Algorithm 1. Pseudocode of D-ROI and DFS methods for minimizing computing load.

frame ← the frames from camera device s ← vehicular speed value ΔA ← vehicular acceleration value Initialised ROI = S-ROI, frame_count = 0, D-ROI_count = 0, target_searching = false for all frame do     frame _count = (frame _count + 1) % FRinp     FRskip% = min [α × standardisation(s) × standardisation (ΔA), FRinp]     if FRskip % frame_count = 0 then         if ROI ≠ S-ROI then            D-ROI_ count += 1         end if     else then         target_searching, CR = recognition_algorithm (ROI)         If target_searching = false or D-ROI_ count > D-ROI_ threshold then            ROI = S-ROI            D-ROI_ count = 0         else then            D-ROI = CR + MR            ROI = D-ROI            D-ROI_ count += 1         end if     end if end for