whatsapp-rust 0.7.0

//! Video endpoints for WhatsApp calls. The library transports pre-encoded H.264 — it never touches
//! pixels — so a source hands us complete Annex-B access units (start codes included) and a sink
//! receives reassembled peer AUs. The codec lives with the consumer (ffmpeg, WebCodecs, a hardware
//! encoder). WhatsApp uses H.264 Constrained Baseline (avc1.42E01F), repeated SPS/PPS, and adapts
//! from a low-bandwidth 15 fps mode up to 1280x720 @ 20 fps / ~2 Mbps. A bare channel keeps the
//! compatibility cadence of 15 fps; custom sources report their RTP stride explicitly.

pub use wacore::voip::VideoFrame;

/// A video source for a call: one complete H.264 Annex-B access unit per item. Channel-factory
/// shaped for the same reasons as [`AudioSource`](crate::voip::audio::AudioSource); a closed
/// channel (encoder gone) does NOT end the call — audio keeps running.
pub trait VideoSource: Send + Sync + 'static {
    /// The channel the facade reads encoded AUs from. Called once when video starts.
    fn frames(&self) -> async_channel::Receiver<Vec<u8>>;

    /// RTP clock increment between access units. It must match the source's pacing
    /// (`90_000 / frames_per_second`) and remain non-zero.
    fn rtp_timestamp_stride(&self) -> u32 {
        wacore::voip::rtp::VIDEO_TS_STRIDE_15FPS
    }
}

/// A video sink for a call: reassembled peer access units, with keyframe/orientation metadata.
/// VoIP is loss tolerant, so the facade drops a frame if the sink can't keep up.
pub trait VideoSink: Send + Sync + 'static {
    /// The channel the facade writes received AUs to. Called once when video starts.
    fn playout(&self) -> async_channel::Sender<VideoFrame>;
}

/// Blanket impls so a bare `async_channel` endpoint is usable directly, like the audio ones.
impl VideoSource for async_channel::Receiver<Vec<u8>> {
    fn frames(&self) -> async_channel::Receiver<Vec<u8>> {
        self.clone()
    }
}

impl VideoSink for async_channel::Sender<VideoFrame> {
    fn playout(&self) -> async_channel::Sender<VideoFrame> {
        self.clone()
    }
}