The DPI initialises the WebGL context, the shaders and the DPI pointer. It also parses LCEVC data using the DPI.
There are two ways to parse LCEVC data that are shown in detail in the next sections.
The continiuous way of parsing LCEVC data is used when the video is playing and the last frame has LCEVC data.
LCEVC data needs to be parsed without missing frames, so this function will check if any prior LCEVC data was not parsed and parse that data before moving to the current time. This will maintain an unbroken chain for the temporal buffer.
The key frame way of parsing LCEVC data is used to parse the last key frame or when no LCEVC data has yet been parsed.
LCEVC data needs to parse a key frame in order to parse regular frames so, when losing LCEVC data, this functions needs to be called until a key frame is found.
The function will cover a range of segments in order to find a key frame; from a given time to the current frame. It will start at the earliest time, iterating through the LCEVC data until it finds a key frame or hits the last frame of the specified range.