Although there are many apps available for OS X that can perform video encoding using the x264 codec, and therefore little reason to use a Windows-based encoder via a virtual machine, the x264 encoding process is extremely CPU-heavy, and serves as a good benchmark for measuring performance between VMs and native Windows installations.
Our x264 test is based on the popular Handbrake app and encodes a roughly 10-minute clip of the animated short Big Buck Bunny using the default “Apple TV 3” preset. The results are the average frames per second achieved during the encoding process, as reported by the Handbrake log file, with a higher number indicating faster performance.
As was evident from our initial individual looks at Parallels 11 and Fusion 8, both virtualization platforms have nailed it when it comes to video encoding. Our earlier tests showed that Fusion and Parallels were very close to native performance when it comes to purely CPU-bound tasks, but the results here are practically identical to native performance, indicating that you could, if you wanted, use the Windows version of Handbrake in a virtual machine on your Mac and encode video at virtually the same speed as the native Handbrake app for OS X.
The x264 codec tested above is solid, established, and reliable. But that’s not exciting, is it? The future is all about x265, the open source version of the relatively new H.265/HEVC codec. With x265, content creators and consumers can achieve quality levels equivalent to x264, but at a fraction of the bit rate and, thereby, file size. The x265 codec and its commercial counterparts are going to be key to future online delivery of 4K video content, and encoders like Handbrake are already offering basic support. The only problem? x265 encoding and decoding is extremely CPU-intensive, and can bring even the highest-performing CPUs to their knees.
We wanted to see how the latest versions of Parallels and Fusion could handle such an intense workload, and how the free VirtualBox compared. So we turned to the pre-configured x265 Benchmark test to give us an answer. Each encoding test runs five passes and, like the x264 benchmark, reports the average frames per second. You should expect the numbers to be much lower than with x264.
While the overall speed is a fraction of that achieved with x264, the relative results are virtually the same. Fusion 8 practically matches native performance, while Parallels 11 is about 8 percent behind, and VirtualBox safely trails the pack.
As we mentioned, with a host of video encoding options available for OS X, it’s probably not worth running a dedicated x264 or x265 encoder in a virtual machine, even though Fusion and Parallels are both amazingly close in performance. But these results are definitely good news for Mac-owning content creators who may need to use more advanced software that is only available for Windows. In such a case, the user should expect near-native video encoding performance with either Fusion 8 or Parallels 11.