臺灣博碩士論文加值系統

近年來，車用電子是半導體產業積極開發的重要市場，汽車的配備採用越來越多的電子產品。隨著電子技術進步，具備避免碰撞效果之主動式安全配備逐漸成為主流。本論文提出如何用雙鏡頭攝影機拍攝的影像，以數位影像處理的方式來避免碰撞。移動物體相較於靜止物體往往會是造成危險的潛在因子，車子的移動造成攝影機拍攝的畫面中的移動物體和靜止物體都具有行車紀錄器的相對移動(或稱自我移動)，所以我們的研究主要是如何從具有車子移動造成相對移動的影像分離出移動物體和靜止物體，進而判斷移動物體是否會造成危險。
演算法部分，我們利用雙鏡頭攝影機左右畫面所得到的視差加上左邊畫面的X坐標和Y坐標轉換成直角坐標的三維位置，加上前後畫面同一物體的位移，我們可以得到畫面中所有物體的位置與速度。由於畫面中物體的移動也包含自我移動，所以我們必需算出自我移動，算出自我移動後，將自我移動對移動物體和靜止物體所造成的移動移除即可分離出移動物體和靜止物體。因為前後時刻(1/30 sec)自我移動的變化很小，所以我們利用上一時刻的自我移動取代這一時刻的自我移動，並用它來分離出移動物體和靜止物體，然後再從靜止物體的移動反推出這一時刻的自我移動。找出移動物體後，我們再利用前後時刻(1/30 sec)移動物體移動的變化很小的特性對移動物體作移動預測，最後再判斷移動物體是否會對行車造成危險。
因軟體處理時間過長，故本論文針對具有平行化運算的區塊硬體化來加速運算速度。硬體方面，我們將需要用到座標平移與座標旋轉的運算用CORDIC電路來實現，並採用固定旋轉次數的CORDIC電路構架來降低進行座標平移運算與旋轉運算的CORDIC旋轉次數或是所需的硬體資源。
晶片實驗繥果採用TSMC/ARM 90 nm標準元件製程，工作頻率為346 MHZ，可處理HDTV1080P(1920 x 1080)的畫面。

In recent years, automotive electronics market is an important positive development of the semiconductor industry, there are more and more electronic products in a car. As electronic technology advances, active safety equipment with collisions avoidance is becoming main stream. In this thesis, we propose a technique how to avoid collisions in the image sequences captured by stereo camera. Moving objects are the most dangerous ones in many situations, and we implement a system that can detect independent moving objects through a stereo video platform.
Based on our proposed algorithm, we use the disparity information and the motion information (optical flow) through video preprocessing which video captured by a stereo camera to compute the 3D-position and 3D-motion of feature points of image. In order to detect the moving objects, it is necessary to compute the motion of moving observer (ego-motion). Since the variation of two ego-motions is small in 1/30 second, we use the former ego-motion to replace the current ego-motion. Then the moving objects and non-moving ones may be differentiated. After finding out the moving objects, we can estimate the position and motion next 1/30 second.
Due to long software processing time, the thesis attempts to speed up the processing by implementing hardware. We use the CORDIC architecture to implement the coordinate translation and coordinate rotation, and reduce the rotation steps and the hardware cost of CORDIC module by applying CORDIC architecture of fixed-angle rotations.
The spec of the proposed hardware architecture is the HDTV1080p applications at 346MHZ in TSMC 90 nm process.

第一章 引言 1
一、 車用電子系統 1
二、 車用防撞系統 4
三、 立體影像防撞系統 5
四、 論文組織 6
第二章 基於立體影像的移動物體偵測相關理論與文獻 7
一、 深度資訊的產生 8
二、 速度資訊的產生 9
三、 自我移動(Ego-motion)與移動物體偵測 10
四、 自我移動與移動物體偵測相關文獻介紹 11
(一) Visual Ego Motion Estimation in Urban Environments based on U-V Disparity[1] 11
(二) Fast detection of moving objects in complex scenarios[3] 12
第三章 應用於行車紀錄器之移動物體與危險偵測演算法以及模擬結果 13
一、 前言 13
二、 移動物體的偵測 15
(一) 座標轉換 15
(二) 移動點的擷取 20
(三) 計算自我移動 26
三、 移動物體的移動估測 36
(一) 移動補償 36
(二) 移動估測 38
四、 危險偵測與警告 40
五、 模擬結果 44
第四章 硬體架構設計與實作 51
一、 前言 51
二、 硬體規格 51
三、 硬體架構設計 52
四、 各單元之硬體架構設計 53
(一) 移動點的擷取 53
(三) 移動估測 54
(四) CORDIC Module 55
五、 實作結果 68
(一) 數位IC之設計流程 68
(二) 晶片規格 70
(三) SYNTHESIS 72
(四) LAYOUT 73
第五章 結論 75
參考文獻 76

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