Function decode_loop

src/media/video_player.rs:156–279

(
    path: &str,
    cancel: Arc<AtomicBool>,
    finished: Arc<AtomicBool>,
    latest_frame: Arc<Mutex<Option<FrameBuffer>>>,
)

}

fn decode_loop(
    path: &str,
    cancel: Arc<AtomicBool>,
    finished: Arc<AtomicBool>,
    latest_frame: Arc<Mutex<Option<FrameBuffer>>>,
) -> Result<(), MediaError> {
    let mut ictx = input(path).map_err(|e| MediaError::DecodeVideo {
        path: path.to_string(),
        reason: format!("open input: {e}"),
    })?;

    // 视频流
    let video_stream =
        ictx.streams()
            .best(MediaType::Video)
            .ok_or_else(|| MediaError::DecodeVideo {
                path: path.to_string(),
                reason: "no video stream".into(),
            })?;
    let video_stream_index = video_stream.index();
    let video_time_base: Rational = video_stream.time_base();

    let video_ctx = ffmpeg::codec::context::Context::from_parameters(video_stream.parameters())
        .map_err(|e| MediaError::DecodeVideo {
            path: path.to_string(),
            reason: format!("video codec ctx: {e}"),
        })?;
    let mut video_decoder = video_ctx
        .decoder()
        .video()
        .map_err(|e| MediaError::DecodeVideo {
            path: path.to_string(),
            reason: format!("video decoder: {e}"),
        })?;
    let src_w = video_decoder.width();
    let src_h = video_decoder.height();
    let mut scaler = ScalingContext::get(
        video_decoder.format(),
        src_w,
        src_h,
        Pixel::RGBA,
        src_w,
        src_h,
        Flags::BILINEAR,
    )
    .map_err(|e| MediaError::DecodeVideo {
        path: path.to_string(),
        reason: format!("sws context: {e}"),
    })?;

    // 音频流
    let audio_setup = setup_audio(&ictx).map_err(|mut e| {
        if let MediaError::DecodeVideo {
            path: ref mut p, ..
        } = e
        {
            if p.is_empty() {
                *p = path.to_string();