Proposal of a 2D Image-Based Human Body Measurement Protocol

Ye Eun Kim^*, Jiyoung Choi, Hee Eun Choi^†

¹ Department of Fashion and Textiles, Seoul National University, Republic of Korea

Research Institute of Human Ecology, Seoul National University, Republic of Korea

^† Department of Fashion and Textiles, Seoul National University, Republic of Korea

  There is a growing interest in anthropometric measurement and size recommendation technologies utilizing 2D imagery. While these technologies offer high portability and accessibility, issues regarding projection distortion and contour occlusion—caused by varying shooting conditions and physical characteristics—remain significant impediments to ensuring reliability. These distortions are particularly pronounced in muscular physiques, exacerbating measurement difficulties. Consequently, this study validates the effectiveness of a 2D image measurement protocol specifically for muscular males and proposes concrete measures to mitigate its limitations.

For this study, subjects were recruited from a pool of 220 Special Forces personnel, a group distinctively characterizing the muscular somatotype. A primary screening selected individual meeting a quantitative chest circumference criterion of 103–106 cm. From this subset, 15 participants exhibiting a "Y-shape" physique—representative of significant contour occlusion due to muscular development—were ultimately selected via expert visual assessment. Full-body images were analyzed using a standard protocol designed to minimize projection distortion (2 m distance, 100 cm camera height).

Figure1. Configuration of the image acquisition setup for anthropometry

  To verify protocol stability, subjects were divided into three groups based on height tertiles derived from the original population (159.5–170.4 cm, 170.5–175.2 cm, and 175.3–189.4 cm).

Figure 2. Photography protocol and landmark definitions

  One-way ANOVA results indicated no significant differences among height groups for most variables, including chest width (F=1.379, p=.289), waist width (F=1.504, p=.261), and thigh width (F=0.015, p=.985). This confirms that the standard protocol is applicable with stability regardless of subject height. Although ankle thickness ratio showed the only significant difference between groups (F=9.253, p=.004), a comparison with 3D scan data revealed no significant difference for the same variable (F=1.869, p=.197). This identifies the discrepancy as a systematic distortion attributable to the shooting conditions rather than an actual morphological difference.

  Addressing these systematic distortions and the contour occlusion inherent in muscular physiques, this study refined the measurement protocol. For frontal measurements, where latissimus dorsi and arm muscle development often distort upper body width, the use of a wrist spacing guide with a minimum width of 20 cm is proposed. For lateral measurements, to secure clear contours of the waist, hips, and thighs, a posture involving 90° shoulder flexion and 90° elbow flexion (placing hands in front of the chest) was found effective. However, as this posture induces a mean error of 3.31% reduction in chest depth compared to the standard standing posture, a "segment-specific measurement approach" is recommended: chest dimensions should be measured in the standard posture, while the waist, hips, and thighs are measured in the raised-arm posture.

  This study is significant in that it not only demonstrates the utility and stability of the standard 2D image measurement protocol but also clearly identifies technical limitations arising from the specific conditions of muscular physiques and provides concrete methodological solutions.