index c7a89a75a5d86d82634a1368c966e5963c627064..4c7d0c53f4fd33d24c56d164f58a1bc042288bb6 100644
--- a/plugins/Dashboard/Controller.php
+++ b/plugins/Dashboard/Controller.php
@@ -39,7 +39,7 @@ class Controller extends \Piwik\Plugin\Controller
         $view = new View($template);
         $this->setGeneralVariablesView($view);
 
-        $view->availableWidgets = Common::json_encode(WidgetsList::get());
+        $view->availableWidgets = json_encode(WidgetsList::get());
         $view->availableLayouts = $this->getAvailableLayouts();
 
         $view->dashboardId = Common::getRequestVar('idDashboard', 1, 'int');
@@ -75,7 +75,7 @@ class Controller extends \Piwik\Plugin\Controller
         $this->checkTokenInUrl();
 
         Json::sendHeaderJSON();
-        return Common::json_encode(WidgetsList::get());
+        return json_encode(WidgetsList::get());
     }
 
     public function getDashboardLayout($checkToken = true)
@@ -148,7 +148,7 @@ class Controller extends \Piwik\Plugin\Controller
         $dashboards = $this->dashboard->getAllDashboards($login);
 
         Json::sendHeaderJSON();
-        return Common::json_encode($dashboards);
+        return json_encode($dashboards);
     }
 
     /**
@@ -175,7 +175,7 @@ class Controller extends \Piwik\Plugin\Controller
         $nextId = $this->getModel()->createNewDashboardForUser($login, $name, $layout);
 
         Json::sendHeaderJSON();
-        return Common::json_encode($nextId);
+        return json_encode($nextId);
     }
 
     public function copyDashboardToUser()
@@ -197,7 +197,7 @@ class Controller extends \Piwik\Plugin\Controller
             $nextId = $this->getModel()->createNewDashboardForUser($user, $name, $layout);
 
             Json::sendHeaderJSON();
-            return Common::json_encode($nextId);
+            return json_encode($nextId);
         }
     }
 
diff --git a/plugins/Dashboard/Dashboard.php b/plugins/Dashboard/Dashboard.php
index 1ff5a98182fbc209f41164b169bb518005c9f257..a0a12985c3a87076599c88f85b9e6fc9e0131f2b 100644
--- a/plugins/Dashboard/Dashboard.php
+++ b/plugins/Dashboard/Dashboard.php
@@ -193,12 +193,12 @@ class Dashboard extends \Piwik\Plugin
         $layout = str_replace("\\\"", "\"", $layout);
         $layout = str_replace("\n", "", $layout);
 
-        return Common::json_decode($layout, $assoc = false);
+        return json_decode($layout, $assoc = false);
     }
 
     public function encodeLayout($layout)
     {
-        return Common::json_encode($layout);
+        return json_encode($layout);
     }
 
     public function getJsFiles(&$jsFiles)
diff --git a/plugins/Goals/Controller.php b/plugins/Goals/Controller.php
index e7af6d6243d4ccc2c6038499fd603afbee070200..3e61eb06e31f5908d0befa50264d245148b7c189 100644
--- a/plugins/Goals/Controller.php
+++ b/plugins/Goals/Controller.php
@@ -168,7 +168,7 @@ class Controller extends \Piwik\Plugin\Controller
                 $goal['pattern'] = Common::unsanitizeInputValue($goal['pattern']);
             }
         }
-        $view->goalsJSON = Common::json_encode($goals);
+        $view->goalsJSON = json_encode($goals);
 
         $view->userCanEditGoals = Piwik::isUserHasAdminAccess($this->idSite);
         $view->ecommerceEnabled = $this->site->isEcommerceEnabled();
diff --git a/plugins/MobileMessaging/API.php b/plugins/MobileMessaging/API.php
index c8268c76a72b77ca64cac7907573a0057228ce3e..aaf30e6a640136dbf7b931caacc0c64bdac9ba35 100644
--- a/plugins/MobileMessaging/API.php
+++ b/plugins/MobileMessaging/API.php
@@ -365,7 +365,7 @@ class API extends \Piwik\Plugin\API
     {
         Option::set(
             $user . MobileMessaging::USER_SETTINGS_POSTFIX_OPTION,
-            Common::json_encode($settings)
+            json_encode($settings)
         );
     }
 
@@ -392,7 +392,7 @@ class API extends \Piwik\Plugin\API
         if (empty($userSettings)) {
             $userSettings = array();
         } else {
-            $userSettings = Common::json_decode($userSettings, true);
+            $userSettings = json_decode($userSettings, true);
         }
 
         return $userSettings;
diff --git a/plugins/Overlay/Controller.php b/plugins/Overlay/Controller.php
index ea540c6e1482d5450b4d68b2618f49d7bc9712fc..7ddfde1e41366d3056e8671c3a3ee01766c8035d 100644
--- a/plugins/Overlay/Controller.php
+++ b/plugins/Overlay/Controller.php
@@ -160,7 +160,7 @@ class Controller extends \Piwik\Plugin\Controller
 					var urlToRedirect = window.location.hash.substr(1);
 					var urlToRedirectWithoutPrefix = removeUrlPrefix(urlToRedirect);
 
-					var knownUrls = ' . Common::json_encode($urls) . ';
+					var knownUrls = ' . json_encode($urls) . ';
 					for (var i = 0; i < knownUrls.length; i++) {
 						var testUrl = removeUrlPrefix(knownUrls[i]);
 						if (urlToRedirectWithoutPrefix.substr(0, testUrl.length) == testUrl) {
diff --git a/plugins/SEO/MajesticClient.php b/plugins/SEO/MajesticClient.php
index 50319582091519eccfcef865fa156db7189791c7..b7a7eeddc8509841484fc9190e21a74431f506b8 100644
--- a/plugins/SEO/MajesticClient.php
+++ b/plugins/SEO/MajesticClient.php
@@ -65,7 +65,7 @@ class MajesticClient
             'referrer_domains_count' => false
         );
 
-        $apiResponse = Common::json_decode($apiResponse, $assoc = true);
+        $apiResponse = json_decode($apiResponse, $assoc = true);
         if (!empty($apiResponse)
             && !empty($apiResponse['Data'])
         ) {
diff --git a/plugins/ScheduledReports/API.php b/plugins/ScheduledReports/API.php
index 66eb55a23503abeab47a651fcc7a487eb9675d10..e8a105114b8146c40488625b652e49dff84fcd4d 100644
--- a/plugins/ScheduledReports/API.php
+++ b/plugins/ScheduledReports/API.php
@@ -236,10 +236,10 @@ class API extends \Piwik\Plugin\API
 
         foreach ($reports as &$report) {
             // decode report parameters
-            $report['parameters'] = Common::json_decode($report['parameters'], true);
+            $report['parameters'] = json_decode($report['parameters'], true);
 
             // decode report list
-            $report['reports'] = Common::json_decode($report['reports'], true);
+            $report['reports'] = json_decode($report['reports'], true);
         }
 
         // static cache
@@ -294,7 +294,7 @@ class API extends \Piwik\Plugin\API
         }
 
         // override and/or validate report parameters
-        $report['parameters'] = Common::json_decode(
+        $report['parameters'] = json_decode(
             self::validateReportParameters($reportType, empty($parameters) ? $report['parameters'] : $parameters),
             true
         );
@@ -624,7 +624,7 @@ class API extends \Piwik\Plugin\API
          */
         Piwik::postEvent(self::VALIDATE_PARAMETERS_EVENT, array(&$parameters, $reportType));
 
-        return Common::json_encode($parameters);
+        return json_encode($parameters);
     }
 
     private static function validateAndTruncateDescription(&$description)
@@ -653,7 +653,7 @@ class API extends \Piwik\Plugin\API
             }
         }
 
-        return Common::json_encode($requestedReports);
+        return json_encode($requestedReports);
     }
 
     private static function validateCommonReportAttributes($period, $hour, &$description, &$idSegment, $reportType, $reportFormat)
diff --git a/plugins/ScheduledReports/Controller.php b/plugins/ScheduledReports/Controller.php
index 2bb64b8fafb73b438691c7bfbcb78849ae890a08..2ae16cc410f2a791a1594c1a12f4c38404dda1d2 100644
--- a/plugins/ScheduledReports/Controller.php
+++ b/plugins/ScheduledReports/Controller.php
@@ -66,7 +66,7 @@ class Controller extends \Piwik\Plugin\Controller
             }
         }
         $view->reports = $reports;
-        $view->reportsJSON = Common::json_encode($reportsById);
+        $view->reportsJSON = json_encode($reportsById);
 
         $view->downloadOutputType = API::OUTPUT_INLINE;
 
diff --git a/plugins/UserCountry/Controller.php b/plugins/UserCountry/Controller.php
index a6ed712dbe76658cf00eb2201becf6e323dd2d10..145f981cc34ffe2782814c722a1447ec36fbb697 100644
--- a/plugins/UserCountry/Controller.php
+++ b/plugins/UserCountry/Controller.php
@@ -135,9 +135,9 @@ class Controller extends \Piwik\Plugin\ControllerAdmin
                     $result['next_screen'] = $this->getGeoIpUpdaterManageScreen();
                 }
 
-                return Common::json_encode($result);
+                return json_encode($result);
             } catch (Exception $ex) {
-                return Common::json_encode(array('error' => $ex->getMessage()));
+                return json_encode(array('error' => $ex->getMessage()));
             }
         }
     }
@@ -207,15 +207,15 @@ class Controller extends \Piwik\Plugin\ControllerAdmin
                 // the browser so it can download it next
                 $info = $this->getNextMissingDbUrlInfo();
                 if ($info !== false) {
-                    return Common::json_encode($info);
+                    return json_encode($info);
                 } else {
                     $view = new View("@UserCountry/_updaterNextRunTime");
                     $view->nextRunTime = GeoIPAutoUpdater::getNextRunTime();
                     $nextRunTimeHtml = $view->render();
-                    return Common::json_encode(array('nextRunTime' => $nextRunTimeHtml));
+                    return json_encode(array('nextRunTime' => $nextRunTimeHtml));
                 }
             } catch (Exception $ex) {
-                return Common::json_encode(array('error' => $ex->getMessage()));
+                return json_encode(array('error' => $ex->getMessage()));
             }
         }
     }
@@ -270,13 +270,13 @@ class Controller extends \Piwik\Plugin\ControllerAdmin
 
                     $info = $this->getNextMissingDbUrlInfo();
                     if ($info !== false) {
-                        return Common::json_encode($info);
+                        return json_encode($info);
                     }
                 }
 
-                return Common::json_encode($result);
+                return json_encode($result);
             } catch (Exception $ex) {
-                return Common::json_encode(array('error' => $ex->getMessage()));
+                return json_encode(array('error' => $ex->getMessage()));
             }
         }
     }
diff --git a/plugins/UserCountryMap/Controller.php b/plugins/UserCountryMap/Controller.php
index e5f845d80a3fc3d886d517bb15a28ba900fb9d2c..914835439e13dd4f8a298efb73336263ca9be892 100644
--- a/plugins/UserCountryMap/Controller.php
+++ b/plugins/UserCountryMap/Controller.php
@@ -63,7 +63,7 @@ class Controller extends \Piwik\Plugin\Controller
         $view->defaultMetric = 'nb_visits';
 
         // some translations
-        $view->localeJSON = Common::json_encode(array(
+        $view->localeJSON = json_encode(array(
                                                      'nb_visits'            => Piwik::translate('General_NVisits'),
                                                      'one_visit'            => Piwik::translate('General_OneVisit'),
                                                      'no_visit'             => Piwik::translate('UserCountryMap_NoVisit'),
@@ -90,7 +90,7 @@ class Controller extends \Piwik\Plugin\Controller
         $view->metrics = $config['metrics'] = $this->getMetrics($idSite, $period, $date, $token_auth);
         $config['svgBasePath'] = 'plugins/UserCountryMap/svg/';
         $config['mapCssPath'] = 'plugins/UserCountryMap/stylesheets/map.css';
-        $view->config = Common::json_encode($config);
+        $view->config = json_encode($config);
         $view->noData = empty($config['visitsSummary']['nb_visits']);
 
         return $view->render();
@@ -198,7 +198,7 @@ class Controller extends \Piwik\Plugin\Controller
         }
 
         if ($encode) {
-            $params = Common::json_encode($params);
+            $params = json_encode($params);
         }
         return $params;
     }
diff --git a/plugins/Widgetize/Controller.php b/plugins/Widgetize/Controller.php
index 043ff8134d49844a6d0a60abe10d4d5a8998df67..5b1d31b5867b0a25b5f3e16ab2b58330b61241cb 100644
--- a/plugins/Widgetize/Controller.php
+++ b/plugins/Widgetize/Controller.php
@@ -22,7 +22,7 @@ class Controller extends \Piwik\Plugin\Controller
     public function index()
     {
         $view = new View('@Widgetize/index');
-        $view->availableWidgets = Common::json_encode(WidgetsList::get());
+        $view->availableWidgets = json_encode(WidgetsList::get());
         $this->setGeneralVariablesView($view);
         return $view->render();
     }
diff --git a/tests/PHPUnit/Fixtures/UITestFixture.php b/tests/PHPUnit/Fixtures/UITestFixture.php
index 8ff22824029203cf523fa92ccff7d13b9b6d7bb4..5eb6cf2610f45e89caa82e97f07b757b7b2f9184 100644
--- a/tests/PHPUnit/Fixtures/UITestFixture.php
+++ b/tests/PHPUnit/Fixtures/UITestFixture.php
@@ -249,7 +249,7 @@ class UITestFixture extends SqlDump
             } else {
                 $_GET['name'] = 'dashboard name' . $id;
             }
-            $_GET['layout'] = Common::json_encode($layout);
+            $_GET['layout'] = json_encode($layout);
             $_GET['idDashboard'] = $id + 1;
             FrontController::getInstance()->fetchDispatch('Dashboard', 'saveLayout');
         }
@@ -271,7 +271,7 @@ class UITestFixture extends SqlDump
         );
 
         $_GET['name'] = 'D4';
-        $_GET['layout'] = Common::json_encode($dashboard);
+        $_GET['layout'] = json_encode($dashboard);
         $_GET['idDashboard'] = 5;
         $_GET['idSite'] = 2;
         FrontController::getInstance()->fetchDispatch('Dashboard', 'saveLayout');
diff --git a/tests/PHPUnit/TestingEnvironment.php b/tests/PHPUnit/TestingEnvironment.php
index c52556fa7d2d28273b91d6c50296cf7600ca46e1..98e1566c5ddb0b142abc980562ce879c4c1506b2 100644
--- a/tests/PHPUnit/TestingEnvironment.php
+++ b/tests/PHPUnit/TestingEnvironment.php
@@ -249,7 +249,7 @@ class Piwik_TestingEnvironment
                 'contents' => $outputContent
             );
 
-            file_put_contents($outputFile, Common::json_encode($outputContents));
+            file_put_contents($outputFile, json_encode($outputContents));
         });
     }