應用於色彩座標調整系統之CORDIC架構設計與FPGA硬體實現

Color coordinate adjustment system based on CORDIC architecture design and FPGA hardware implementation

鄭智文(Chih-Wen Cheng)

指導教授 ： 范育成

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2010年)

摘要

目前市面上的顯示設備已經發展成多元化，常見的如一般映像管電視機、液晶螢幕、液晶電視、電漿電視、背投影電視、投影機等等，不同成像原理設備以及電視系統標準之間的色彩表現經常會有些差異存在，例如：跨媒體之間的色域範圍是不同的、電視播放系統的色彩角度誤差以及數位化解析度的誤差，因此彩色調整技術對影像系統產品品質有決定性的影響，消費者則會受到主觀的彩色影像品質及影像處理功能所影響。
大部分的顯示設備，為了強調產品在色調上擁有極佳的色彩表現，會刻意地加入專屬的色彩調整模式，然而，這些誇張影像對比與色彩飽和的調整模式，卻使得螢幕上所呈現的影像色彩與實際影像產生了相當程度的差異，傳統色彩調整所提供的方式往往是全面性的變動，即使希望調整的色彩範圍是局部的，但實際上所呈現的畫面卻是整張圖的所有色彩一起變動。本文所提供的方式，利用電視系統的色彩座標軸將影像分成六個色軸角度，並且增加一軸可以任選座標軸角度，藉以強化所需調整之角度，在此我們稱之為色彩座標調整系統(Color Coordinate Adjustment System)，該方法以數位座標旋轉計算器(Coordinate Rotation Digital Computer)為架構，提供調整色軸的角度旋轉，可以有效以硬體來實現，達到即時(real-time)運算調整，而且具有良好的色彩調整效果。

關鍵字

色彩座標調整系統 ； 數位座標旋轉計算器

並列摘要

Currently consumer market has developed diversified display devices, such as CRT TV, LCD monitors, LCD TV, plasma TV, rear projection TV, projectors, etc.. The color performance between different principles of imaging devices and television system standards often exist some differences, such as the color gamut among cross-media is different, the color angle error of television system and the error of digital resolution. Therefore, adjustable color image system and technology have a decisive impact of product quality. Consumers will be affected by the subjective color image quality and image-processing functions.
In order to emphasize excellent performance of color tone for product, most display devices would be deliberately added exclusive color adjustment modes. However, these adjustment modes which exaggerate image contrast and color saturation make the color images and actual images presenting on the screen and producing a considerable difference of degree. Traditional color adjustment methods often adopt fully-style color adjustment. Even if we want to adjust the color range locally, the color change of picture is still altered entirely. The proposed methods in this thesis using color coordinate of television system to divide the image into six color-axes and increase one axis to strengthen color presentation. We name this method Color Coordinate Adjustment System (CCAS). This method adopts coordinate rotation digital computer architecture to calculate the rotation for adjusting color axis angle. The scheme is implemented using FPGA platform, achieves real-time computing adjustment and provides well color adjustment results.

並列關鍵字

Color Coordinate Adjustment System ； Coordinate Rotation Digital Computer

參考文獻

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