Bureaucrats, dave_user, Administrators
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*t<sub>A</sub> = 50.000+3.000 = 53.000s
Once the recording is saved on the SSD, the verification consists of checking the first frame, the last frame, and the x_alarm frame (<code>n_+0.000000000.bmp</code>). They should show respectively:Ideally*The timer displaying 42.000*The timer displaying 53.000*The timer displaying 50.000. Let's analyze one of the recording buffers that were captured this way. It refers to the alarm recorded on Agust 8, 2020 at 12.09.51 CEST. The following images show the frame associated with t<sub>B'</sub>, t<sub>A'</sub>, and t<sub>0'</sub> respectively. [[File:000000 -8.133780480.png|thumb|center|600px|Fig. 5: Frame associated with t<sub>B'</sub>] [[File:003332 +3.046812160.png|thumb|center|600px|Fig. 6: Frame associated with t<sub>A'</sub>] [[File:002424 +0.000000000.png|thumb|center|600px|Fig. 7: Frame associated with t<sub>0'</sub>] First of all, we notice that the timer's last digit always appears as "8". This is due to the fact that 7-segment displays are refreshed every millisecond, but the acquisition rate by the image sensor is slower. Therefore, the last digit is not meaningful and can be ignored. By the way, the major factor that determines the acquisition rate is the [https://en.wikipedia.org/wiki/Shutter_speed exposure time], which was set to 3300us in this case. That said, frames t<sub>B'</sub> and t<sub>A'</sub> are pretty close to what we expected:*t<sub>B'</sub> frame**This frame is named <code>000000_-8.133780480.png</code>**The timer displays 41.86x*t<sub>A'</sub> frame**This frame is named <code>003332_+3.046812160.png</code>**The timer displays 53.04xWhat about t<sub>0'</sub> frame? It is named correctly (<code>002424_+0.000000000.png</code>), but the timer does not display (98.88x) what we expected at all. Why? To find the answer, let's have a look at the subsequent frame: [[File:002425 +0.003355520.png|thumb|center|600px|Fig. 8: Frame following the alarm frame] Timer displays 50.00x. This means that, in the middle of the exposure window associated with the alarm frame, the timer refreshed all the 7-segment displays from something like 49.xyz to 50.abc, so all the digits were affected. In conclusion, the assessment of these frames was completed successfully because the discrepancies are in the order of hundreds of milliseconds,therefore much slower than the size of the recording window.
==Future work==
