Discrete HTPC GPU Shootoutby Ganesh T S on June 12, 2011 10:30 PM EST
Mismatches in the display refresh rate and source frame rate are difficult to spot for the average HTPC user, particularly if the dropped or repeated frames are far apart. Bad deinterlacing performance, on the other hand, may easily ruin the HTPC experience even for the average user. From DVDs to recorded TV shows and even Blu-ray documentaries, interlaced content is quite common.
We have been using the Cheese Slices test to check up on deinterlacing performance in the past. Instead of just covering the cheese slice alone, we will present a set of four consecutive deinterlaced frames from the video for you to judge.
Before presenting the results, let us take a look at how the ideal deinterlacing output should look like (a screenshot from the progressive version of the Cheese Slices clip around the same timestamp)
Click for Lossless Version
NVIDIA GT 430 Cheese Slices Deinterlacing:
MSI GT 520 Cheese Slices Deinterlacing:
AMD 6450 Cheese Slices Deinterlacing:
MSI 6450 Cheese Slices Deinterlacing:
Sapphire 6570 Cheese Slices Deinterlacing:
The Cheese Slices test is an artificial test clip. To bring some real world perspective to the deinterlacing performance, let us take a look at some screenshots of the 'Ship' clip from the Spears and Munsil High Definition Benchmark Test Disc (hereon referred to as the S&M clip). It is supposed to test the edge adaptive deinterlacing capabilities of the GPU. Note the jaggies in the various ropes in the screenshot. Roll the mouse over the various GPUs in the list below the image to see how each candidate performs.
|MSI GT 520||MSI 6450||NVIDIA GT 430||Sapphire 6570|
Pay particular attention to the deinterlacing performance of the GT 520. Compared to the other 4 cards in the test, this one emerges as the worst of the lot in the Cheese Slices test as well as the real world video test. When this was brought to NVIDIA's attention, they indicated the lack of shaders on the GF119 as the main reason for this issue. It looks like driver updates are not going to solve the issue in the future either. This is a big letdown for the prospective customers of the GT 520. Even though the deinterlacing performance of the GT 430 looks pretty good, a closer look reveals that it is not as effective as AMD's vector adaptive deinterlacing strategy.
On the AMD side, it looks like the reduced core clock frequency and lessened DRAM bandwidth of the MSI 6450 doesn't affect the deinterlacing performance in the Cheese Slices test. Vector adaptive deinterlacing works across all the cards in the 6xxx lineup. However, AMD has admitted to some driver issues for local file playback in the DDR3 based 6450s. This is probably the reason for the bad performance of the MSI 6450 in the S&M ship clip above. In an informal blind test, a majority seemed to prefer the 6570's output in the clip above, but you can decide for yourself.
The Catalyst Control Center allows users to experiment with different deinterlacing algorithms, while NVIDIA's Control Center doesn't. Admittedly, this choice of deinterlacing algorithms is of academic interest only. That said, the bad deinterlacing performance of the GT 520 and the fact that it is not going to improve in the future forces us to declare AMD the winner in this area.