ljpegdecompressor.hpp

/* -*- Mode: C++ -*- */
/*
 * libopenraw - ljpegdecompressor.h
 *
 * Copyright (C) 2007-2022 Hubert Figuière
 *
 * This library is free software: you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library.  If not, see
 * <http://www.gnu.org/licenses/>.
 */
 
#pragma once
 
#include <stddef.h>
#include <sys/types.h>
#include <stdint.h>
 
#include <vector>
 
#include "decompressor.hpp"
 
namespace OpenRaw {
 
class RawData;
 
namespace Internals {
 
class Stream;
class RawContainer;
struct HuffmanTable;
struct DecompressInfo;
 
typedef int16_t ComponentType;
typedef ComponentType *MCU;
 
 
class LJpegDecompressor
    : public Decompressor
{
public:
    LJpegDecompressor(IO::Stream *,
                      RawContainer *);
    virtual ~LJpegDecompressor();
 
    virtual RawDataPtr decompress() override;
    void setSlices(const std::vector<uint16_t> & slices);
    bool isSliced() const
        {
            return m_slices.size() > 1;
        }
private:
 
    int32_t readBits(IO::Stream * s, uint16_t bitCount);
    int32_t show_bits8(IO::Stream * s);
    void flush_bits(uint16_t nbits);
    int32_t get_bits(uint16_t nbits);
    int32_t get_bit();
 
    typedef enum {
        M_SOF0 = 0xc0,
        M_SOF1 = 0xc1,
        M_SOF2 = 0xc2,
        M_SOF3 = 0xc3,
 
        M_SOF5 = 0xc5,
        M_SOF6 = 0xc6,
        M_SOF7 = 0xc7,
 
        M_JPG = 0xc8,
        M_SOF9 = 0xc9,
        M_SOF10 = 0xca,
        M_SOF11 = 0xcb,
 
        M_SOF13 = 0xcd,
        M_SOF14 = 0xce,
        M_SOF15 = 0xcf,
 
        M_DHT = 0xc4,
 
        M_DAC = 0xcc,
 
        M_RST0 = 0xd0,
        M_RST1 = 0xd1,
        M_RST2 = 0xd2,
        M_RST3 = 0xd3,
        M_RST4 = 0xd4,
        M_RST5 = 0xd5,
        M_RST6 = 0xd6,
        M_RST7 = 0xd7,
 
        M_SOI = 0xd8,
        M_EOI = 0xd9,
        M_SOS = 0xda,
        M_DQT = 0xdb,
        M_DNL = 0xdc,
        M_DRI = 0xdd,
        M_DHP = 0xde,
        M_EXP = 0xdf,
 
        M_APP0 = 0xe0,
        M_APP15 = 0xef,
 
        M_JPG0 = 0xf0,
        M_JPG13 = 0xfd,
        M_COM = 0xfe,
 
        M_TEM = 0x01,
 
        M_ERROR = 0x100
    } JpegMarker;
 
    void DecoderStructInit (DecompressInfo *dcPtr) noexcept(false);
    void HuffDecoderInit (DecompressInfo *dcPtr) noexcept(false);
    void ProcessRestart (DecompressInfo *dcPtr) noexcept(false);
    void DecodeFirstRow(DecompressInfo *dcPtr,
                        MCU *curRowBuf);
    void DecodeImage(DecompressInfo *dcPtr);
    int32_t QuickPredict(int32_t col, int16_t curComp,
                         MCU *curRowBuf, MCU *prevRowBuf,
                         int32_t psv);
    void PmPutRow(MCU* RowBuf, int32_t numComp, int32_t numCol, int32_t Pt);
    void GetDht (DecompressInfo *dcPtr) noexcept(false);
    void GetDri (DecompressInfo *dcPtr) noexcept(false);
    void GetSof (DecompressInfo *dcPtr) noexcept(false);
    void GetSos (DecompressInfo *dcPtr) noexcept(false);
    JpegMarker ProcessTables (DecompressInfo *dcPtr);
    void ReadFileHeader (DecompressInfo *dcPtr) noexcept(false);
    int32_t ReadScanHeader (DecompressInfo *dcPtr);
    int32_t HuffDecode(HuffmanTable *htbl);
 
    std::vector<uint16_t> m_slices;
 
    MCU *m_mcuROW1, *m_mcuROW2;
    MCU m_buf1, m_buf2;
 
    void fillBitBuffer (IO::Stream * s, uint16_t nbits);
    uint16_t m_bitsLeft;
    uint32_t m_getBuffer;
    RawDataPtr m_output;
 
    LJpegDecompressor(const LJpegDecompressor& f) = delete;
    LJpegDecompressor & operator=(const LJpegDecompressor&) = delete;
};
 
}
}
 
/*
  Local Variables:
  mode:c++
  c-file-style:"stroustrup"
  c-file-offsets:((innamespace . 0))
  indent-tabs-mode:nil
  fill-column:80
  End:
*/