I receive lots of errors like this everyday on my logs:
2017-08-14 22:12:17 (...) ErrorException from line 104 of .../mediawiki-1.29.0/includes/media/GIF.php: PHP Notice: Undefined index: frameCount #0 .../mediawiki-1.29.0/includes/media/GIF.php(104): MWExceptionHandler::handleError(integer, string, string, integer, array) #1 .../mediawiki-1.29.0/includes/media/Bitmap.php(180): GIFHandler->isAnimatedImage(LocalWikiDexFile) #2 .../mediawiki-1.29.0/includes/media/TransformationalImageHandler.php(246): BitmapHandler->transformImageMagick(LocalWikiDexFile, array) #3 .../mediawiki-1.29.0/includes/filerepo/file/File.php(1141): TransformationalImageHandler->doTransform(LocalWikiDexFile, string, string, array) #4 .../mediawiki-1.29.0/includes/filerepo/file/File.php(1104): File->generateAndSaveThumb(TempFSFile, array, integer) #5 .../mediawiki-1.29.0/thumb.php(432): File->transform(array, integer) #6 .../mediawiki-1.29.0/includes/poolcounter/PoolCounterWorkViaCallback.php(69): {closure}() #7 .../mediawiki-1.29.0/includes/poolcounter/PoolCounterWork.php(123): PoolCounterWorkViaCallback->doWork()
2017-08-14 22:50:48 (...) ErrorException from line 93 of .../mediawiki-1.29.0/includes/media/PNG.php: PHP Notice: Undefined index: frameCount #0 .../mediawiki-1.29.0/includes/media/PNG.php(93): MWExceptionHandler::handleError(integer, string, string, integer, array) #1 .../mediawiki-1.29.0/includes/filerepo/file/File.php(619): PNGHandler->isAnimatedImage(LocalWikiDexFile) #2 .../mediawiki-1.29.0/includes/page/ImagePage.php(566): File->canAnimateThumbIfAppropriate() #3 .../mediawiki-1.29.0/includes/page/ImagePage.php(150): ImagePage->openShowImage() #4 .../mediawiki-1.29.0/includes/actions/ViewAction.php(68): ImagePage->view() #5 .../mediawiki-1.29.0/includes/MediaWiki.php(499): ViewAction->show() #6 .../mediawiki-1.29.0/includes/MediaWiki.php(293): MediaWiki->performAction(ImagePage, Title) #7 .../mediawiki-1.29.0/includes/MediaWiki.php(862): MediaWiki->performRequest() #8 .../mediawiki-1.29.0/includes/MediaWiki.php(523): MediaWiki->main() #9 .../mediawiki-1.29.0/index.php(43): MediaWiki->run() #10 {main}
The wiki was migrated from an old MediaWiki 1.19. Maybe the image metadata needs to be refreshed, but there should be a sanity check that metadata contains the frameCount property.