Re: [問題] AWB和自訂白平衡的差別?

作者: ad47 (我現身了~)   2014-10-23 22:51:58
先隨便節錄三篇關於白平衡書籍、論文中關於白平衡作用的敘述
Mathematically, we would thus expect the color stimulus of the same object to
be different under different lighting conditions. However,our experience
seems to the contrary: the same object appears to be of the same color even
under different illuminations.
This is known as color constancy. It is also known that the human visual
system corrects for the prevailing scene illumination [9], [10].
However, for digital cameras, this is a challenging engineering problem
<Challenges in Automatic White Balancing>
- Automatic White Balancing in Digital Photography http://goo.gl/I07BX7
作者: tyf99 (呵呵)   2013-10-14 03:22:00
如果有一張能記錄完整光譜的理想照片,你認為需要AWB嗎?第二,白紙在白光下是白色,在紅光下是紅色,何者有色偏?實際上,這兩者都沒有色偏,都不需要調WB只有在轉成RGB,猜錯光源、套用錯誤的偏移時,才會產生色偏至於相機顏色是否要跟人眼所見一致,用一個簡單的例子來說:假設某物體在某光源下,被相機捕捉到綠色在同時,某甲的肉眼看到的是紅色那麼相機該存成什麼色,綠色或是紅色?假設相機存成綠色,螢幕放綠色照片,甲是否會看成紅色?假設相機改存紅色,螢幕放紅色照片,甲是否仍會看到紅色?至於你說的暖色調冷色調傾向,那只是不同廠牌的調色喜好"我認為tyf99是把如D65光源當成物體的標準色" 這是你的誤解我的觀點是,若相機捕捉到的是波長A的光,檔案存成A就對了當然以目前科技來說,相機無法分辨波長,只能存R/G/B用RGB三種波長去混出A的色彩,其標準為何,模擬人類嗎?人的色盲程度輕重不一,我看到的黃色不見得跟你的黃色一樣相機要以誰的眼睛當標準?或是找幾千人來測試取個平均值?

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