GPU encoding comparisons, plus conclusionHere are the same 720p YouTube outputs, but now encoded using the GPU.
It should be noted, however, that the final image quality of the GPU-accelerated output file varies hugely, dependent on the source footage fed into MediaShow Espresso. This was made blatantly obvious when we analysed the image quality of the output files created from a different HD feed. AMD came up trumps by offering a much cleaner (albeit slightly softer) output than the NVIDIA's.
Although this is just one example of a GPGPU application from the increasing number that are now available, it’s clear to see from the results that not only is there a marked performance difference, but also a marked difference in image quality: and both are dependent upon the actual HD footage used.
Sometimes AMD-produced video is better, other times, as per the screenshots, NVIDIA's is better. Additionally, CyberLink’s MediaShow Espresso doesn’t allow enough flexibility to achieve the best compromise between file-size and image quality. To make matters worse, at least with both of the MPEG-2 1080p video clips we fed it, it would only output with an incorrect 29fps frame-rate, instead of the input files 25 fps frame-rate.
GPGPU encoding is a nascent but burgeoning sector that will develop over time. The intrinsic benefits of massively parallel processing are obvious, and the results show that high-end cards can beat out any consumer CPU with consummate ease. Taken with CyberLink's MediaShow Espresso software as a base, we'd recommend that users opt for a program with significantly better encoding quality and speed.