OpenCL In Action: Post-Processing Apps, Accelerated

Test Setup And Benchmarks

In planning this series, we asked ourselves what readers really need to know about exploiting DirectCompute/OpenCL acceleration. Is it difficult? No. The drivers enable functionality by default, and most applications able to leverage the improvements have what amounts to an on/off switch to either use the feature or not. We’re stumped as to why anyone would disable acceleration, but it does make our job of testing the features much easier.

Right out of the gate, we're testing two OpenCL-enabled post-processing applications: ArcSoft’s Total Media Theater (TMT) 5.2 (in pre-release at our time of testing) and MotionDSP’s vReveal.

The SimHD component of TMT now uses OpenCL and GPU-based processing to interpolate standard-definition video (480p) to near-HD levels (720p) in real-time. To test this, we played a DVD copy of Minority Report with (GPU) and without (CPU) OpenCL enabled. We ran in comparison split-screen mode with SD on the left half of the image and near-HD on the right half. ArcSoft provides four main features within SimHD—upscaling, dynamic lighting, denoise, and smoothness—but we only tested with the first three enabled and set to maximum. The smoothness option was not available when testing in a CPU-only processing scenario, so we omitted it to have consistency across our test parameters. Also, we only tested SimHD with AMD's Radeon HD 5870 because, as of our testing, Total Media Theater wouldn't cooperate with AMD's Radeon HD 7970. That's not surprising, considering we also had trouble getting GPU-accelerated compute working in CyberLink's Media Espresso in our AMD Radeon HD 7950 Review: Up Against GeForce GTX 580 coverage.

MotionDSP’s vReveal gained fame as one of the first and best consumer-oriented applications for fixing shaky video. The amount of processing required to pull this effect off in real-time is formidable, since several frames of video must be analyzed at once and, many features tracked and recompiled across those frames. At 1080p, this load can cripple some systems. Today, vReveal 3 also includes several additional features, including sharpening, brightening, and noise cleaning, all of which can run concurrently with stabilization. Ideally, you'd have all of this rendering in real-time.

In our tests, we used two sample video clips that ship with the downloadable binary of vReveal 3: the “Barcelona” file at 480p and the “San Francisco” file at 1080p. We tested these twice, once with only basic stabilization enabled and then in a more demanding configuration with five effects piled on. We then tested these in CPU-only, APU-accelerated, and two different discrete GPU-based configurations.