1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/image/decoders/EXIF.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,76 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#ifndef MOZILLA_IMAGELIB_EXIF_H_
1.10 +#define MOZILLA_IMAGELIB_EXIF_H_
1.11 +
1.12 +#include <stdint.h>
1.13 +#include "mozilla/TypedEnum.h"
1.14 +#include "nsDebug.h"
1.15 +
1.16 +#include "Orientation.h"
1.17 +
1.18 +namespace mozilla {
1.19 +namespace image {
1.20 +
1.21 +MOZ_BEGIN_ENUM_CLASS(ByteOrder, uint8_t)
1.22 + Unknown,
1.23 + LittleEndian,
1.24 + BigEndian
1.25 +MOZ_END_ENUM_CLASS(ByteOrder)
1.26 +
1.27 +struct EXIFData
1.28 +{
1.29 + EXIFData() { }
1.30 + explicit EXIFData(Orientation aOrientation) : orientation(aOrientation) { }
1.31 +
1.32 + const Orientation orientation;
1.33 +};
1.34 +
1.35 +class EXIFParser
1.36 +{
1.37 +public:
1.38 + static EXIFData
1.39 + Parse(const uint8_t* aData, const uint32_t aLength)
1.40 + {
1.41 + EXIFParser parser;
1.42 + return parser.ParseEXIF(aData, aLength);
1.43 + }
1.44 +
1.45 +private:
1.46 + EXIFParser()
1.47 + : mStart(nullptr)
1.48 + , mCurrent(nullptr)
1.49 + , mLength(0)
1.50 + , mRemainingLength(0)
1.51 + , mByteOrder(ByteOrder::Unknown)
1.52 + { }
1.53 +
1.54 + EXIFData ParseEXIF(const uint8_t* aData, const uint32_t aLength);
1.55 + bool ParseEXIFHeader();
1.56 + bool ParseTIFFHeader(uint32_t& aIFD0OffsetOut);
1.57 + bool ParseIFD0(Orientation& aOrientationOut);
1.58 + bool ParseOrientation(uint16_t aType, uint32_t aCount, Orientation& aOut);
1.59 +
1.60 + bool Initialize(const uint8_t* aData, const uint32_t aLength);
1.61 + void Advance(const uint32_t aDistance);
1.62 + void JumpTo(const uint32_t aOffset);
1.63 +
1.64 + bool MatchString(const char* aString, const uint32_t aLength);
1.65 + bool MatchUInt16(const uint16_t aValue);
1.66 + bool ReadUInt16(uint16_t& aOut);
1.67 + bool ReadUInt32(uint32_t& aOut);
1.68 +
1.69 + const uint8_t* mStart;
1.70 + const uint8_t* mCurrent;
1.71 + uint32_t mLength;
1.72 + uint32_t mRemainingLength;
1.73 + ByteOrder mByteOrder;
1.74 +};
1.75 +
1.76 +}
1.77 +}
1.78 +
1.79 +#endif
