zenwebp 0.4.4

//! Info related to the vp8 codec that can be used in both
//! the decoder and the encoder
//!
//! Mostly common constants and types

// Allow dead code when std is disabled - some types are encoder-only
#![cfg_attr(not(feature = "std"), allow(dead_code))]

use alloc::vec::Vec;

/// A decoded or encoded VP8 frame containing YUV data.
#[derive(Clone, Default)]
pub struct Frame {
    /// The width of the luma plane
    pub width: u16,

    /// The height of the luma plane
    pub height: u16,

    /// The luma plane of the frame
    pub ybuf: Vec<u8>,

    /// The blue plane of the frame
    pub ubuf: Vec<u8>,

    /// The red plane of the frame
    pub vbuf: Vec<u8>,

    pub(crate) version: u8,

    /// Indicates whether this frame is intended for display
    pub for_display: bool,

    // Section 9.2
    /// The pixel type of the frame as defined by Section 9.2
    /// of the VP8 Specification
    #[allow(dead_code)] // Part of public API, may be read by users
    pub pixel_type: u8,

    // Section 9.4 and 15
    pub(crate) filter_type: bool, //if true uses simple filter // if false uses normal filter
    pub(crate) filter_level: u8,
    pub(crate) sharpness_level: u8,
}

/// Different planes to be encoded/decoded in DCT coefficient decoding
/// in 13.3 of the spec
#[derive(Clone, Copy, PartialEq)]
pub(crate) enum Plane {
    /// The Y plane after decoding Y2
    YCoeff1 = 0,
    /// The Y2 plane (specifies the 0th coefficient of the other Y blocks)
    Y2 = 1,
    /// The U or V plane
    Chroma = 2,
    /// The Y plane when there is no Y2 plane
    YCoeff0 = 3,
}

pub(crate) const MAX_SEGMENTS: usize = 4;
pub(crate) const NUM_DCT_TOKENS: usize = 12;

// Prediction modes
pub(crate) const DC_PRED: i8 = 0;
pub(crate) const V_PRED: i8 = 1;
pub(crate) const H_PRED: i8 = 2;
pub(crate) const TM_PRED: i8 = 3;
pub(crate) const B_PRED: i8 = 4;

pub(crate) const B_DC_PRED: i8 = 0;
pub(crate) const B_TM_PRED: i8 = 1;
pub(crate) const B_VE_PRED: i8 = 2;
pub(crate) const B_HE_PRED: i8 = 3;
pub(crate) const B_LD_PRED: i8 = 4;
pub(crate) const B_RD_PRED: i8 = 5;
pub(crate) const B_VR_PRED: i8 = 6;
pub(crate) const B_VL_PRED: i8 = 7;
pub(crate) const B_HD_PRED: i8 = 8;
pub(crate) const B_HU_PRED: i8 = 9;

/// VP8 luma (Y) macroblock prediction mode.
#[doc(hidden)]
#[repr(i8)]
#[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
pub enum LumaMode {
    /// Predict DC using row above and column to the left.
    #[default]
    DC = DC_PRED,

    /// Predict rows using row above.
    V = V_PRED,

    /// Predict columns using column to the left.
    H = H_PRED,

    /// Propagate second differences.
    TM = TM_PRED,

    /// Each Y subblock is independently predicted.
    B = B_PRED,
}

impl LumaMode {
    #[allow(dead_code)]
    pub(crate) const fn from_i8(val: i8) -> Option<Self> {
        Some(match val {
            DC_PRED => Self::DC,
            V_PRED => Self::V,
            H_PRED => Self::H,
            TM_PRED => Self::TM,
            B_PRED => Self::B,
            _ => return None,
        })
    }

    pub(crate) const fn into_intra(self) -> Option<IntraMode> {
        Some(match self {
            Self::DC => IntraMode::DC,
            Self::V => IntraMode::VE,
            Self::H => IntraMode::HE,
            Self::TM => IntraMode::TM,
            Self::B => return None,
        })
    }
}

/// VP8 chroma (U/V) macroblock prediction mode.
#[doc(hidden)]
#[repr(i8)]
#[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
pub enum ChromaMode {
    /// Predict DC using row above and column to the left.
    #[default]
    DC = DC_PRED,

    /// Predict rows using row above.
    V = V_PRED,

    /// Predict columns using column to the left.
    H = H_PRED,

    /// Propagate second differences.
    TM = TM_PRED,
}

impl ChromaMode {
    #[allow(dead_code)]
    pub(crate) const fn from_i8(val: i8) -> Option<Self> {
        Some(match val {
            DC_PRED => Self::DC,
            V_PRED => Self::V,
            H_PRED => Self::H,
            TM_PRED => Self::TM,
            _ => return None,
        })
    }
}

/// VP8 intra prediction mode for 4x4 sub-blocks (B_PRED mode).
#[doc(hidden)]
#[repr(i8)]
#[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
pub enum IntraMode {
    /// DC prediction - average of neighbors.
    #[default]
    DC = B_DC_PRED,
    /// True motion - propagate second differences.
    TM = B_TM_PRED,
    /// Vertical edge prediction.
    VE = B_VE_PRED,
    /// Horizontal edge prediction.
    HE = B_HE_PRED,
    /// Left-down diagonal prediction.
    LD = B_LD_PRED,
    /// Right-down diagonal prediction.
    RD = B_RD_PRED,
    /// Vertical-right diagonal prediction.
    VR = B_VR_PRED,
    /// Vertical-left diagonal prediction.
    VL = B_VL_PRED,
    /// Horizontal-down diagonal prediction.
    HD = B_HD_PRED,
    /// Horizontal-up diagonal prediction.
    HU = B_HU_PRED,
}

impl IntraMode {
    #[allow(dead_code)]
    pub(crate) const fn from_i8(val: i8) -> Option<Self> {
        Some(match val {
            B_DC_PRED => Self::DC,
            B_TM_PRED => Self::TM,
            B_VE_PRED => Self::VE,
            B_HE_PRED => Self::HE,
            B_LD_PRED => Self::LD,
            B_RD_PRED => Self::RD,
            B_VR_PRED => Self::VR,
            B_VL_PRED => Self::VL,
            B_HD_PRED => Self::HD,
            B_HU_PRED => Self::HU,
            _ => return None,
        })
    }
}

/// The probability used in the arithmetic coder is a u8 for each byte
pub(crate) type Prob = u8;

pub(crate) const SEGMENT_ID_TREE: [i8; 6] = [2, 4, -0, -1, -2, -3];

// Section 11.2
// Tree for determining the keyframe luma intra prediction modes:
pub(crate) const KEYFRAME_YMODE_TREE: [i8; 8] =
    [-B_PRED, 2, 4, 6, -DC_PRED, -V_PRED, -H_PRED, -TM_PRED];

// Default probabilities for decoding the keyframe luma modes
pub(crate) const KEYFRAME_YMODE_PROBS: [Prob; 4] = [145, 156, 163, 128];

// Tree for determining the keyframe B_PRED mode:
pub(crate) const KEYFRAME_BPRED_MODE_TREE: [i8; 18] = [
    -B_DC_PRED, 2, -B_TM_PRED, 4, -B_VE_PRED, 6, 8, 12, -B_HE_PRED, 10, -B_RD_PRED, -B_VR_PRED,
    -B_LD_PRED, 14, -B_VL_PRED, 16, -B_HD_PRED, -B_HU_PRED,
];

// Probabilities for the BPRED_MODE_TREE
pub(crate) const KEYFRAME_BPRED_MODE_PROBS: [[[Prob; 9]; 10]; 10] = [
    [
        [231, 120, 48, 89, 115, 113, 120, 152, 112],
        [152, 179, 64, 126, 170, 118, 46, 70, 95],
        [175, 69, 143, 80, 85, 82, 72, 155, 103],
        [56, 58, 10, 171, 218, 189, 17, 13, 152],
        [144, 71, 10, 38, 171, 213, 144, 34, 26],
        [114, 26, 17, 163, 44, 195, 21, 10, 173],
        [121, 24, 80, 195, 26, 62, 44, 64, 85],
        [170, 46, 55, 19, 136, 160, 33, 206, 71],
        [63, 20, 8, 114, 114, 208, 12, 9, 226],
        [81, 40, 11, 96, 182, 84, 29, 16, 36],
    ],
    [
        [134, 183, 89, 137, 98, 101, 106, 165, 148],
        [72, 187, 100, 130, 157, 111, 32, 75, 80],
        [66, 102, 167, 99, 74, 62, 40, 234, 128],
        [41, 53, 9, 178, 241, 141, 26, 8, 107],
        [104, 79, 12, 27, 217, 255, 87, 17, 7],
        [74, 43, 26, 146, 73, 166, 49, 23, 157],
        [65, 38, 105, 160, 51, 52, 31, 115, 128],
        [87, 68, 71, 44, 114, 51, 15, 186, 23],
        [47, 41, 14, 110, 182, 183, 21, 17, 194],
        [66, 45, 25, 102, 197, 189, 23, 18, 22],
    ],
    [
        [88, 88, 147, 150, 42, 46, 45, 196, 205],
        [43, 97, 183, 117, 85, 38, 35, 179, 61],
        [39, 53, 200, 87, 26, 21, 43, 232, 171],
        [56, 34, 51, 104, 114, 102, 29, 93, 77],
        [107, 54, 32, 26, 51, 1, 81, 43, 31],
        [39, 28, 85, 171, 58, 165, 90, 98, 64],
        [34, 22, 116, 206, 23, 34, 43, 166, 73],
        [68, 25, 106, 22, 64, 171, 36, 225, 114],
        [34, 19, 21, 102, 132, 188, 16, 76, 124],
        [62, 18, 78, 95, 85, 57, 50, 48, 51],
    ],
    [
        [193, 101, 35, 159, 215, 111, 89, 46, 111],
        [60, 148, 31, 172, 219, 228, 21, 18, 111],
        [112, 113, 77, 85, 179, 255, 38, 120, 114],
        [40, 42, 1, 196, 245, 209, 10, 25, 109],
        [100, 80, 8, 43, 154, 1, 51, 26, 71],
        [88, 43, 29, 140, 166, 213, 37, 43, 154],
        [61, 63, 30, 155, 67, 45, 68, 1, 209],
        [142, 78, 78, 16, 255, 128, 34, 197, 171],
        [41, 40, 5, 102, 211, 183, 4, 1, 221],
        [51, 50, 17, 168, 209, 192, 23, 25, 82],
    ],
    [
        [125, 98, 42, 88, 104, 85, 117, 175, 82],
        [95, 84, 53, 89, 128, 100, 113, 101, 45],
        [75, 79, 123, 47, 51, 128, 81, 171, 1],
        [57, 17, 5, 71, 102, 57, 53, 41, 49],
        [115, 21, 2, 10, 102, 255, 166, 23, 6],
        [38, 33, 13, 121, 57, 73, 26, 1, 85],
        [41, 10, 67, 138, 77, 110, 90, 47, 114],
        [101, 29, 16, 10, 85, 128, 101, 196, 26],
        [57, 18, 10, 102, 102, 213, 34, 20, 43],
        [117, 20, 15, 36, 163, 128, 68, 1, 26],
    ],
    [
        [138, 31, 36, 171, 27, 166, 38, 44, 229],
        [67, 87, 58, 169, 82, 115, 26, 59, 179],
        [63, 59, 90, 180, 59, 166, 93, 73, 154],
        [40, 40, 21, 116, 143, 209, 34, 39, 175],
        [57, 46, 22, 24, 128, 1, 54, 17, 37],
        [47, 15, 16, 183, 34, 223, 49, 45, 183],
        [46, 17, 33, 183, 6, 98, 15, 32, 183],
        [65, 32, 73, 115, 28, 128, 23, 128, 205],
        [40, 3, 9, 115, 51, 192, 18, 6, 223],
        [87, 37, 9, 115, 59, 77, 64, 21, 47],
    ],
    [
        [104, 55, 44, 218, 9, 54, 53, 130, 226],
        [64, 90, 70, 205, 40, 41, 23, 26, 57],
        [54, 57, 112, 184, 5, 41, 38, 166, 213],
        [30, 34, 26, 133, 152, 116, 10, 32, 134],
        [75, 32, 12, 51, 192, 255, 160, 43, 51],
        [39, 19, 53, 221, 26, 114, 32, 73, 255],
        [31, 9, 65, 234, 2, 15, 1, 118, 73],
        [88, 31, 35, 67, 102, 85, 55, 186, 85],
        [56, 21, 23, 111, 59, 205, 45, 37, 192],
        [55, 38, 70, 124, 73, 102, 1, 34, 98],
    ],
    [
        [102, 61, 71, 37, 34, 53, 31, 243, 192],
        [69, 60, 71, 38, 73, 119, 28, 222, 37],
        [68, 45, 128, 34, 1, 47, 11, 245, 171],
        [62, 17, 19, 70, 146, 85, 55, 62, 70],
        [75, 15, 9, 9, 64, 255, 184, 119, 16],
        [37, 43, 37, 154, 100, 163, 85, 160, 1],
        [63, 9, 92, 136, 28, 64, 32, 201, 85],
        [86, 6, 28, 5, 64, 255, 25, 248, 1],
        [56, 8, 17, 132, 137, 255, 55, 116, 128],
        [58, 15, 20, 82, 135, 57, 26, 121, 40],
    ],
    [
        [164, 50, 31, 137, 154, 133, 25, 35, 218],
        [51, 103, 44, 131, 131, 123, 31, 6, 158],
        [86, 40, 64, 135, 148, 224, 45, 183, 128],
        [22, 26, 17, 131, 240, 154, 14, 1, 209],
        [83, 12, 13, 54, 192, 255, 68, 47, 28],
        [45, 16, 21, 91, 64, 222, 7, 1, 197],
        [56, 21, 39, 155, 60, 138, 23, 102, 213],
        [85, 26, 85, 85, 128, 128, 32, 146, 171],
        [18, 11, 7, 63, 144, 171, 4, 4, 246],
        [35, 27, 10, 146, 174, 171, 12, 26, 128],
    ],
    [
        [190, 80, 35, 99, 180, 80, 126, 54, 45],
        [85, 126, 47, 87, 176, 51, 41, 20, 32],
        [101, 75, 128, 139, 118, 146, 116, 128, 85],
        [56, 41, 15, 176, 236, 85, 37, 9, 62],
        [146, 36, 19, 30, 171, 255, 97, 27, 20],
        [71, 30, 17, 119, 118, 255, 17, 18, 138],
        [101, 38, 60, 138, 55, 70, 43, 26, 142],
        [138, 45, 61, 62, 219, 1, 81, 188, 64],
        [32, 41, 20, 117, 151, 142, 20, 21, 163],
        [112, 19, 12, 61, 195, 128, 48, 4, 24],
    ],
];

// Section 11.4 Tree for determining macroblock the chroma mode
pub(crate) const KEYFRAME_UV_MODE_TREE: [i8; 6] = [-DC_PRED, 2, -V_PRED, 4, -H_PRED, -TM_PRED];

// Probabilities for determining macroblock mode
pub(crate) const KEYFRAME_UV_MODE_PROBS: [Prob; 3] = [142, 114, 183];

// Section 13.4
pub(crate) type TokenProbTables = [[[[Prob; NUM_DCT_TOKENS - 1]; 3]; 8]; 4];

// Probabilities that a token's probability will be updated
pub(crate) const COEFF_UPDATE_PROBS: TokenProbTables = [
    [
        [
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [176, 246, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [223, 241, 252, 255, 255, 255, 255, 255, 255, 255, 255],
            [249, 253, 253, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 244, 252, 255, 255, 255, 255, 255, 255, 255, 255],
            [234, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [253, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 246, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [239, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [254, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 248, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [251, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [251, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [254, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 254, 253, 255, 254, 255, 255, 255, 255, 255, 255],
            [250, 255, 254, 255, 254, 255, 255, 255, 255, 255, 255],
            [254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
    ],
    [
        [
            [217, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [225, 252, 241, 253, 255, 255, 254, 255, 255, 255, 255],
            [234, 250, 241, 250, 253, 255, 253, 254, 255, 255, 255],
        ],
        [
            [255, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [223, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [238, 253, 254, 254, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 248, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [249, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 253, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [247, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [252, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [253, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 254, 253, 255, 255, 255, 255, 255, 255, 255, 255],
            [250, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
    ],
    [
        [
            [186, 251, 250, 255, 255, 255, 255, 255, 255, 255, 255],
            [234, 251, 244, 254, 255, 255, 255, 255, 255, 255, 255],
            [251, 251, 243, 253, 254, 255, 254, 255, 255, 255, 255],
        ],
        [
            [255, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [236, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [251, 253, 253, 254, 254, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [254, 254, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [254, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
    ],
    [
        [
            [248, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [250, 254, 252, 254, 255, 255, 255, 255, 255, 255, 255],
            [248, 254, 249, 253, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 253, 253, 255, 255, 255, 255, 255, 255, 255, 255],
            [246, 253, 253, 255, 255, 255, 255, 255, 255, 255, 255],
            [252, 254, 251, 254, 254, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 254, 252, 255, 255, 255, 255, 255, 255, 255, 255],
            [248, 254, 253, 255, 255, 255, 255, 255, 255, 255, 255],
            [253, 255, 254, 254, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 251, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [245, 251, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [253, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 251, 253, 255, 255, 255, 255, 255, 255, 255, 255],
            [252, 253, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 254, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 252, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [249, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 254, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 255, 253, 255, 255, 255, 255, 255, 255, 255, 255],
            [250, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
        [
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [254, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
            [255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255],
        ],
    ],
];

// Section 13.5
// Default Probabilities for tokens
pub(crate) const COEFF_PROBS: TokenProbTables = [
    [
        [
            [128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
            [128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
            [128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
        ],
        [
            [253, 136, 254, 255, 228, 219, 128, 128, 128, 128, 128],
            [189, 129, 242, 255, 227, 213, 255, 219, 128, 128, 128],
            [106, 126, 227, 252, 214, 209, 255, 255, 128, 128, 128],
        ],
        [
            [1, 98, 248, 255, 236, 226, 255, 255, 128, 128, 128],
            [181, 133, 238, 254, 221, 234, 255, 154, 128, 128, 128],
            [78, 134, 202, 247, 198, 180, 255, 219, 128, 128, 128],
        ],
        [
            [1, 185, 249, 255, 243, 255, 128, 128, 128, 128, 128],
            [184, 150, 247, 255, 236, 224, 128, 128, 128, 128, 128],
            [77, 110, 216, 255, 236, 230, 128, 128, 128, 128, 128],
        ],
        [
            [1, 101, 251, 255, 241, 255, 128, 128, 128, 128, 128],
            [170, 139, 241, 252, 236, 209, 255, 255, 128, 128, 128],
            [37, 116, 196, 243, 228, 255, 255, 255, 128, 128, 128],
        ],
        [
            [1, 204, 254, 255, 245, 255, 128, 128, 128, 128, 128],
            [207, 160, 250, 255, 238, 128, 128, 128, 128, 128, 128],
            [102, 103, 231, 255, 211, 171, 128, 128, 128, 128, 128],
        ],
        [
            [1, 152, 252, 255, 240, 255, 128, 128, 128, 128, 128],
            [177, 135, 243, 255, 234, 225, 128, 128, 128, 128, 128],
            [80, 129, 211, 255, 194, 224, 128, 128, 128, 128, 128],
        ],
        [
            [1, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128],
            [246, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128],
            [255, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
        ],
    ],
    [
        [
            [198, 35, 237, 223, 193, 187, 162, 160, 145, 155, 62],
            [131, 45, 198, 221, 172, 176, 220, 157, 252, 221, 1],
            [68, 47, 146, 208, 149, 167, 221, 162, 255, 223, 128],
        ],
        [
            [1, 149, 241, 255, 221, 224, 255, 255, 128, 128, 128],
            [184, 141, 234, 253, 222, 220, 255, 199, 128, 128, 128],
            [81, 99, 181, 242, 176, 190, 249, 202, 255, 255, 128],
        ],
        [
            [1, 129, 232, 253, 214, 197, 242, 196, 255, 255, 128],
            [99, 121, 210, 250, 201, 198, 255, 202, 128, 128, 128],
            [23, 91, 163, 242, 170, 187, 247, 210, 255, 255, 128],
        ],
        [
            [1, 200, 246, 255, 234, 255, 128, 128, 128, 128, 128],
            [109, 178, 241, 255, 231, 245, 255, 255, 128, 128, 128],
            [44, 130, 201, 253, 205, 192, 255, 255, 128, 128, 128],
        ],
        [
            [1, 132, 239, 251, 219, 209, 255, 165, 128, 128, 128],
            [94, 136, 225, 251, 218, 190, 255, 255, 128, 128, 128],
            [22, 100, 174, 245, 186, 161, 255, 199, 128, 128, 128],
        ],
        [
            [1, 182, 249, 255, 232, 235, 128, 128, 128, 128, 128],
            [124, 143, 241, 255, 227, 234, 128, 128, 128, 128, 128],
            [35, 77, 181, 251, 193, 211, 255, 205, 128, 128, 128],
        ],
        [
            [1, 157, 247, 255, 236, 231, 255, 255, 128, 128, 128],
            [121, 141, 235, 255, 225, 227, 255, 255, 128, 128, 128],
            [45, 99, 188, 251, 195, 217, 255, 224, 128, 128, 128],
        ],
        [
            [1, 1, 251, 255, 213, 255, 128, 128, 128, 128, 128],
            [203, 1, 248, 255, 255, 128, 128, 128, 128, 128, 128],
            [137, 1, 177, 255, 224, 255, 128, 128, 128, 128, 128],
        ],
    ],
    [
        [
            [253, 9, 248, 251, 207, 208, 255, 192, 128, 128, 128],
            [175, 13, 224, 243, 193, 185, 249, 198, 255, 255, 128],
            [73, 17, 171, 221, 161, 179, 236, 167, 255, 234, 128],
        ],
        [
            [1, 95, 247, 253, 212, 183, 255, 255, 128, 128, 128],
            [239, 90, 244, 250, 211, 209, 255, 255, 128, 128, 128],
            [155, 77, 195, 248, 188, 195, 255, 255, 128, 128, 128],
        ],
        [
            [1, 24, 239, 251, 218, 219, 255, 205, 128, 128, 128],
            [201, 51, 219, 255, 196, 186, 128, 128, 128, 128, 128],
            [69, 46, 190, 239, 201, 218, 255, 228, 128, 128, 128],
        ],
        [
            [1, 191, 251, 255, 255, 128, 128, 128, 128, 128, 128],
            [223, 165, 249, 255, 213, 255, 128, 128, 128, 128, 128],
            [141, 124, 248, 255, 255, 128, 128, 128, 128, 128, 128],
        ],
        [
            [1, 16, 248, 255, 255, 128, 128, 128, 128, 128, 128],
            [190, 36, 230, 255, 236, 255, 128, 128, 128, 128, 128],
            [149, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128],
        ],
        [
            [1, 226, 255, 128, 128, 128, 128, 128, 128, 128, 128],
            [247, 192, 255, 128, 128, 128, 128, 128, 128, 128, 128],
            [240, 128, 255, 128, 128, 128, 128, 128, 128, 128, 128],
        ],
        [
            [1, 134, 252, 255, 255, 128, 128, 128, 128, 128, 128],
            [213, 62, 250, 255, 255, 128, 128, 128, 128, 128, 128],
            [55, 93, 255, 128, 128, 128, 128, 128, 128, 128, 128],
        ],
        [
            [128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
            [128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
            [128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128],
        ],
    ],
    [
        [
            [202, 24, 213, 235, 186, 191, 220, 160, 240, 175, 255],
            [126, 38, 182, 232, 169, 184, 228, 174, 255, 187, 128],
            [61, 46, 138, 219, 151, 178, 240, 170, 255, 216, 128],
        ],
        [
            [1, 112, 230, 250, 199, 191, 247, 159, 255, 255, 128],
            [166, 109, 228, 252, 211, 215, 255, 174, 128, 128, 128],
            [39, 77, 162, 232, 172, 180, 245, 178, 255, 255, 128],
        ],
        [
            [1, 52, 220, 246, 198, 199, 249, 220, 255, 255, 128],
            [124, 74, 191, 243, 183, 193, 250, 221, 255, 255, 128],
            [24, 71, 130, 219, 154, 170, 243, 182, 255, 255, 128],
        ],
        [
            [1, 182, 225, 249, 219, 240, 255, 224, 128, 128, 128],
            [149, 150, 226, 252, 216, 205, 255, 171, 128, 128, 128],
            [28, 108, 170, 242, 183, 194, 254, 223, 255, 255, 128],
        ],
        [
            [1, 81, 230, 252, 204, 203, 255, 192, 128, 128, 128],
            [123, 102, 209, 247, 188, 196, 255, 233, 128, 128, 128],
            [20, 95, 153, 243, 164, 173, 255, 203, 128, 128, 128],
        ],
        [
            [1, 222, 248, 255, 216, 213, 128, 128, 128, 128, 128],
            [168, 175, 246, 252, 235, 205, 255, 255, 128, 128, 128],
            [47, 116, 215, 255, 211, 212, 255, 255, 128, 128, 128],
        ],
        [
            [1, 121, 236, 253, 212, 214, 255, 255, 128, 128, 128],
            [141, 84, 213, 252, 201, 202, 255, 219, 128, 128, 128],
            [42, 80, 160, 240, 162, 185, 255, 205, 128, 128, 128],
        ],
        [
            [1, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128],
            [244, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128],
            [238, 1, 255, 128, 128, 128, 128, 128, 128, 128, 128],
        ],
    ],
];

// DCT Tokens
pub(crate) const DCT_0: i8 = 0;
pub(crate) const DCT_1: i8 = 1;
pub(crate) const DCT_2: i8 = 2;
pub(crate) const DCT_3: i8 = 3;
pub(crate) const DCT_4: i8 = 4;
pub(crate) const DCT_CAT1: i8 = 5;
pub(crate) const DCT_CAT2: i8 = 6;
pub(crate) const DCT_CAT3: i8 = 7;
pub(crate) const DCT_CAT4: i8 = 8;
pub(crate) const DCT_CAT5: i8 = 9;
pub(crate) const DCT_CAT6: i8 = 10;
pub(crate) const DCT_EOB: i8 = 11;

pub(crate) const DCT_TOKEN_TREE: [i8; 22] = [
    -DCT_EOB, 2, -DCT_0, 4, -DCT_1, 6, 8, 12, -DCT_2, 10, -DCT_3, -DCT_4, 14, 16, -DCT_CAT1,
    -DCT_CAT2, 18, 20, -DCT_CAT3, -DCT_CAT4, -DCT_CAT5, -DCT_CAT6,
];

pub(crate) const PROB_DCT_CAT: [[Prob; 12]; 6] = [
    [159, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
    [165, 145, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
    [173, 148, 140, 0, 0, 0, 0, 0, 0, 0, 0, 0],
    [176, 155, 140, 135, 0, 0, 0, 0, 0, 0, 0, 0],
    [180, 157, 141, 134, 130, 0, 0, 0, 0, 0, 0, 0],
    [254, 254, 243, 230, 196, 177, 153, 140, 133, 130, 129, 0],
];

pub(crate) const DCT_CAT_BASE: [u8; 6] = [5, 7, 11, 19, 35, 67];
pub(crate) const COEFF_BANDS: [u8; 16] = [0, 1, 2, 3, 6, 4, 5, 6, 6, 6, 6, 6, 6, 6, 6, 7];

#[rustfmt::skip]
pub(crate) const DC_QUANT: [i16; 128] = [
      4,   5,   6,   7,   8,   9,  10,  10,
     11,  12,  13,  14,  15,  16,  17,  17,
     18,  19,  20,  20,  21,  21,  22,  22,
     23,  23,  24,  25,  25,  26,  27,  28,
     29,  30,  31,  32,  33,  34,  35,  36,
     37,  37,  38,  39,  40,  41,  42,  43,
     44,  45,  46,  46,  47,  48,  49,  50,
     51,  52,  53,  54,  55,  56,  57,  58,
     59,  60,  61,  62,  63,  64,  65,  66,
     67,  68,  69,  70,  71,  72,  73,  74,
     75,  76,  76,  77,  78,  79,  80,  81,
     82,  83,  84,  85,  86,  87,  88,  89,
     91,  93,  95,  96,  98, 100, 101, 102,
    104, 106, 108, 110, 112, 114, 116, 118,
    122, 124, 126, 128, 130, 132, 134, 136,
    138, 140, 143, 145, 148, 151, 154, 157,
];

#[rustfmt::skip]
pub(crate) const AC_QUANT: [i16; 128] = [
      4,   5,   6,   7,   8,    9,  10,  11,
      12,  13,  14,  15,  16,  17,  18,  19,
      20,  21,  22,  23,  24,  25,  26,  27,
      28,  29,  30,  31,  32,  33,  34,  35,
      36,  37,  38,  39,  40,  41,  42,  43,
      44,  45,  46,  47,  48,  49,  50,  51,
      52,  53,  54,  55,  56,  57,  58,  60,
      62,  64,  66,  68,  70,  72,  74,  76,
      78,  80,  82,  84,  86,  88,  90,  92,
      94,  96,  98, 100, 102, 104, 106, 108,
     110, 112, 114, 116, 119, 122, 125, 128,
     131, 134, 137, 140, 143, 146, 149, 152,
     155, 158, 161, 164, 167, 170, 173, 177,
     181, 185, 189, 193, 197, 201, 205, 209,
     213, 217, 221, 225, 229, 234, 239, 245,
     249, 254, 259, 264, 269, 274, 279, 284,
];

pub(crate) const ZIGZAG: [u8; 16] = [0, 1, 4, 8, 5, 2, 3, 6, 9, 12, 13, 10, 7, 11, 14, 15];

use crate::encoder::cost::{MatrixType, VP8Matrix};
use crate::encoder::psy::PsyConfig;

#[derive(Clone, Default)]
pub(crate) struct Segment {
    pub(crate) ydc: i16,
    pub(crate) yac: i16,

    pub(crate) y2dc: i16,
    pub(crate) y2ac: i16,

    pub(crate) uvdc: i16,
    pub(crate) uvac: i16,

    #[allow(dead_code)]
    pub(crate) delta_values: bool,

    pub(crate) quantizer_level: i8,
    pub(crate) loopfilter_level: i8,

    // Encoder-specific fields
    /// The quantization index (0-127) for this segment
    #[allow(dead_code)] // Stored for debugging/info purposes
    pub(crate) quant_index: u8,

    // Quantization matrices for trellis optimization
    pub(crate) y1_matrix: Option<VP8Matrix>,
    pub(crate) y2_matrix: Option<VP8Matrix>,
    pub(crate) uv_matrix: Option<VP8Matrix>,

    // Lambda values for trellis quantization (scaled by 256 for fixed-point)
    // Computed as: lambda = (scale * q^2) where q is the AC quantizer
    pub(crate) lambda_trellis_i4: u32,
    pub(crate) lambda_trellis_i16: u32,
    pub(crate) lambda_trellis_uv: u32,

    // Lambda values for RD mode selection
    // These control rate-distortion trade-off in mode decisions
    pub(crate) lambda_i16: u32,
    pub(crate) lambda_i4: u32,
    pub(crate) lambda_uv: u32,
    pub(crate) lambda_mode: u32,

    // Spectral distortion weight (tlambda)
    // Controls how much TDisto affects mode selection
    pub(crate) tlambda: u32,

    // Perceptual encoding config (CSF tables, psy-rd/trellis strengths)
    pub(crate) psy_config: PsyConfig,
}

impl Segment {
    /// Initialize quantization matrices and trellis lambdas from the quantizer values.
    /// `sns_strength` controls spectral distortion weight (0-100, from preset).
    /// `method` is the encoding method level (0-6) used to gate perceptual features.
    pub(crate) fn init_matrices(&mut self, sns_strength: u8, method: u8) {
        self.y1_matrix = Some(VP8Matrix::new(
            self.ydc as u16,
            self.yac as u16,
            MatrixType::Y1,
        ));
        self.y2_matrix = Some(VP8Matrix::new(
            self.y2dc as u16,
            self.y2ac as u16,
            MatrixType::Y2,
        ));
        self.uv_matrix = Some(VP8Matrix::new(
            self.uvdc as u16,
            self.uvac as u16,
            MatrixType::UV,
        ));

        // Compute trellis lambda values based on quantizer
        // These formulas match libwebp's SetupMatrices:
        // lambda_trellis_i4 = (7 * q^2) >> 3
        // lambda_trellis_i16 = q^2 >> 2
        // lambda_trellis_uv = q^2 << 1
        //
        // q values come from ExpandMatrix which returns the average of the
        // 16-element quantization matrix: (q_dc + 15*q_ac + 8) >> 4
        let q_i4 = (self.ydc as u32 + 15 * self.yac as u32 + 8) >> 4;
        let q_i16 = (self.y2dc as u32 + 15 * self.y2ac as u32 + 8) >> 4;
        let q_uv = (self.uvdc as u32 + 15 * self.uvac as u32 + 8) >> 4;

        self.lambda_trellis_i4 = ((7 * q_i4 * q_i4) >> 3).max(1);
        self.lambda_trellis_i16 = ((q_i16 * q_i16) >> 2).max(1);
        self.lambda_trellis_uv = ((q_uv * q_uv) << 1).max(1);

        // Compute RD mode selection lambda values (from libwebp SetSegmentProbas)
        // lambda_i4 = (3 * q^2) >> 7
        // lambda_i16 = 3 * q^2
        // lambda_uv = (3 * q^2) >> 6
        // lambda_mode = (1 * q^2) >> 7
        self.lambda_i4 = ((3 * q_i4 * q_i4) >> 7).max(1);
        self.lambda_i16 = (3 * q_i16 * q_i16).max(1);
        self.lambda_uv = ((3 * q_uv * q_uv) >> 6).max(1);
        self.lambda_mode = ((q_i4 * q_i4) >> 7).max(1);

        // Compute tlambda for spectral distortion weight
        // tlambda = (sns_strength * q) >> 5
        // This enables TDisto in mode selection
        self.tlambda = (u32::from(sns_strength) * q_i4) >> 5;

        // Initialize perceptual config
        self.psy_config = PsyConfig::new(method, self.quant_index, sns_strength);
    }
}