Well , it WILL be costly.
The cheapest way is to use a Windows (!) box with a so called USB "Capture card" .
Where I live , they are sold as "Rescue your old Video Casettes !" kits. (~ 40 $)
I suppose you are being served MUCH better by an advanced device (h.264 digitizer) - cost starting about 99 $.
Then there are the elgato devices ("netstream") , 150$- 200$ - I suppose there are also products of competitors.
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