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通过数据包损失降低的V-PCC压缩动态点云的主观质量评估
Emil Dumic1, Luis A da Silva Cruz2,3
1Department of Electrical Engineering, University North, 104. Brigade 3, 42000 Varaždin, Croatia.
Sensors (Basel, Switzerland)
|July 8, 2023
概括
压缩动态点云中的信息丢失显著影响感知质量. 即使是微小的数据包丢失 (0.5%),也会大大降低主观质量,强调需要强大的比特流保护. 占用和几何数据是最脆弱的.
科学领域:
- 计算机视觉 计算机视觉
- 多媒体压缩压缩.
- 数据传输 数据传输
背景情况:
- 动态点云越来越多地用于沉浸式应用.
- 压缩对于高效的传输和存储至关重要.
- 在传输过程中信息丢失可能会降低重建的点云质量.
研究的目的:
- 实证地研究信息丢失对压缩动态点云质量影响.
- 在不同的压缩和数据包丢失条件下评估重建的点云的主观质量.
- 将主观质量评分与客观质量指标相关联.
主要方法:
- 动态点云使用MPEG V-PCC编码器压缩在5个级别.
- 模拟的数据包损失为0.5%,1%和2%,适用于子比特流.
- 主观质量通过人类观察员在两个实验室的平均意见分数 (MOS) 来评估.
- 对MOS分数的统计分析和与客观质量指标 (FSIM,MSE,SSIM,PCQM) 的相关性.
主要成果:
- 0.5%的数据包丢失率使主观质量降低了1-1.5个MOS单位.
- 基于图像的指标 (FSIM,MSE,SSIM) 和PCQM显示与主观得分有很高的相关性.
- 占用和几何子位流的退化比属性子位流的退化产生了更大的负面影响.
结论:
- 动态点云比特流需要足够的保护,防止数据包丢失.
- 客观质量指标,如PCQM和适应的图像指标,可以有效地预测主观质量.
- 优先保护占用和几何数据对于保持感知质量至关重要.
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