Multiple sketch datasets have been proposed to understand how people draw 3D objects. However, such datasets are often of small scale and cover a small set of objects or categories. In addition, these datasets contain freehand sketches mostly from expert users, making it difficult to compare the drawings by expert and novice users, while such comparisons are critical in informing more effective sketch-based interfaces for either user groups. These observations motivate us to analyze how differently people with and without adequate drawing skills sketch 3D objects. We invited 70 novice users and 38 expert users to sketch 136 3D objects, which were presented as 362 images rendered from multiple views. This leads to a new dataset of 3,620 freehand multi-view sketches, which are registered with their corresponding 3D objects under certain views. Our dataset is an order of magnitude larger than the existing datasets. We analyze the collected data at three levels, i.e., sketch-level, stroke-level, and pixel-level, under both spatial and temporal characteristics, and within and across groups of creators. We found that the drawings by professionals and novices show significant differences at stroke-level, both intrinsically and extrinsically. We demonstrate the usefulness of our dataset in two applications: (i) freehand-style sketch synthesis, and (ii) posing it as a potential benchmark for sketch-based 3D reconstruction. Our dataset and code are available at https://chufengxiao.github.io/DifferSketching/.
翻译:提出了多个素描数据集,以了解人们如何绘制 3D 对象。然而,这些数据集往往规模小,覆盖了一组小对象或类别。此外,这些数据集包含主要由专家用户提供的免费草图,因此很难比较专家和新用户的图纸,而这种比较对于为任一用户群体提供更有效的素描界面至关重要。这些观测激励我们分析拥有和没有适当绘制技能的3D 对象的人有多么不同。我们邀请70个新用户和38个专家用户素描136 3D 对象,这些天体是由多种观点提供的362张图像提供的。这导致一个新的数据集有3,620个自由手多视图素描,在特定观点下与相应的3D 对象一起登记。我们的数据集是一个比现有数据集大得多的量级。我们从三个层次分析收集的数据,即素描、中、中、和像素描等级别,在空间和时间特征下,以及在创作者群体内部和相互之间,我们发现专业人员和新手动的图纸图纸- 显示我们手动/ 水平上的潜在价值。我们手动/手动图的深度分析中,我们手动/手动/手动的图表在水平上显示了我们手动/手动的手动/手动/手动图上,在手动的图上,在手动/手动/手动上,在手动轴上显示了我们手动/ 水平上和手动的图的图上,在手动/手动/手动的图上,在手动的图上,在手动/手动。我们做了上,在手动/手动的图的图上,在手动。我们做了上显示了手动/手动的深度和手动的图上显示了。