whiteoutlib 0.1.4

// SPDX-License-Identifier: BSD-3-Clause
// Copyright (c) 2026 Fernando Sahmkow

/// JPEG-specific Huffman codec facade.
///
/// The underlying bit I/O and Huffman table primitives now live in
/// src/whiteout/common/{bit_io.h, huffman_table.h}. This header re-exports
/// them under the original JPEG-local names for backward compatibility and
/// adds the standard JPEG Huffman table data (ITU-T T.81 Annex K).

#pragma once

#include <array>

#include <whiteout/common_types.h>

#include "jpeg_common.h"

// Unified bit I/O and Huffman table primitives.
#include "../../common/bit_io.h"
#include "../../common/huffman_table.h"

namespace whiteout::textures::jpeg {

// ============================================================================
// Type aliases — keep existing JPEG code compiling without changes.
// ============================================================================

using BitstreamReader = ::whiteout::MsbBitReader;
using BitstreamWriter = ::whiteout::MsbBitWriter;
using HuffmanTable = ::whiteout::MsbHuffmanTable;
using HuffmanCode = ::whiteout::HuffmanCode;
using HuffmanEncodeTable = ::whiteout::HuffmanEncodeTable;

// Re-export shared constants into the jpeg namespace.
inline constexpr auto& BIT_MASK = ::whiteout::BIT_MASK;
inline constexpr auto HUFFMAN_FAST_BITS = ::whiteout::HUFFMAN_FAST_BITS;

// ============================================================================
// Standard Huffman Tables (ITU-T T.81, Annex K)
// ============================================================================

/// DC luminance Huffman table (Table K.3).
inline constexpr std::array<u8, 16> DC_LUMA_COUNTS = {{
    0,
    1,
    5,
    1,
    1,
    1,
    1,
    1,
    1,
    0,
    0,
    0,
    0,
    0,
    0,
    0,
}};
inline constexpr std::array<u8, 12> DC_LUMA_SYMBOLS = {{
    0,
    1,
    2,
    3,
    4,
    5,
    6,
    7,
    8,
    9,
    10,
    11,
}};

/// AC luminance Huffman table (Table K.5).
inline constexpr std::array<u8, 16> AC_LUMA_COUNTS = {{
    0,
    2,
    1,
    3,
    3,
    2,
    4,
    3,
    5,
    5,
    4,
    4,
    0,
    0,
    1,
    0x7D,
}};
inline constexpr std::array<u8, 162> AC_LUMA_SYMBOLS = {{
    0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12, 0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61,
    0x07, 0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xA1, 0x08, 0x23, 0x42, 0xB1, 0xC1, 0x15, 0x52,
    0xD1, 0xF0, 0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0A, 0x16, 0x17, 0x18, 0x19, 0x1A, 0x25,
    0x26, 0x27, 0x28, 0x29, 0x2A, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x43, 0x44, 0x45,
    0x46, 0x47, 0x48, 0x49, 0x4A, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x63, 0x64,
    0x65, 0x66, 0x67, 0x68, 0x69, 0x6A, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A, 0x83,
    0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99,
    0x9A, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xB2, 0xB3, 0xB4, 0xB5, 0xB6,
    0xB7, 0xB8, 0xB9, 0xBA, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xD2, 0xD3,
    0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, 0xE1, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7, 0xE8,
    0xE9, 0xEA, 0xF1, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8, 0xF9, 0xFA,
}};

/// DC chrominance Huffman table (Table K.4).
inline constexpr std::array<u8, 16> DC_CHROMA_COUNTS = {{
    0,
    3,
    1,
    1,
    1,
    1,
    1,
    1,
    1,
    1,
    1,
    0,
    0,
    0,
    0,
    0,
}};
inline constexpr std::array<u8, 12> DC_CHROMA_SYMBOLS = {{
    0,
    1,
    2,
    3,
    4,
    5,
    6,
    7,
    8,
    9,
    10,
    11,
}};

/// AC chrominance Huffman table (Table K.6).
inline constexpr std::array<u8, 16> AC_CHROMA_COUNTS = {{
    0,
    2,
    1,
    2,
    4,
    4,
    3,
    4,
    7,
    5,
    4,
    4,
    0,
    1,
    2,
    0x77,
}};
inline constexpr std::array<u8, 162> AC_CHROMA_SYMBOLS = {{
    0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, 0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61,
    0x71, 0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91, 0xA1, 0xB1, 0xC1, 0x09, 0x23, 0x33,
    0x52, 0xF0, 0x15, 0x62, 0x72, 0xD1, 0x0A, 0x16, 0x24, 0x34, 0xE1, 0x25, 0xF1, 0x17, 0x18,
    0x19, 0x1A, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x43, 0x44,
    0x45, 0x46, 0x47, 0x48, 0x49, 0x4A, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x63,
    0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6A, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A,
    0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
    0x98, 0x99, 0x9A, 0xA2, 0xA3, 0xA4, 0xA5, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xB2, 0xB3, 0xB4,
    0xB5, 0xB6, 0xB7, 0xB8, 0xB9, 0xBA, 0xC2, 0xC3, 0xC4, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA,
    0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0xD9, 0xDA, 0xE2, 0xE3, 0xE4, 0xE5, 0xE6, 0xE7,
    0xE8, 0xE9, 0xEA, 0xF2, 0xF3, 0xF4, 0xF5, 0xF6, 0xF7, 0xF8, 0xF9, 0xFA,
}};

} // namespace whiteout::textures::jpeg