image_rs_plugin.rs

use aviutl2::{anyhow, input::*, utils::flip_vertical};

struct MyPngInputPlugin;

impl InputPlugin for MyPngInputPlugin {
    type InputHandle = image::RgbaImage;

    fn new() -> Self {
        MyPngInputPlugin
    }

    fn plugin_info(&self) -> InputPluginTable {
        InputPluginTable {
            name: "My PNG Input Plugin".to_string(),
            information: "A simple PNG input plugin".to_string(),

            input_type: InputType::Video,
            concurrent: false,
            file_filters: vec![FileFilter {
                name: "PNG Files".to_string(),
                extensions: vec!["png".to_string()],
            }],
            can_config: false,
        }
    }

    fn open(&self, file: std::path::PathBuf) -> AnyResult<Self::InputHandle> {
        let img = image::open(file)?.to_rgba8();
        Ok(img)
    }

    fn close(&self, handle: Self::InputHandle) -> AnyResult<()> {
        drop(handle);
        Ok(())
    }

    fn get_input_info(
        &self,
        handle: &mut Self::InputHandle,
        _video_track: u32,
        _audio_track: u32,
    ) -> AnyResult<InputInfo> {
        let (width, height) = handle.dimensions();

        Ok(InputInfo {
            video: Some(VideoInputInfo {
                fps: Rational32::new(30, 1),
                num_frames: 1,
                manual_frame_index: false,
                width,
                height,
                format: InputPixelFormat::Bgra,
            }),
            audio: None,
        })
    }

    fn read_video(
        &self,
        handle: &Self::InputHandle,
        frame: u32,
        returner: &mut ImageReturner,
    ) -> AnyResult<()> {
        anyhow::ensure!(frame == 0, "Only one frame available");

        let (width, height) = handle.dimensions();
        let mut pixels = handle
            .pixels()
            .map(|p| (p[2], p[1], p[0], p[3]))
            .collect::<Vec<_>>();

        flip_vertical(&mut pixels, width as usize, height as usize);

        returner.write(&pixels);
        Ok(())
    }
}

aviutl2::register_input_plugin!(MyPngInputPlugin);