Merge remote-tracking branch 'origin/pr/1152'

airsonic-main/src/main/java/org/airsonic/player/controller/CoverArtController.java

@@ -628,10 +628,10 @@ public class CoverArtController implements LastModified {
             try {
                 in = getImageInputStreamForVideo(mediaFile, width, height, offset);
                 BufferedImage result = ImageIO.read(in);
-                if (result == null) {
-                    throw new NullPointerException();
-                }
+                if (result != null) {
                     return result;
+                }
+                LOG.warn("Failed to process cover art for " + mediaFile + ": {}", result);
             } catch (Throwable x) {
                 LOG.warn("Failed to process cover art for " + mediaFile + ": " + x, x);
             } finally {