Enum PixelFormat

rustcv-camera/src/pixel_format.rs:22–73

/// - `Other(u32)` 保留了对未知格式的扩展性
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum PixelFormat {
    /// Motion JPEG compressed format.
    /// Most common compressed format for USB cameras.
    /// Low bandwidth, requires CPU decoding.
    ///
    /// Motion JPEG 压缩格式。
    /// USB 摄像头最常见的压缩格式。带宽低，需要 CPU 解码。
    Mjpeg,

    /// YUYV 4:2:2 uncompressed format.
    /// Most common uncompressed format for USB cameras.
    /// 2 bytes per pixel, simple CPU conversion to BGR.
    ///
    /// YUYV 4:2:2 无压缩格式。
    /// USB 摄像头最常见的无压缩格式。每像素 2 字节，CPU 转换为 BGR 简单。
    Yuyv,

    /// NV12 (YUV 4:2:0 semi-planar) format.
    /// Common on mobile/embedded devices.
    /// 1.5 bytes per pixel.
    ///
    /// NV12（YUV 4:2:0 半平面）格式。
    /// 常见于手机/嵌入式设备。每像素 1.5 字节。
    Nv12,

    /// BGR 24-bit format (Blue-Green-Red).
    /// OpenCV's default channel order. Already decoded, no conversion needed.
    ///
    /// BGR 24 位格式（蓝-绿-红）。
    /// OpenCV 默认的通道顺序。已解码，无需转换。
    Bgr24,

    /// RGB 24-bit format (Red-Green-Blue).
    /// Standard display order. Needs channel swap for OpenCV compatibility.
    ///
    /// RGB 24 位格式（红-绿-蓝）。
    /// 标准显示顺序。需要通道交换以兼容 OpenCV。
    Rgb24,

    /// BGRA 32-bit format (Blue-Green-Red-Alpha, 4 bytes per pixel).
    /// Native output from macOS AVFoundation (kCVPixelFormatType_32BGRA).
    /// The Alpha channel is ignored during decode; only BGR is used.
    ///
    /// BGRA 32 位格式（蓝-绿-红-透明度，每像素 4 字节）。
    /// macOS AVFoundation 的原生输出格式（kCVPixelFormatType_32BGRA）。
    /// 解码时忽略 Alpha 通道，仅使用 BGR。
    Bgra32,

    /// Unknown or unsupported format, stored as raw FourCC value.
    /// 未知或不支持的格式，存储为原始 FourCC 值。
    Other(u32),
}

/// Helper macro to build a FourCC u32 from 4 ASCII bytes.
/// 辅助宏：从 4 个 ASCII 字节构造 FourCC u32 值。