diff --git a/controllers/serveController.js b/controllers/serveController.js
index 18ec4526..fdbfcd81 100644
--- a/controllers/serveController.js
+++ b/controllers/serveController.js
@@ -5,13 +5,6 @@ const DEFAULT_THUMBNAIL = 'https://spee.ch/assets/img/video_thumb_default.png';
 const NO_CHANNEL = 'NO_CHANNEL';
 const NO_FILE = 'NO_FILE';
 
-function chooseThumbnail (claimInfo, defaultThumbnail) {
-  if (!claimInfo.thumbnail || claimInfo.thumbnail.trim() === '') {
-    return defaultThumbnail;
-  }
-  return claimInfo.thumbnail;
-}
-
 module.exports = {
   getClaimId (channelName, channelId, name, claimId) {
     if (channelName) {
@@ -82,7 +75,7 @@ module.exports = {
               element['directUrlLong'] = `/${channelName}:${longChannelId}/${element.name}.${fileExtenstion}`;
               element['showUrlShort'] = `/${channelName}:${shortChannelId}/${element.name}`;
               element['directUrlShort'] = `/${channelName}:${shortChannelId}/${element.name}.${fileExtenstion}`;
-              element['thumbnail'] = chooseThumbnail(element, DEFAULT_THUMBNAIL);
+              element['thumbnail'] = module.exports.chooseThumbnail(element, DEFAULT_THUMBNAIL);
             });
           }
           resolve({
@@ -112,8 +105,32 @@ module.exports = {
           if (!claim) {
             throw new Error('no record found in Claim table');
           }
-          claim.dataValues.thumbnail = chooseThumbnail(claim.dataValues.thumbnail, DEFAULT_THUMBNAIL);
+          claim.dataValues.thumbnail = module.exports.chooseThumbnail(claim.dataValues.thumbnail, DEFAULT_THUMBNAIL);
+          claim.dataValues.fileExt = module.exports.determineFileExtensionFromContentType(claim.dataValues.contentType);
           return claim.dataValues;
         });
   },
+  determineFileExtensionFromContentType (contentType) {
+    switch (contentType) {
+      case 'image/jpeg':
+        return 'jpeg';
+      case 'image/jpg':
+        return 'jpg';
+      case 'image/png':
+        return 'png';
+      case 'image/gif':
+        return 'gif';
+      case 'video/mp4':
+        return 'mp4';
+      default:
+        logger.info('showing unknown file type as image/jpeg');
+        return 'jpeg';
+    }
+  },
+  chooseThumbnail (claimInfo, defaultThumbnail) {
+    if (!claimInfo.thumbnail || claimInfo.thumbnail.trim() === '') {
+      return defaultThumbnail;
+    }
+    return claimInfo.thumbnail;
+  },
 };
diff --git a/routes/serve-routes.js b/routes/serve-routes.js
index 41cea422..6f8cebcf 100644
--- a/routes/serve-routes.js
+++ b/routes/serve-routes.js
@@ -177,43 +177,43 @@ function determineName (uri) {
 function showAssetToClient (claimId, name, res) {
     // check for local file info, resolve the claim, and get the short
   return Promise
-    .all([getClaimRecord(claimId, name), db.Claim.getShortClaimIdFromLongClaimId(claimId, name)])
-    .then(([claimInfo, shortClaimId]) => {
-      logger.debug('claimInfo:', claimInfo);
-      logger.debug('shortClaimId:', shortClaimId);
-      return serveHelpers.showFile(claimInfo, shortClaimId, res);
-    })
-    .catch(error => {
-      throw error;
-    });
+      .all([getClaimRecord(claimId, name), db.Claim.getShortClaimIdFromLongClaimId(claimId, name)])
+      .then(([claimInfo, shortClaimId]) => {
+        logger.debug('claimInfo:', claimInfo);
+        logger.debug('shortClaimId:', shortClaimId);
+        return serveHelpers.showFile(claimInfo, shortClaimId, res);
+      })
+      .catch(error => {
+        throw error;
+      });
 }
 
 function showPlainAssetToClient (claimId, name, res) {
   return Promise
-        .all([getClaimRecord(claimId, name), db.Claim.getShortClaimIdFromLongClaimId(claimId, name)])
-        .then(([claimInfo, shortClaimId]) => {
-          logger.debug('claimInfo:', claimInfo);
-          logger.debug('shortClaimId:', shortClaimId);
-          return serveHelpers.showFileLite(claimInfo, shortClaimId, res);
-        })
-        .catch(error => {
-          throw error;
-        });
+      .all([getClaimRecord(claimId, name), db.Claim.getShortClaimIdFromLongClaimId(claimId, name)])
+      .then(([claimInfo, shortClaimId]) => {
+        logger.debug('claimInfo:', claimInfo);
+        logger.debug('shortClaimId:', shortClaimId);
+        return serveHelpers.showFileLite(claimInfo, shortClaimId, res);
+      })
+      .catch(error => {
+        throw error;
+      });
 }
 
 function serveAssetToClient (claimId, name, res) {
   return getLocalFileRecord(claimId, name)
-        .then(fileInfo => {
-          logger.debug('fileInfo:', fileInfo);
-          if (fileInfo) {
-            return serveHelpers.serveFile(fileInfo, res);
-          } else {
-            return res.status(307).json({status: 'success', message: 'resource temporarily unavailable'});
-          }
-        })
-        .catch(error => {
-          throw error;
-        });
+      .then(fileInfo => {
+        logger.debug('fileInfo:', fileInfo);
+        if (fileInfo) {
+          return serveHelpers.serveFile(fileInfo, res);
+        } else {
+          return res.status(307).json({status: 'success', message: 'resource temporarily unavailable'});
+        }
+      })
+      .catch(error => {
+        throw error;
+      });
 }
 
 module.exports = (app) => {
@@ -259,11 +259,11 @@ module.exports = (app) => {
       }
       // show, showlite, or serve
       switch (responseType) {
-        case SERVE:
+        case SHOW:
           return showAssetToClient(claimId, name, res);
         case SHOWLITE:
           return showPlainAssetToClient(claimId, name, res);
-        case SHOW:
+        case SERVE:
           return serveAssetToClient(claimId, name, res);
         default:
           break;
@@ -303,11 +303,11 @@ module.exports = (app) => {
           }
           // show, showlite, or serve
           switch (responseType) {
-            case SERVE:
+            case SHOW:
               return showAssetToClient(claimId, name, res);
             case SHOWLITE:
               return showPlainAssetToClient(claimId, name, res);
-            case SHOW:
+            case SERVE:
               return serveAssetToClient(claimId, name, res);
             default:
               break;