Dewesoft X supports many different video cameras online. But there are cases (for example with very fast video cameras) where we have data file and the video file coming from the frame grabber. It is possible to synchronize those two files in Analysis mode with two simple steps:
- Include Video file to copy video file and re-name it according File name conventions
- Video synchronization to synchronize video file with analog data in the Dewesoft Xdata file with:
- synchronization settings
- resynchronize files
- storing post synchronization information
AVI and DVI format is required for synchronization!
File name conventions
To include the high-speed video in Dewesoft X, there are only a few steps necessary:
- After the acquisition of video file and the Dewesoft X measurement data, please copy *.avi high-speed camera file to the directory (via Windows Explorer) where the Dewesoft X data to be synchronized is located.
- Please rename the video file to this specification: xxxxx.cam0.avi, where 'xxxxx' is the name of the Dewesoft Xfile to be synchronized. If we have more video files, we can name then xxxx.cam0.avi, xxxx.cam1.avi, xxxx.cam2.avi, and so on.
Image 31: Rename the video files to the xxx.cam0.avi format
- Image 31 shows an example of how this looks like. Original Dewesoft X file is DF_AUTO_VTE_brake_test_thermo.dxd and therefore a video clip should be named DF_AUTO_VTE_brake_test_thermo.cam0.avi. After this open Dewesoft X, press the Analysis button to enter the Analyse mode and you should see already video file as part of the Dewesoft X data file.
After including video in the data file double click the file to open it. Dewesoft X will recognize that this file has no synchronization information included and will ask to synchronize it manually.
Image 32: Video post synchronization
The window displays the video file name and the number of stored frames (Frames found). Change the frame rate to the real capture rate of the camera (sometimes the .avi files hold correct values, but most of the time not). As an additional help, the Video size field shows you the video duration (length in seconds) at the currently selected frame rate.
After that, specify the Pre trigger - how many pictures have been taken before the video trigger occurred (choose between frames, seconds, and milliseconds).
Trigger time finally defines the start position of the video: from trigger means the first appearance of a trigger event (or start of measurement - storing of analog data). In this case, both the measurement systems and video cameras require the same trigger source.
The second way is to define video start from relative time. In this case, the mentioned time counts from the beginning of measurement in seconds.
After you have done all settings press OK button - the files will now be synchronized, but the synchronization information is not stored at this time! Dewesoft X will now display both files in the Video display.
The video display can be handled as any other instrument within Dewesoft X: zoom, scroll and scale, play, ... - whatever is required. If the synchronization is not perfect, it can still be adjusted by selecting the tab Data files -> Post-sync. video.
Image 33: Post-sync video icon
NOTE: This option is only available if the synchronization information hasn't been stored.
Now you get the same Video post synchronization window as described in Synchronization settings. With an additional feature: Trigger time.
Image 34: Post-sync from trigger
This is really a great feature, because you can zoom into your display, move the yellow cursor in the recorder to exactly defined position, and select Video post synchronization from the Data menu. If you do so, the video will be placed in the position of the yellow cursor. This will also work if a pretrigger is required.
Using this function, you can move position of the video file within the data file forward and backward as required.
Storing post synchronization information
Currently, there is no separate storage button available. To avoid doing all the synchronization setup every time, simply click on the Analysis button to go back to the file selection list. A warning message will now appear asking if the synchronization information should be stored now or not.
If you select Yes, the information is stored directly into the video file (not the data file) and is now available at any time, no further synchronization is required.
Warning: If you have stored post synchronization information once, it can't be changed anymore.
Therefore you should always keep a copy of the original video file, which doesn't contain this synchronization information.
Remove video from data files
To remove the assigned video from the data file, simply rename (or delete) the video file. In this case, the video file is not visible anymore in Dewesoft X. As the synchronization information is stored in the video file, there isn't even an error message, because the data file doesn't miss the video.
Make a short test: Rename the video back to the data file name and open it in Dewesoft X - the video is back and still synchronized.