靜態與動態立體影像之影像品質評估

Evaluation on 3D Static Image and Dynamic Film Image Quality

張詠昇(Yung-Sheng Chang)

指導教授 ： 黃雪玲

國立清華大學/工學院/工業工程與工程管理學系/碩士(2013年)

https://doi.org/10.6843/NTHU.2013.00185

摘要

影像品質一向為3D立體顯示器產業內一重要之討論議題。好的影像品質容易帶給觀眾觀看立體影片時有更好的娛樂經驗並且在軍事或醫療用途上使用立體影像時會有更好的表現績效。因此本研究主要在探討不同因子如何影響靜態與動態立體影像的影像品質。
本研究共分為兩階段，第一階段為使用田口方法探討顯示器亮度、環境照度、視差範圍、影像亮度對比範圍和觀看時間對於靜態影像品質與深度知覺測量之影響。第二階段實驗則探討不同主體、移動速度和起始視差位置度對於停止視差位置之判斷與主觀影像品質評估之影響。
本研究結果顯示對於靜態影像而言，不同依變項會有不同的最佳因子組合，好比為了要有最佳的整體影像品質環境照度應設為103 lux而為了要有最佳的深度知覺視差範圍和觀看時間應設為0.85o和90分鐘。至於動態影像之研究結果顯示，當主體的結構較為簡單且主體是從顯示器後方較遠的位置開始往前運動時，會有較佳的主觀影像品質評估。停止視差位置判斷的分析結果則可做為主體在不同移動速度與視差位置下運動時的一停止位置指標，以避免影像品質開始變差而影響到觀看經驗。總而言之，視差為影響深度知覺的重要因子。當靜態影像位於顯示器後方且觀看時間越長時，或者動態影像從顯示器後方開始往前運動時，深度知覺的判斷會最深。

關鍵字

影像品質 ； 視差 ； 環境照度 ； 移動速度

並列摘要

Image quality has consistently been an important issue in the 3D display industries, given the fact that better image quality could improve entertainment experience for viewers while watching dynamic films or improve operating efficiency in military or medial use while watching static 3D images. Therefore, this study aimed to investigate the effect of different factors on static and dynamic film image quality.
This study consisted of two stages. In the first stage, a Taguchi method was used to investigate display luminance, ambient illumination, range of disparity, brightness contrast ratio, and viewing time effect on static image quality and depth perception measurement. In the second stage of experiment, we examined the effect of different objects, moving velocities and disparity locations on dynamic film’s judgment of ended disparity and subjective image quality evaluation.
The result for static image showed that the optimal combination depended on the type of dependent variable. For instance, in order to have the best image quality, the ambient illumination needed to be at 103 lux. However, to obtain the best depth perception, the range of disparity and the viewing time needed to be at 0.85o and 90 minutes respectively. For dynamic film, the structure of the object should be simpler and the starting disparity location should be located behind the display to obtain the best subjective image quality. The judgment of ended disparity could be a stopping point for the film to prevent the film’s image quality to degrade under different moving velocities and disparity locations. In conclusion, disparity is a vital factor that affects the perception of depth. When the static image is located behind the display with longer viewing time and the dynamic films starting location is behind the display, the depth perception would be judged as deeper.

並列關鍵字

Image quality ； disparity ； ambient illumination ； moving velocity

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