“Illustration timelapse videos” and “illustration making videos” that record the drawing process of digital illustrations are widely viewed for learning and appreciation purposes. However, since many videos simply record the shortened drawing process as is, it takes time and effort to focus on specific parts of the illustration and observe the process.
In this research, we propose a learning analysis tool that displays parallel timelines for each region showing temporal changes of areas of interest, allowing users to confirm the drawing process by clicking. We also propose a method for enjoying more interactive timelapse using the data obtained from this analysis.
Analysis Tool for Illustration Learners
This tool was developed to efficiently analyze the illustration drawing process. The upper part of the screen displays the timelapse video, the center shows an enlarged image of the focused area, the right side shows difference images, and the bottom displays parallel timelines visualizing temporal changes of features for each region using color maps.
Users specify regions of interest as mask images from the completed illustration in advance, and extract inter-frame differences of each region as features. Blue areas on the timeline indicate periods with little change, while green, yellow, and red colors indicate increasingly active drawing periods. Users can click on the timeline to confirm the drawing process at that time. This enables efficient learning focused on specific parts such as character faces and eyes.
More Interactive Timelapse Generation
Each region in an illustration generally has long periods without visual changes, so when playing back along the original timelapse timeline, individual regions of interest show little visual variation.
Therefore, we generate independent timelapse videos for each region, removing frames without changes. Furthermore, we create timelapse videos with consistent visual change rates by using narrow sampling intervals for areas with frequent changes and wider intervals for areas with fewer changes.
We recompose these region-based timelapse videos back into the original illustration and implement an interactive exhibition that responds to viewers’ gaze and touch operations to rewind the timelapse. This enables focused viewing of the drawing process for areas of interest and is expected to stimulate viewers’ interest in the illustration creation process.
Acknowledgments
The timelapse video used as an example in this work was used with the permission of the copyright holder as follows:
Zofia Duffy: teahouse ✦ timelapse【CLIP STUDIO PAINT】 https://youtu.be/uzM64vRR2dg
We would like to thank Zofia Duffy for granting permission to use the video.