《昨日的世界》為香港藝術家高倩彤於2017年的雙頻道影像創作。作品隨著一張自維基百科上搜尋到有關視訊顯示格式1080p（FULL HD）的圖像逐漸展開。圖像分別以紅色、藍色及彩色標示個別視訊顯示格式，呈現出不同解像度的大小及比例差異，而以彩色代表著高清規格正如同暗示著此乃通往真實的正確途徑。

高倩彤以此圖像為開端，依尋著技術性的描述方法，將紅色表述為肉眼可見的世界，藍色表述為內部思考的世界，各自依據著紅色和藍色的範疇揉雜入藝術家自行拍攝的片段，遵循著一種圖像規則的姿態解構人們看待世界的方式，提問著種種關於時間、速度、適應、變化的思考。

在高倩彤的作品中，可以看見他的意志如何在幾個不同色塊的圖像平面間穿梭，透過感性的路徑與詰問的絮語，編織了個人化的視覺景觀，抵抗技術所帶來的景觀結構系統，強化了對於真實外在的認知始終來自於個人的想法。

The world of yesterday is a two-channel video work by Ko Sin Tung in 2017. The work gradually unfolds with an image about video display formats of 1080p (Full HD). The images are displayed in red, blue, and colors to mark the different video display formats, presenting in different resolution sizes and ratios. The one in colors represents High Definition, which implies the right path to the truth.

Ko Sin Tung departs from this image and follows the technical description’s approach to express red as the world visible to the eyes, and blue as the world of internal thinking. The footages shot by the artist are infused according to the definitions of red and blue, in pursuant to a posture of image rule to deconstruct the way people see the world, inquiring the thinking about time, speed, adjustment, and variation.

In the work of Ko Sin Tung, one can see how her will traverses between images of different colors. Through emotional route and inquisitive whisper, it weaves out a personalized visual landscape, resisting the structural system of landscape brought by technology while reinforcing the recognition of the true appearance that comes always from the thoughts of individual.