Tonet Oliver, Thoranaghatte Ramesh U, Megali Giuseppe, Dario Paolo
CRIM Lab, Scuola Superiore Sant'Anna, Pisa, Italy.
Comput Aided Surg. 2007 Jan;12(1):35-42. doi: 10.3109/10929080701210782.
We present an approach to localizing endoscopic instruments with respect to the camera position, based purely on processing of the endoscope image. No localizers are needed; the only requirement is a colored strip at the distal part of the instrument shaft to facilitate image segmentation. The method exploits perspective image analysis applied to the cylindrical shape of the instrument shaft, allowing measurement of the instrument position and orientation with five degrees of freedom. We describe the method theoretically, and experimentally derive calibration curves for tuning the parameters of the algorithm. Results show that the method can be used for applications where accuracy is not critical, such as workspace measurement, gesture analysis, augmented-reality guidance, telementoring, etc. If this method is used in combination with an endoscope tracker or a robotic camera holder, full localization with respect to the patient reference frame can be achieved.
我们提出了一种仅基于内窥镜图像的处理来确定内窥镜器械相对于摄像头位置的方法。无需定位器；唯一的要求是在器械轴的远端有一条彩色条带以方便图像分割。该方法利用应用于器械轴圆柱形的透视图像分析，能够以五个自由度测量器械的位置和方向。我们从理论上描述了该方法，并通过实验得出校准曲线以调整算法参数。结果表明，该方法可用于精度要求不高的应用，如工作空间测量、手势分析、增强现实引导、远程指导等。如果将此方法与内窥镜跟踪器或机器人摄像头支架结合使用，就可以实现相对于患者参考框架的完全定位。
