1dfb065a9c
The marker bit is VP9-only, so move that into a new initialize_vp9() function. finish_decode() is VP9-only, so rename that to finish_decode_vp9().
45 lines
1.2 KiB
C++
45 lines
1.2 KiB
C++
/*
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* Copyright (c) 2021, Hunter Salyer <thefalsehonesty@gmail.com>
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* Copyright (c) 2022, Gregory Bertilson <zaggy1024@gmail.com>
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*
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* SPDX-License-Identifier: BSD-2-Clause
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*/
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#pragma once
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#include <AK/BitStream.h>
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#include <AK/Error.h>
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#include <AK/Optional.h>
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#include <AK/Types.h>
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namespace Gfx {
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// Can decode bitstreams encoded with VP8's and VP9's arithmetic boolean encoder.
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class BooleanDecoder {
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public:
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static ErrorOr<BooleanDecoder> initialize(MaybeOwned<BigEndianInputBitStream> bit_stream, size_t size_in_bytes);
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/* (9.2) */
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static ErrorOr<BooleanDecoder> initialize_vp9(MaybeOwned<BigEndianInputBitStream> bit_stream, size_t size_in_bytes);
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ErrorOr<bool> read_bool(u8 probability);
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ErrorOr<u8> read_literal(u8 bits);
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ErrorOr<void> finish_decode_vp9();
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private:
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BooleanDecoder(MaybeOwned<BigEndianInputBitStream>&& bit_stream, u8 value, u8 range, u64 bits_left)
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: m_bit_stream(move(bit_stream))
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, m_value(value)
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, m_range(range)
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, m_bits_left(bits_left)
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{
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}
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MaybeOwned<BigEndianInputBitStream> m_bit_stream;
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u8 m_value { 0 };
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u8 m_range { 0 };
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u64 m_bits_left { 0 };
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};
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}
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