Function libwebp::WebPEncodeRGB

pub fn WebPEncodeRGB(
    rgb: &[u8],
    width: u32,
    height: u32,
    stride: u32,
    quality_factor: f32
) -> Result<WebpBox<[u8]>, WebPSimpleError>

Same as WebPEncodeRGBA, but expecting R, G, B, R, G, B… ordered data.