This already exists on some charting packages, would be like a market profile for each candle. Similar idea was, Morge or someone in his group awhile back was working on a charting package that tied volume into the candle's color (basically on the CME markets where true volume can be measured). It was similar to a market facilitation index, doji and reversing candles were color coded if volume exceeded or shrank from a defined norm, (something along those lines) helped spot false separations.