A Keyframe Selection of Lifelog Image Sequences

Visual lifelogging is a new concept of recording one’s daily life by using wearable camera to automatically capture images of one’s surroundings. Keyframe selection is a crucial process for summarizing lifelog image sequences. In the visual lifelog domain, images are passively captured in predefined time intervals, e.g. one image every 30 seconds. This results in variable visual quality in the image sequences. Contrary to videos, two consecutive frames are not necessarily similar in lifelog sequences. Thus, video processing techniques are not directly applicable. We propose a keyframe selection technique based on measuring image quality and distance to the middle frame. Based on the proposed evaluation framework, 81.6 % of keyframes selected by our approach are accepted, whereas only 70.4 % are accepted when using the middle frames as keyframes. Additionally, Ground Truth (GT) keyframes are investigated in terms of image quality and the position in time relative to their events. This provides information about their distributions and explain the results.