The number of samples prior to the current sample, in decode order, the decoder requires in order to achieve a coherent output at the current decode time.
- macOS 10.11+
Zero is returned when no samples are required for decoder refresh or when the track does not contain this information.
Some sample sequences do not indicate sample dependencies and instead indicate that in order for a specific sample to be decoded with all available accuracy. Samples prior to that sample in decode order must be decoded before the specific sample is decoded.