The Elemental Accelerator is a plugin for Adobe Media Encoder CS4 that harnesses the computing power of high end NVIDIA Quadro GPUs to encode video files faster. It currently supports output to DVD, Blu-Ray, and a variety of other MPEG2 and H.264 formats. Besides decreasing the time required to export and encode a file, it frees up the CPU for other tasks, so ideally you can continue working while your file is exported, with minimal impact on available performance. As a side benefit, the encoder includes an option to create 5.1 channel surround AC3 files for DVD and BluRay, which is not otherwise an option in Adobe Media Encoder.
The first version of the accelerator was released last spring, but was very limited in its scope. It only created H.264 files, the surround sound options were not fully functional, and it only worked with the Quadro CX. They are now on version 2.1 and have added acceleration for MPEG2 encoding, support for accelerated effects processing when exporting timelines from Premiere Pro CS4, fixed the audio issues, and open up support to include six other NVIDIA GPUs. This includes two mobile chips, so the accelerator can run on laptops as well. The first Macintosh version was also recently released, utilizing the new QuadroFX 4800 for Mac.
NVidia and Elemental Technologies report that the accelerator can provide up to a 10x increase in encoding speeds, but mileage may vary in real world use. With my system, I usually found encoding rates to be 50% to 100% faster with real world work, depending on the output settings, which is still a significant improvement if you do a lot of exporting. The relative increase in encoding performance that you will experience depends on the speed of your system. Older systems will see a major improvement, while newer high end workstations are already quite fast, so the change will be less dramatic. My 3Ghz 8-Core workstation can already encode my HD timelines to MPEG2 for DVD faster than realtime, but with the Elemental Accelerator, I was able to cut the time for a two minute export from 1:27 to 30 seconds. On a two hour clip, that would be a thirty minutes instead of an hour and a half. My 1080p H.264 encodes for BluRay output only saw a 50% increase in encoding speed.
Exports of more complicated timelines see less of an improvement because render speed is not accelerated by the GPU as much as encoding speed is. If you coming from a single flat clip, the increase in export speed will be much more apparent. I don’t use AVCHD footage, but when encoding from those types of source files, the GPU can accelerate the processing intensive AVCHD decode, as well as the MPEG2 or H.264 encode. This should lead to more dramatic performance improvements, especially on laptops, where available CPUs are not as powerful as their desktop counterparts. When I first reviewed the accelerator software earlier in the year, I anticipated that laptops would be even better served by a GPU based accelerator than desktops. If you frequently make these types of exports from a laptop with a Quadro GPU, this plugin will be worth it. In the desktop world it isn’t as simple, since the CPUs are not so weak by comparison to the GPU. If you make DVDs or BluRays for a living it will be a no brainer, but otherwise it all depends on how much of your day you spend waiting for exports to complete.
There are still a few other issues to be worked out. The Adobe Media Encoder CS4 is designed to minimize the decrease in system performance during background rendering by pausing exports during timeline playback. This may be necessary on lower end systems, but eight-core workstations should have power to spare, before we even factor in the GPU. This prevents Adobe Premiere CS4 from really utilizing the CPU power being freed up by the GPU acceleration, because any time it is called upon, the render gets paused anyway. Adding the option to disable that functionality would be beneficial to both Elemental Accelerator users, and anyone else with a high-end workstation, so that they could truly multi-task their system. Until then, its probably best to work outside of Premiere Pro during your accelerated exports, to truly take advantage of your available system power.
With NVIDIA’s Digital Video Pipeline in the works, its easy to see where this could be going. Once they have SDI video inputs available, we could see realtime capture directly to H.264 and MPEG2 files, among many other things. With professional I/O, the available GPU power could be used to turn the video card into a full editing accelerator card. With SLI Mosaic and other new developments with the QuadroPlex, I can see it being scaled up to 4K frame sizes with realtime performance, and I am definitely looking forward to that.