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56 lines
1.8 KiB
HTML
<html><head><link rel="stylesheet" href="style.css"></head><body><div class="page">
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<h1>20100104 - OnLive Notes</h1>
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<br>
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<pre>Notes from an OnLive Video Demonstration and Talk ...
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LATENCY
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=======
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They target 80ms round trip interactive latency
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for 1000 mile range from data center.
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From rough numbers given in talk and other estimation,
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11 ms - Round trip of 2000 miles (speed of light).
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21 ms - Round trip, in practice.
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25 ms - Round trip (+DSL/Cable provider overhead).
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01 ms - Encode frame.
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08 ms - Decode frame (example from laptop).
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33 ms - Maxed out 30Hz frame in game.
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12 ms - Client side input latency and misc.
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-----
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80 ms - Total.
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VIDEO COMPRESSION
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=================
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About 1 ms to compress a frame: 1.5 Mbps SDTV, 5 Mbps HDTV.
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In comparison DVD maximum rate for audio+video is 10 Mbps and Blu-ray is 48 Mbps.
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The 5 Mbps seems like really low quality from the numbers alone.
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No GOP, probably just I and P without B frames.
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Comments from Dark Shikari suggests OnLive is simply splitting encoding
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into 16 independent rectangular tiles and using H.264
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as the method to bring encoding latency down.
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NETWORK ROUTING
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===============
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Problems with home internet include jitter, packet loss, reordering,
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and routers delaying packets to check for exploits.
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They have deals with ISPs to provide direct routes on internet to minimize latency
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and have tree structured ip-multicast to enable efficient 100K spectators
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(1000 per multicast stream).
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BREAKDOWN OF TYPICAL GAME COST
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==============================
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From the talk (they also include extra costs: $12/game piracy, $12/game used game sales):
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$15 - Retail margin.
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$18 - Wholesale ($7 returns, $4 COGS, $7 platform royalty).
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$27 - Publisher gross margin.
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---
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$60 - Total.</pre>
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