Lane detection is a cardinal functionality in state-of-the-art Advanced Driver Assistant Systems (ADAS). However, it is still not straightforward to fulfill the real-time performance demand of processing High Definition (HD) images with high robustness and scalability. To address this problem, we propose an improved lane detection algorithm based on top-view image transformation and two-stage RANdom SAmple Consensus (RANSAC) model fitting. By virtue of off-line affine homography matrix adaption to bound an adaptive Region Of Interest (ROI) for subsequent on-line Warp Perspective Mapping (WPM) transformation, the algorithm can analyze arbitrary on-road videos and generate adaptive ROI without priori knowledge about camera parameter. To ensure the scalability, we present a comprehensive parallel design of the application in a heterogeneous system consisting of multi-core CPU, GPU and FPGA. We show in detail how the potentially parallel task loads are implemented and optimized so that they can be mapped to the most suitable processor so as to achieve optimal performance. Experimental results reveal that our improved algorithm can robustly process the video streams with a higher accuracy. Moreover, the heterogeneous executions are capable of processing HD 1920×1080 images with runtime performance of 81.6 fps and 47.9 fps, respectively, on an AMD FirePro W7100 GPU and a Terasic Arria 10 FPGA.