Online experiment crashes on video load

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Online experiment crashes on video load

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AKrishna	AKrishna posted 3 Years Ago ANSWER Post Details Share Post
Group: Forum Members Posts: 123, Visits: 417	+x AKrishna - 9/8/2022 Hi all, an odd one today... An online experiment (registered under my username in the EU region, named AOPA) is crashing for no discernable reason with no error log. Specifically, after the first two files in the batch are run (informed consent and demographics), the main experiment starts. The first block (testing whether participants can see and hear video) runs without issue, including the test video. Then, the experiment asks several attitude items before showing another video. However, in most (but not all) cases, Inquisit quits to desktop when the video file should be played, with no error logged. I had thought that the problem occurs due to the dynamic selection of the video stimulus from the second block on (it's done via clearing the /items property of the video element, then appending an item pointing to the video file whose name is constructed from various conditions), but the code runs fine offline and my online debugging shows that the filename is being correctly constructed. The videos are all uploaded as well. Could there be some limitation with the video item filenames that only applies online? I'll continue testing myself, but I would appreciate any input, as I get the feeling that this might be something in the backend that I don't have access to. OK, it appears to be running now, although I can't easily iterate and check whether every condition works. However, some videos that apparently consistently crashed the program now run after I reduced the length of their filenames. Is there any reason why item names like "videoname.mp4" would not function on Inquisit Web if they are longer than about 28 characters? Could the web server be truncating filenames over 24 characters (not counting the .mp4 extension)? This would explain the error and put any fears that individual videos might not work to rest. This would also be consistent with Inquisit's behavior: the program also crashed without an error message when confronted with a filename that didn't exist, but had been assigned as a video item. So if my past version was trying to access the videos using the full file names, but the files on the server had truncated names, that would explain my observed issue. Would appreciate confirmation so I can be reasonably sure the experiment will run for all videos
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AKrishna	AKrishna posted 3 Years Ago HOT Topic Details Share Topic
Group: Forum Members Posts: 123, Visits: 417	Hi all, an odd one today... An online experiment (registered under my username in the EU region, named AOPA) is crashing for no discernable reason with no error log. Specifically, after the first two files in the batch are run (informed consent and demographics), the main experiment starts. The first block (testing whether participants can see and hear video) runs without issue, including the test video. Then, the experiment asks several attitude items before showing another video. However, in most (but not all) cases, Inquisit quits to desktop when the video file should be played, with no error logged. I had thought that the problem occurs due to the dynamic selection of the video stimulus from the second block on (it's done via clearing the /items property of the video element, then appending an item pointing to the video file whose name is constructed from various conditions), but the code runs fine offline and my online debugging shows that the filename is being correctly constructed. The videos are all uploaded as well. Could there be some limitation with the video item filenames that only applies online? I'll continue testing myself, but I would appreciate any input, as I get the feeling that this might be something in the backend that I don't have access to.
	Reply Like 6