A novel evaluation study of the most appropriate round function for nearest-neighbor (NN) image interpolation is presented. Evaluated rounding functions are selected among the five rounding rules defined by the Institute of Electrical and Electronics Engineers (IEEE) 754-2008 standard. Both full- and no-reference image quality assessment (IQA) metrics are used to study and evaluate the influence of rounding functions on NN interpolation image quality. The concept of achieved occurrences over targeted occurrences is used to determine the percentage of achieved occurrences based on the number of test images used. Inferential statistical analysis is applied to deduce from a small number of images and draw a conclusion of the behavior of each rounding function on a bigger number of images. Under the normal distribution and at the level of confidence equals to 95%, the maximum and minimum achievable occurrences by each evaluated rounding function are both provided based on the inferential analysis-based experiments.

翻译：本文提出了一项关于最近邻（NN）图像插值中最合适舍入函数的新颖评估研究。所评估的舍入函数选自电气和电子工程师协会（IEEE）754-2008标准定义的五种舍入规则。研究采用全参考与无参考图像质量评估（IQA）指标，以分析和评估舍入函数对NN插值图像质量的影响。通过“达成频次相对于目标频次”的概念，依据所用测试图像数量确定达成频次的百分比。应用推断统计分析，旨在从少量图像样本中推导结论，以推断各舍入函数在更大规模图像集上的表现行为。在正态分布假设及95%置信水平下，基于推断分析实验，同时给出了每种受评估舍入函数可达到的最大与最小可能频次。