Performance Analysis: Modern Warfare 3

In our review of Microsoft's E3 press conference, we addressed claims from Infinity Ward that Modern Warfare 3 is "locked" at 60FPS, based on observations from the gameplay showcased at media briefing. Our conclusion? The game still dropped frames, but did a very good job in maintaining a perceptual 60Hz update.

The man who made the original claims is non-other than Infinity Ward's creative strategist, Rob Bowling, who was also the guy playing the game on stage. He recently tweeted that MW3 "will be locked at 60 FPS which means it will never go below it... it can always go above 60 FPS."

There's perhaps a bit of confusion here. Call of Duty games are v-synced - put simply, each time the display is refreshed, a new frame is piped through to the screen. If the frame completes rendering before the refresh, the system waits for your display to catch up. In short, the game physically can't run faster than 60FPS without introducing screen-tear, and we really don't want to go there in a console COD game.

So just how smooth is Modern Warfare 3? We managed to acquire a 60Hz source of the Microsoft event and processed the footage with our analysis tools. The results affirm our initial observations that gameplay is indeed very, very smooth with just the odd drop in performance - only really noticeable to the human eye when the crashing waves overwhelm the player's viewpoint. Of course, the game is still in development, so there is still the opportunity for further optimisations to be made, but even in the here and now, the E3 code is an impressive performer.

Now for the technical minutiae, kicking off with the obvious question of where we got a 60Hz source, bearing in mind that all the internet video streams were 30FPS only. The answer is found in the watermark - a 1080i off-air TV recording of Gametrailers/SpikeTV's excellent coverage of the E3 event not only provided the very best picture quality, but also the required temporal resolution too.

1080i video still runs at 30 frames per second, but because of the interlaced fields, 60Hz worth of action is included in each frame. With a bit of video processing magic, we were able to de-interlace the video, separate the fields and give us back the required 720p60 source. As the video was derived from a compressed stream rather than the pristine nature of a direct HDMI capture, the analysis was then checked by eye on a frame-by-frame basis to ensure accuracy. This time-consuming process is required because video compression artifacts in fast motion scenes can be seen by our tools as unique frames, distorting the results.

Yes, that took a long time but the results were worth it. While the "locked" 60FPS claims don't quite pass muster, this is still a storming performance from the developers: a technical achievement that translates directly into a better gameplay experience for the player. If Infinity Ward and Sledgehammer Games can sustain this performance level throughout the game, we would be looking at the smoothest Call of Duty console title since the original Modern Warfare on Xbox 360. Bearing in mind how essential the high frame-rate and crisp response is to the core of how COD plays, that would be very, very good news indeed.