Struct Ft8StreamDecoder 

pub struct Ft8StreamDecoder { /* private fields */ }

Accumulates IQ samples at 12 kHz and decodes FT8 or FT4 frames.

Feed samples incrementally with [feed]. When the internal buffer reaches frame_len samples, a decode attempt is triggered automatically and the results are returned. Call [flush] to attempt a decode on whatever is currently buffered (useful at the end of a session or after a gap). Call [clear] to discard the buffer without decoding.

The decoder operates at the FT8/FT4 native sample rate of 12 000 Hz. Callers receiving samples at a higher rate (e.g. 48 kHz) must decimate before feeding.

A single CallsignHashTable is maintained across frames so nonstandard callsigns hashed in earlier frames can be resolved in later ones.

Implementations

impl Ft8StreamDecoder

pub fn new_ft8(fs: f32, base_hz: f32, max_hz: f32, max_cand: usize) -> Self

Create a decoder for FT8 frames.

• fs — sample rate (should be 12 000 Hz)
• base_hz — lowest tone-0 frequency to search (Hz)
• max_hz — highest tone-0 frequency to search (Hz)
• max_cand — maximum sync candidates to score per decode attempt

pub fn new_ft4(fs: f32, base_hz: f32, max_hz: f32, max_cand: usize) -> Self

Create a decoder for FT4 frames.

pub fn feed(&mut self, iq: &[C32]) -> Vec<Ft8DecodeResult>

Feed IQ samples into the accumulation buffer.

If the buffer reaches frame_len samples after appending, a decode attempt is triggered and the results are returned. Otherwise returns an empty Vec.

pub fn flush(&mut self) -> Vec<Ft8DecodeResult>

Attempt a decode on whatever is currently in the buffer.

Useful at a gap edge when the caller knows a frame has ended but the buffer may be shorter than frame_len (e.g. due to signal dropout). Returns decoded results; does NOT clear the buffer.

pub fn clear(&mut self)

Discard all accumulated samples without decoding.

pub fn len(&self) -> usize

Number of accumulated samples.

pub fn is_empty(&self) -> bool

True if no samples have been accumulated.

pub fn view_buf(&self) -> &[C32]

Read-only view of the accumulated IQ buffer.