diff options
Diffstat (limited to 'third_party/jpeg-xl/lib/jxl/coeff_order.h')
-rw-r--r-- | third_party/jpeg-xl/lib/jxl/coeff_order.h | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/third_party/jpeg-xl/lib/jxl/coeff_order.h b/third_party/jpeg-xl/lib/jxl/coeff_order.h new file mode 100644 index 0000000000..fb32499f2f --- /dev/null +++ b/third_party/jpeg-xl/lib/jxl/coeff_order.h @@ -0,0 +1,64 @@ +// 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 <stddef.h> +#include <stdint.h> + +#include "lib/jxl/ac_strategy.h" +#include "lib/jxl/base/compiler_specific.h" +#include "lib/jxl/base/status.h" +#include "lib/jxl/coeff_order_fwd.h" +#include "lib/jxl/common.h" +#include "lib/jxl/dct_util.h" + +namespace jxl { + +class BitReader; + +// Those offsets get multiplied by kDCTBlockSize. +static constexpr size_t 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, 6156, +}; +static_assert(3 * kNumOrders + 1 == + sizeof(kCoeffOrderOffset) / sizeof(*kCoeffOrderOffset), + "Update this array when adding or removing order types."); + +static constexpr size_t CoeffOrderOffset(size_t order, size_t c) { + return kCoeffOrderOffset[3 * order + c] * kDCTBlockSize; +} + +static constexpr size_t kCoeffOrderMaxSize = + kCoeffOrderOffset[3 * kNumOrders] * kDCTBlockSize; + +// Mapping from AC strategy to order bucket. Strategies with different natural +// orders must have different buckets. +constexpr uint8_t 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, +}; + +static_assert(AcStrategy::kNumValidStrategies == + sizeof(kStrategyOrder) / sizeof(*kStrategyOrder), + "Update this array when adding or removing AC strategies."); + +constexpr uint32_t kPermutationContexts = 8; + +uint32_t CoeffOrderContext(uint32_t val); + +Status DecodeCoeffOrders(uint16_t used_orders, uint32_t used_acs, + coeff_order_t* order, BitReader* br); + +Status DecodePermutation(size_t skip, size_t size, coeff_order_t* order, + BitReader* br); + +} // namespace jxl + +#endif // LIB_JXL_COEFF_ORDER_H_ |