運用同步式多重亮度紅外線打光器之夜間監控系統

Abstract

本研究針對夜間監控進行改善，改善的內容為提升影像品質。之前[1]所研究之方法，提出夜間監控系統上使用多重紅外線打光可動態調整影像的清晰度，使不同距離的目標物或人得到足夠的光源，所以影像的細節可以保留。由於紅外線系統和夜間監控系統的控制是獨立的，針對不同距離的前景，電荷耦合感測元件會產生不同亮度組合的影像，而需對影像亮度使用分群(clustering)的方法進行分類；而互補式金屬氧化物半導體感測元件則會於同一張畫面的局部亮度將不一致的情形，此情形將會降低亮度分群的準確度也同時也將增加影像處理的複雜度。本研究利用多重亮度紅外線打光器(multi-intensity infrared illuminator)與數位紅外線攝影系統的曝光(exposure)之週期同步的方法結合成一新式的夜間監控系統(nighttime surveillance system)，可改善之前[1]研究所發生同一張畫面的局部亮度不一致的問題。

This study involves a new technique which improves the image quality of nighttime surveillance. According to the previous design [1], with a multi-intensity infrared illuminator, high dynamic range images can be captured by the nighttime surveillance system. The illuminator offers variable infrared intensity to illuminate the objects or humans at different distances. Therefore, the details of the images can be retained. Since the controllers of multi-intensity infrared illuminator system and nighttime surveillance system are independent, image foregrounds at different distances must be obtained from an additional luminance clustering technique for CCD cameras. For the CMOS cameras, the local luminance of one single frame may not correspond to the same luminance level, which will reduces the accuracy of luminance clustering and increases the complexity of analysis. This study presents a new system design that uses the only one system controller to synchronize the illuminator and the exposure timing. This structure will save the hardware cost and solve the inconsistent luminance problem of the previous design [1].