HartSift: A High-Accuracy and Real-Time SIFT based on GPU

Scale Invariant Feature Transform (SIFT) is one of the most popular and robust feature extraction algorithms for its invariance to scale, rotation and illumination. It has been widely adopted in many fields, such as video tracking, image stitching, simultaneous localization and mapping (SLAM), structure from motion (SFM) and so on. However, high computational complexity constrains its further application in real-time systems. These systems have to make a tradeoff between accuracy and performance to achieve real-time feature extraction. They adopt other faster algorithms but with less accuracy, like SURF and PCA-SIFT. In order to address this problem, this paper proposes a GPU-accelerated SIFT using CUDA, named HartSift, which realizes high-accuracy and real-time feature extraction by making full use of computing resources of CPU and GPU within a single machine. Experiments show that, on the NVIDIA GTX TITAN Black GPU, HartSift can process an image within 3.14 similar to 10.57ms (94.61 similar to 318.47fps) according to the size of images. In addition, HartSift is 59.34 similar to 75.96 times and 4.01 similar to 6.49 times faster than OpenCV-SIFT (a CPU version) and SiftGPU (a GPU version), respectively. In the meantime, HartSift's performance and CudaSIFT's (the fastest GPU version so far) are almost the same, while HartSift's accuracy is much higher than CudaSIFT's.