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// Copyright (c) the JPEG XL Project Authors. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
pub const MAX_COEFF_BLOCKS: usize = 32;
pub const MAX_BLOCK_DIM: usize = 8 * MAX_COEFF_BLOCKS;
pub const MAX_COEFF_AREA: usize = MAX_BLOCK_DIM * MAX_BLOCK_DIM;
#[allow(clippy::upper_case_acronyms)]
#[derive(Copy, Clone, Debug, PartialEq)]
pub enum HfTransformType {
// Update HfTransformType::VALUES when changing this!
// Regular block size DCT
DCT = 0,
// Encode pixels without transforming
// a.k.a "Hornuss"
IDENTITY = 1,
// Use 2-by-2 DCT
DCT2X2 = 2,
// Use 4-by-4 DCT
DCT4X4 = 3,
// Use 16-by-16 DCT
DCT16X16 = 4,
// Use 32-by-32 DCT
DCT32X32 = 5,
// Use 16-by-8 DCT
DCT16X8 = 6,
// Use 8-by-16 DCT
DCT8X16 = 7,
// Use 32-by-8 DCT
DCT32X8 = 8,
// Use 8-by-32 DCT
DCT8X32 = 9,
// Use 32-by-16 DCT
DCT32X16 = 10,
// Use 16-by-32 DCT
DCT16X32 = 11,
// 4x8 and 8x4 DCT
DCT4X8 = 12,
DCT8X4 = 13,
// Corner-DCT.
AFV0 = 14,
AFV1 = 15,
AFV2 = 16,
AFV3 = 17,
// Larger DCTs
DCT64X64 = 18,
DCT64X32 = 19,
DCT32X64 = 20,
// No transforms smaller than 64x64 are allowed below.
DCT128X128 = 21,
DCT128X64 = 22,
DCT64X128 = 23,
DCT256X256 = 24,
DCT256X128 = 25,
DCT128X256 = 26,
}
impl HfTransformType {
pub const INVALID_TRANSFORM: u8 = Self::CARDINALITY as u8;
pub const CARDINALITY: usize = Self::VALUES.len();
pub const VALUES: [HfTransformType; 27] = [
HfTransformType::DCT,
HfTransformType::IDENTITY,
HfTransformType::DCT2X2,
HfTransformType::DCT4X4,
HfTransformType::DCT16X16,
HfTransformType::DCT32X32,
HfTransformType::DCT16X8,
HfTransformType::DCT8X16,
HfTransformType::DCT32X8,
HfTransformType::DCT8X32,
HfTransformType::DCT32X16,
HfTransformType::DCT16X32,
HfTransformType::DCT4X8,
HfTransformType::DCT8X4,
HfTransformType::AFV0,
HfTransformType::AFV1,
HfTransformType::AFV2,
HfTransformType::AFV3,
HfTransformType::DCT64X64,
HfTransformType::DCT64X32,
HfTransformType::DCT32X64,
HfTransformType::DCT128X128,
HfTransformType::DCT128X64,
HfTransformType::DCT64X128,
HfTransformType::DCT256X256,
HfTransformType::DCT256X128,
HfTransformType::DCT128X256,
];
pub fn from_usize(idx: usize) -> Option<HfTransformType> {
HfTransformType::VALUES.get(idx).copied()
}
}
pub fn covered_blocks_x(transform: HfTransformType) -> u32 {
let lut: [u32; HfTransformType::CARDINALITY] = [
1, 1, 1, 1, 2, 4, 1, 2, 1, 4, 2, 4, 1, 1, 1, 1, 1, 1, 8, 4, 8, 16, 8, 16, 32, 16, 32,
];
lut[transform as usize]
}
pub fn covered_blocks_y(transform: HfTransformType) -> u32 {
let lut: [u32; HfTransformType::CARDINALITY] = [
1, 1, 1, 1, 2, 4, 2, 1, 4, 1, 4, 2, 1, 1, 1, 1, 1, 1, 8, 8, 4, 16, 16, 8, 32, 32, 16,
];
lut[transform as usize]
}
pub fn block_shape_id(transform: HfTransformType) -> u32 {
let lut: [u32; HfTransformType::CARDINALITY] = [
0, 1, 1, 1, 2, 3, 4, 4, 5, 5, 6, 6, 1, 1, 1, 1, 1, 1, 7, 8, 8, 9, 10, 10, 11, 12, 12,
];
lut[transform as usize]
}