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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.
#ifndef LIB_JXL_COEFF_ORDER_H_
#define LIB_JXL_COEFF_ORDER_H_
#include <jxl/memory_manager.h>
#include <array>
#include <cstddef>
#include <cstdint>
#include "lib/jxl/base/compiler_specific.h"
#include "lib/jxl/base/status.h"
#include "lib/jxl/coeff_order_fwd.h"
#include "lib/jxl/frame_dimensions.h"
namespace jxl {
class BitReader;
// Those offsets get multiplied by kDCTBlockSize.
static constexpr size_t kCoeffOrderLimit = 6156;
static constexpr std::array<size_t, 3 * kNumOrders + 1> JXL_MAYBE_UNUSED
kCoeffOrderOffset = {
0, 1, 2, 3, 4, 5, 6, 10, 14, 18,
34, 50, 66, 68, 70, 72, 76, 80, 84, 92,
100, 108, 172, 236, 300, 332, 364, 396, 652, 908,
1164, 1292, 1420, 1548, 2572, 3596, 4620, 5132, 5644, kCoeffOrderLimit};
// TODO(eustas): rollback to constexpr once modern C++ becomes required.
#define CoeffOrderOffset(O, C) \
(kCoeffOrderOffset[3 * (O) + (C)] * kDCTBlockSize)
static JXL_MAYBE_UNUSED constexpr size_t kCoeffOrderMaxSize =
kCoeffOrderLimit * kDCTBlockSize;
// Mapping from AC strategy to order bucket. Strategies with different natural
// orders must have different buckets.
constexpr std::array<uint8_t, 27> kStrategyOrder = {
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,
};
constexpr JXL_MAYBE_UNUSED uint32_t kPermutationContexts = 8;
uint32_t CoeffOrderContext(uint32_t val);
Status DecodeCoeffOrders(JxlMemoryManager* memory_manager, uint16_t used_orders,
uint32_t used_acs, coeff_order_t* order,
BitReader* br);
Status DecodePermutation(JxlMemoryManager* memory_manager, size_t skip,
size_t size, coeff_order_t* order, BitReader* br);
} // namespace jxl
#endif // LIB_JXL_COEFF_ORDER_H_