About this app
General information:"Where Is Explosion?" - is an application designed to determine the distance to an explosion based on video, whether it is a lightning strike, a firework explosion or any other explosion. The main requirements: the presence of a flash and the sound of an explosion on the video.
The app calculates the difference between the time when the sound of the explosion starts and the time when the flash occurs, and then multiplies that value by the speed of sound.
How and which video to choose:
First, go to the video processing menu. Next, click on the black rectangle that says "Click to choose a video." A file selection window will appear, select a video and click OK. After that, the video will be processed, wait for the end of processing.
Processing will take longer for longer videos, so we recommend trimming the video (using another program) to process only the moments you need. Be sure to make sure that the flash and the sound of the explosion are visible on the video.
If there are other flashes in the video, it is recommended to zoom the video (using another program) so that only the flash you are interested in is visible.
To select a new video, click the video selection button again.
Work with graphs:
After the video processing is completed, the program will build 2 graphs: red - light graph, blue - sound graph.
The program will automatically place sliders where sudden changes in values have occurred. However, to obtain more accurate calculations, it is recommended to set the sliders manually. To do this, just hold your finger on one of the sliders and drag it.
By moving the left slider, you can rewind the video. Drag it to the moment the flash starts.
The right slider should be set at the moment the explosion sound starts. To make sure you have set the slider correctly, press the play/pause button and watch the video before it ends. The left slider indicates the beginning, and the right - the end of the selected moment.
The position of the sliders can be changed at any time.
Below the graphs and the "start/pause" button, there will be a text with the results of the approximate calculation of the distance to the explosion.
Additional values:
To obtain a more detailed calculation of the distance to the explosion, you can also specify additional values:
1. Number of frames per second (FPS). Affects the error of the distance to the explosion.
2. Air temperature. Affects the formula for calculating the speed of sound.
To specify these values, click on "More ▼" under the text with the calculation results.
Results:
To summarize, with the application "Where Is Explosion?" you will be able to:
1. Calculate the distance to the explosion.
2. Calculate the distance to lightning.
3. Calculate the distance to the fireworks.