Colour-reproduction algorithm for transmitting variable video frames and its application to capsule endoscopy

[摘要] Presented is a new power-efficient colour generation algorithm for wireless capsule endoscopy (WCE) application. In WCE, transmitting colour image data from the human intestine through radio frequency (RF) consumes a huge amount of power. The conventional way is to transmit all R , G and B components of all frames. Using the proposed dictionary-based colour generation scheme, instead of sending all R , G and B frames, first one colour frame is sent followed by a series of grey-scale frames. At the receiver end, the colour information is extracted from the colour frame and then added to colourise the grey-scale frames. After a certain number of grey-scale frames, another colour frame is sent followed by the same number of grey-scale frames. This process is repeated until the end of the video sequence to maintain the colour similarity. As a result, over 50% of RF transmission power can be saved using the proposed scheme, which will eventually lead to a battery life extension of the capsule by 4–7 h. The reproduced colour images have been evaluated both statistically and subjectively by professional gastroenterologists. The algorithm is finally implemented using a WCE prototype and the performance is validated using an ex-vivo trial.

[学科分类] 肠胃与肝脏病学

[关键词] endoscopes;biomedical optical imaging;medical image processing;image colour analysis;image sequences;colour-reproduction algorithm;wireless capsule endoscopy;dictionary-based colour generation scheme;grey-scale frames;gastrointestinal diagnosis;human intestine;colour image data transmission;variable video frame transmission;video sequence;colour similarity