针对传统的视频质量评估模型对于在包交换网络中传输的压缩视频（网络视频）进行质量评估的局限性，如对视频质量进行评估时实时性差、没考虑人眼的视觉感知等问题，提出了一种基于网络丢包的网络视频质量评估模型。该模型采用了统计学理论，它可根据视频编码、封装传输的特点，通过可量化的评价指标来评定视频质量受网络丢包的影响程度，以评估网络视频质量。利用该模型进行网络视频质量评估，不仅资源开销小、实时性好，而且特别适合对实时传输的视频流进行视频质量评估。为了验证该模型的正确性与可靠性，采用它与MPQM模型分别对受系列丢包率影响的视频序列进行了评估实验。实验结果表明，该模型的评价结果能较好地吻合MPQM模型的评价结果，且符合人眼的视觉效果。

To solve the limitation of the traditional evaluating models of video quality in accessing the quality of video over a packet network, such as unsuitable for on-line usage, not considering human visual perception, this paper introduces a video quality evaluating model based on packet loss. This model, which is inferred based on the statistics theory, can access the video quality over a packet network with a quantitative index according to the characteristics of video coding, packetiing and translation. It consumes little computing resources in quality evaluation and is suitable for real-time applications. In order to demonstrate the feasibility and accuracy of this model the simulations and experiments utilize this model and MPQM model, which objectively assesses video quality based on human visual properties, to evaluate a series of video sequences distorted with different packet loss rates and contrast their evaluation values. The experimental results have shown that the evaluation values of this model are approximately equal to MPQM values and reflect human visual perception.