struct snd_compr_tstamp {
  __u32 byte_offset;
  __u32 copied_total;
  __u32 pcm_frames;
  __u32 pcm_io_frames;
  __u32 sampling_rate;
};  

Byte offset in ring buffer to DSP

Total number of bytes copied from/to ring buffer to/by DSP

Frames decoded or encoded by DSP. This field will evolve by large steps and should only be used to monitor encoding/decoding progress. It shall not be used for timing estimates.

Frames rendered or received by DSP into a mixer or an audio output/input. This field should be used for A/V sync or time estimates.

sampling rate of audio