Multi-encoding implies encoding the same content in multiple spatial resolutions and multiple bitrates. This work evaluates the encoder analysis correlations across 2160p, 1080p, and 540p encodings of the same video for conventional ABR bitrates. A multi-resolution tier multi-ABR encoding scheme is modeled and evaluated, which significantly improves the computational efficiency of conventional ABR encoding. Video content is first encoded at the lower resolution with the median bitrate. Encoder analysis decisions, such as motion vectors and CU block structure, are then used in the other encodes in the same resolution tier. The analysis is then extrapolated and refined to be used in higher-resolution encodes. The scheme is validated using x265 HEVC video encoder. The proposed multi-resolution tier multi-bitrate encoding scheme achieves overall speed-ups of up to 2.5x, compared to the conventional single-instance encoding approach. Furthermore, this speed-up is achieved without substantial losses in coding efficiency. SIMD Vector units in CPUs have become the de-facto standard for accelerating media and other kernels that exhibit parallelism. This work also demonstrates the impact of hardware-aware optimizations on the encoding speeds of the next-generation video codecs. The work is evaluated using the Arowana XVC encoder.
翻译:多编码意味着在多个空间分辨率和多位元速率中将相同内容编码。 这项工作评估了2160p、 1080p和540p等常规ABR位速率的同一视频的编码分析相关关系。 建模和评估了多分辨率层多个ABR编码方案, 大大提高了常规ABR编码的计算效率。 视频内容首先在低分辨率中位位位元编码编码。 随后, 在同一分辨率层的其他编码中使用了运动矢量和 CU块结构等编码分析决定。 然后, 该分析被外推和精细用于高分辨率编码。 这个方案使用x265 HIVC 视频编码校验。 拟议的多分辨率层多位数编码方案与常规单级编码编码方法相比,实现了高达2.5x的总增速。 此外, 这一加速速度分析在编码效率方面没有重大损失。 CPU中 SIMD Vectorc 设备已成为更高分辨率编码编码的解析和精度标准。 SADRC 的下级标准 也展示了平行媒体和高级编码的升级工作。