本文讨论了建立四反射镜环形反馈系统的有关问题，探讨了利用环形反馈系统控制图象对比度变化的原理。
This paper studies the establishment of four-mirror circle feedback system and the principle of controlling contrast changes of the image pattern by this system.
由于在线掌纹图象的对比度较低，掌纹中的细小皱纹和乳突纹会形成一定的噪声，掌纹中的线特征的模式十分复杂，因此对掌纹进行线特征提取是一项具有挑战性的研究课题。
Line patterns in palmprint are very complicated because of the low contrast and the heavy noise caused by fine wrinkles and ridges, so it is a challenging task to complete the feature extraction.
实验表明，这种新方法能极大程度地消除金属伪影，并能显著提高图象的对比度。
Experiments show that by our method, the streaks caused by the metallic implants can be greatly suppressed and the contrast can be significantly improved.
应用推荐