OCR software to extract info from onboard telemetry overlays

[hollus]

Hi all,

Does anyone know of any free OCR software that can be used to extract text from an specific position in a video, possibly for each frame? Ideally it should be capable of using online videos. Maybe an OCR software that continuously scans a portion of the screen, then the relevant information can be placed in that desktop position by moving the window...
In particular I am thinking of extracting the speed data from onboard videos, so a software capable of extracting only numbers would be perfectly OK.

Thanks in advance.

[Kynei]

Hi all,

Does anyone know of any free OCR software that can be used to extract text from an specific position in a video, possibly for each frame? Ideally it should be capable of using online videos. Maybe an OCR software that continuously scans a portion of the screen, then the relevant information can be placed in that desktop position by moving the window...
In particular I am thinking of extracting the speed data from onboard videos, so a software capable of extracting only numbers would be perfectly OK.

Thanks in advance.

Hi hollus

Probably you saw this telemetry image with a Q1 lap comparisson between Hamilton and Alonso in forocoches' F1 thread. The data is extracted from the official live timing app.



I used a free Tesseract OCR engine based software called VietOCR, which lets you to recognise text from multiple images at once and save it directly as txt files. To facilitate the recognition process I cutted the portion which contains the speed data and inverted the colours with the video editor VirtualDub.



After merging every txt file generated by the OCR software into a single one you can plot it easily taking care of any data errors first.

Greetings

[hollus]

Thank you very much! That looks doable. A bit of preparation and postprocessing work, but quite doable!
And btw, I used your graph in the McLaren team thread, thanks for that too.

[Kynei]

Ok, no problem! It seems the easiest way as far as we can't access to the data inside the *.dat files from live timing sessions

[silente]

Is the x axis showing the real lap time or only the measured sample corresponding to each speed value reported in the graph?

[hollus]

I think the x axis is "video time" which would equate lap time.
I just noticed something interesting in that graph (Hamilton was on the harder compound, Alonso on the softer). By 26 seconds Alonso is significantly behind, but 55 seconds he has caught up, being faster than Hamilton through that section (then he loses a ton of time on the long straight). But his apex speeds are no better than Hamiltons! Either this McLaren is a braking monster, which does not seem to be the case in that lap, or Alonso is spending "less time in the corners", to the tune of 1 tenth per corner, again without lower apex speeds. Interesting...

[silente]

interesting tool in any case.

Could be interesting to have access also to other data, like g accelerations for example, to then plot them also in a graph against time.

From the speed trace also a distance x axis could be easily calculated.

Any download link to the software to be used?