+ + We listed and answered frequently asked questions below. + Please also let us know which aspects are working well and which could be improved via the Feedback Form. + We really appreciate your input! +
++ + Q1: Why sometimes a dialog box popped up and asked me to enable video autoplay? + +
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+ A1: During labeling, videos need to play and loop automatically. + However, if a mobile device has data saver enabled, videos will stop autoplay. + Also, some mobile devices pause videos after users wake it up from sleeping mode. + In order to enable autoplay, browsers require user interactions, which is why the system shows the dialog box. +
++ + Q2: Why my labels did not pass the quality check? How did you define the quality? + +
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+ A2: For each batch (16 videos) on the page, the system randomly placed several videos with known answers, also called gold standards. + A batch will pass the quality check if you label these gold standards correctly. +
++ + Q3: Why sometimes I saw similar videos? Were they the same? + +
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+ A3: There can be two reasons. + Firstly, videos that have closer times (e.g., 8 and 8:10 am) can look similar due to the same weather and lighting conditions. + Secondly, gold standard videos for the quality check can appear again if you label many batches. +
++ + Q4: What are you planning to do with all these labeled data? + +
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+ A4: We will use these labeled videos to train a deep neural network for detecting smoke emissions. + While deep neural networks have been proven to outperform traditional models in various applications, training such large networks requires a considerable amount of labeled data, which is why we need volunteers' help. +
++ + Q5: Where do these video clips come from? + +
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+ A5: We selected and cropped several windows into videos from our camera network (as shown in the following image). + Most videos are from the the Clairton Coke Works camera, and some videos are from the Edgar Thomson Steel Works camera. + Each video contains 36 frames, which represent about 6 minutes in real-world time. +
+ ++ + Q6: Can I build a similar system with your code? + +
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+ A6: This project is open-sourced on GitHub. Please feel free to reuse the code. +
++ + Q7: Are there other actions that I can take to advocate for better air quality? + +
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+ A7: If you are interested in smoke reading (visual emissions observation using EPA Method 9), we recommend checking the smoke school training materials. +
++ + Q8: Why does this tool not support systems that are older than Android 7 and iOS 11? + +
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+ A8: When labeling smoke, this tool shows 16 videos at the same time. + Older devices have difficulties in playing these videos, which results in poor user experiences. +
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