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Measuring Input Latency In Console Games
The Digital Foundry blog has an article about measuring an important but often nebulous aspect of console gameplay: input lag. Using a video camera and a custom input monitor made by console modder Ben Heck, and after calibrating for display lag, they tested a variety of games to an accuracy of one video frame in order to determine the latency between pressing a button and seeing its effect on the screen. Quoting:
"If a proven methodology can be put into place, games reviewers can better inform their readers, but more importantly developers can benefit in helping to eliminate unwanted lag from their code. ... It's fair to say that players today have become conditioned to what the truly hardcore PC gamers would consider to be almost unacceptably high levels of latency to the point where cloud gaming services such as OnLive and Gaikai rely heavily upon it. The average videogame runs at 30fps, and appears to have an average lag in the region of 133ms. On top of that is additional delay from the display itself, bringing the overall latency to around 166ms. Assuming that the most ultra-PC gaming set-up has a latency less than one third of that, this is good news for cloud gaming in that there's a good 80ms or so window for game video to be transmitted from client to server."
It may be that console gamers have learned to expect around 100-150ms of input latency, perhaps thanks to visual cues that help to justify the latency on some level. (If I decide to jump, it takes a certain amount of time to react to my thought and make that happen; if I tell Mario to jump, maybe he takes about the same amount of time to react to the stimulus. It makes a certain kind of sense.)
But I assure you that musicians find that level of latency unacceptable. When you're playing a software synth live, performing with other musicians, even 75ms of latency is very noticeable and makes you feel like you're playing through molasses. Same thing with recording -- if it takes longer than 25-30ms to hear my own sound coming back at me, I definitely notice it. Virtuosic music regularly exceeds an input density of 50ms per event!
One thing Rock Band has done, and presumably this came from somewhere else or has propagated to Guitar Hero and other rhythm games, is that you can set the video latency and audio latencies separately and finely tune the system so that it looks and sounds like you want it to be.
Rock Band 2's guitar controller actually has a tiny light sensitive component and a cheap microphone, so that you can auto-set your game. It's really very handy, and took only fifteen seconds or so. The result was that when a note crosses the "active line" of the game is when I should both strum it / hit it / sing it and hear the result.
Are you certain there is no way to do the same thing with DDR?