Struct LiveGstreamerEncoder 

pub struct LiveGstreamerEncoder {
    config: EncoderConfig,
    video_intermediate_path: PathBuf,
    audio_scratch_path: PathBuf,
    video_child: Child,
    video_stdin: Option<ChildStdin>,
    stderr_drain: Option<JoinHandle<String>>,
    audio_writer: BufWriter<File>,
    expected_video_bytes_per_frame: usize,
    frames_pushed: u64,
    audio_chunks_pushed: u64,
}

Live (streaming) video encoder. Spawns the encode pipeline up front and streams BGRA frames into its stdin, so the only video on disk during capture is already compressed. That bounds the scratch footprint to the encoded bitrate instead of the raw firehose (width × height × 4 × fps ≈ 250 MB/s at 1080p, >1 GB/s at Retina) — the prerequisite for capturing at native resolution.

Audio is still buffered to a small raw .f32.scratch (≈0.4 MB/s) and muxed in at finalize via build_remux_args (the video leg is stream-copied, not re-encoded). Keeping audio out of the live pipeline lets the recorder feed a single fd (stdin) with no extra fd plumbing.

Real recording is macOS-only; the pipeline strings are cross-OS so the unit tests + clippy pass everywhere, but the spawn only succeeds where the encoder element + gst-launch-1.0 exist.

Fields

config: EncoderConfig

video_intermediate_path: PathBuf

Compressed video-only intermediate the live child writes to. Remuxed with audio at finalize, then deleted.

audio_scratch_path: PathBuf

Raw F32LE audio scratch — encoded to the container codec at finalize.

video_child: Child

The live gst-launch-1.0 child (stdin → intermediate).

video_stdin: Option<ChildStdin>

Write end of the child’s stdin; None once finalize closes it.

stderr_drain: Option<JoinHandle<String>>

Drains the child’s stderr on a side thread so a chatty pipeline can’t deadlock on a full stderr pipe; joined at finalize for diagnostics.

audio_writer: BufWriter<File>

expected_video_bytes_per_frame: usize

frames_pushed: u64

audio_chunks_pushed: u64

Implementations

impl LiveGstreamerEncoder

pub fn new(config: EncoderConfig) -> Result<Self, EncodeError>

Spawn the live video-encode pipeline + open the audio scratch.

Errors

• EncodeError::InvalidConfig — any of width / height / framerate / channels / sample_rate is zero.
• EncodeError::Unsupported — no encoder wired for (format, OS).
• EncodeError::Spawn — gst-launch-1.0 missing from PATH.
• EncodeError::Io — the audio scratch can’t be created.

pub fn frames_pushed(&self) -> u64

Frame count pushed so far.

pub fn audio_chunks_pushed(&self) -> u64

Audio chunks pushed so far.

pub fn config(&self) -> &EncoderConfig

Borrow the resolved encoder config.

Trait Implementations

impl Debug for LiveGstreamerEncoder

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Drop for LiveGstreamerEncoder

fn drop(&mut self)

Executes the destructor for this type.

fn pin_drop(self: Pin<&mut Self>)

🔬This is a nightly-only experimental API. (pin_ergonomics)

Execute the destructor for this type, but different to Drop::drop, it requires self to be pinned.

impl VideoEncoder for LiveGstreamerEncoder

fn push_video_frame( &mut self, bgra: &[u8], _pts: Duration, ) -> Result<(), EncodeError>

Push one BGRA frame at the given monotonic PTS (measured from session start). bgra.len() must equal width * height * 4.

fn push_audio_chunk( &mut self, samples: &[f32], _pts: Duration, ) -> Result<(), EncodeError>

Push interleaved F32LE audio samples at the given PTS. Sample layout is [ch0, ch1, ch0, ch1, ...] for stereo.

fn finalize(self: Box<Self>) -> Result<PathBuf, EncodeError>

Finalize: spawn the gst-launch pipeline that consumes the scratch files and writes the final container at the configured output path. Consumes self because the encoder is single-use.