fix to avoid recreating imageData buffer on every frame
fix to avoid recreating imageData buffer on every frame

chrislearn/ogv.js,xzf158/ogv.js,xzf158/ogv.js,chrislearn/ogv.js,xzf158/ogv.js,chrislearn/ogv.js,paladox/ogv.js,paladox/ogv.js,paladox/ogv.js,paladox/ogv.js,xzf158/ogv.js,paladox/ogv.js,chrislearn/ogv.js,xzf158/ogv.js,chrislearn/ogv.js