Exiv2::ExvImage Class Reference

Helper class to access Exiv2 files. More...

#include <jpgimage.hpp>

Inheritance diagram for Exiv2::ExvImage:

Public Member Functions

Creators
 ExvImage (BasicIo::UniquePtr io, bool create)
 Constructor that can either open an existing EXV image or create a new image from scratch. If a new image is to be created, any existing data is overwritten. Since the constructor can not return a result, callers should check the good() method after object construction to determine success or failure. More...
 
- Public Member Functions inherited from Exiv2::JpegBase
void readMetadata () override
 Read all metadata supported by a specific image format from the image. Before this method is called, the image metadata will be cleared. More...
 
void writeMetadata () override
 Write metadata back to the image. More...
 
void printStructure (std::ostream &out, PrintStructureOption option, size_t depth) override
 Print out the structure of image file. More...
 
- Public Member Functions inherited from Exiv2::Image
 Image (ImageType type, uint16_t supportedMetadata, BasicIo::UniquePtr io)
 Constructor taking the image type, a bitmap of the supported metadata types and an auto-pointer that owns an IO instance. See subclass constructor doc.
 
virtual ~Image ()=default
 Virtual Destructor.
 
ByteOrder byteOrder () const
 Return the byte order in which the Exif metadata of the image is encoded. Initially, it is not set (invalidByteOrder).
 
bool good () const
 Check if the Image instance is valid. Use after object construction. More...
 
virtual uint32_t pixelWidth () const
 Return the pixel width of the image.
 
virtual uint32_t pixelHeight () const
 Return the pixel height of the image.
 
virtual const ExifDataexifData () const
 Returns an ExifData instance containing currently buffered Exif data. More...
 
virtual const IptcDataiptcData () const
 Returns an IptcData instance containing currently buffered IPTC data. More...
 
virtual const XmpDataxmpData () const
 Returns an XmpData instance containing currently buffered XMP data. More...
 
virtual std::string comment () const
 Return a copy of the image comment. May be an empty string.
 
virtual const std::string & xmpPacket () const
 Return the raw XMP packet as a string.
 
virtual BasicIoio () const
 Return a reference to the BasicIo instance being used for Io. More...
 
AccessMode checkMode (MetadataId metadataId) const
 Returns the access mode, i.e., the metadata functions, which this image supports for the metadata type metadataId. More...
 
bool supportsMetadata (MetadataId metadataId) const
 Check if image supports a particular type of metadata. This method is deprecated. Use checkMode() instead.
 
bool writeXmpFromPacket () const
 Return the flag indicating the source when writing XMP metadata.
 
const NativePreviewListnativePreviews () const
 Return list of native previews. This is meant to be used only by the PreviewManager.
 
void setTypeSupported (ImageType imageType, uint16_t supportedMetadata)
 set type support for this image format
 
ImageType imageType () const
 set type support for this image format
 
 Image (const Image &)=delete
 Copy constructor.
 
Imageoperator= (const Image &)=delete
 Assignment operator.
 
virtual void setExifData (const ExifData &exifData)
 Assign new Exif data. The new Exif data is not written to the image until the writeMetadata() method is called. More...
 
virtual void clearExifData ()
 Erase any buffered Exif data. Exif data is not removed from the actual image until the writeMetadata() method is called.
 
virtual void setIptcData (const IptcData &iptcData)
 Assign new IPTC data. The new IPTC data is not written to the image until the writeMetadata() method is called. More...
 
virtual void clearIptcData ()
 Erase any buffered IPTC data. IPTC data is not removed from the actual image until the writeMetadata() method is called.
 
virtual void setXmpPacket (const std::string &xmpPacket)
 Assign a raw XMP packet. The new XMP packet is not written to the image until the writeMetadata() method is called. More...
 
virtual void clearXmpPacket ()
 Erase the buffered XMP packet. XMP data is not removed from the actual image until the writeMetadata() method is called. More...
 
virtual void setXmpData (const XmpData &xmpData)
 Assign new XMP data. The new XMP data is not written to the image until the writeMetadata() method is called. More...
 
virtual void clearXmpData ()
 Erase any buffered XMP data. XMP data is not removed from the actual image until the writeMetadata() method is called. More...
 
virtual void setComment (const std::string &comment)
 Set the image comment. The comment is written to the image when writeMetadata() is called.
 
virtual void clearComment ()
 Erase any buffered comment. Comment is not removed from the actual image until the writeMetadata() method is called.
 
virtual void setIccProfile (DataBuf &&iccProfile, bool bTestValid=true)
 Set the image iccProfile. The new profile is not written to the image until the writeMetadata() method is called. More...
 
virtual void clearIccProfile ()
 Erase iccProfile. the profile is not removed from the actual image until the writeMetadata() method is called.
 
virtual bool iccProfileDefined ()
 Returns the status of the ICC profile in the image instance.
 
virtual const DataBuficcProfile () const
 return iccProfile
 
virtual void setMetadata (const Image &image)
 Copy all existing metadata from source Image. The data is copied into internal buffers and is not written to the image until the writeMetadata() method is called. More...
 
virtual void clearMetadata ()
 Erase all buffered metadata. Metadata is not removed from the actual image until the writeMetadata() method is called.
 
virtual ExifDataexifData ()
 Returns an ExifData instance containing currently buffered Exif data. More...
 
virtual IptcDataiptcData ()
 Returns an IptcData instance containing currently buffered IPTC data. More...
 
virtual XmpDataxmpData ()
 Returns an XmpData instance containing currently buffered XMP data. More...
 
virtual std::string & xmpPacket ()
 Return a modifiable reference to the raw XMP packet.
 
void writeXmpFromPacket (bool flag)
 Determine the source when writing XMP. More...
 
void setByteOrder (ByteOrder byteOrder)
 Set the byte order to encode the Exif metadata in. More...
 
void printTiffStructure (BasicIo &io, std::ostream &out, PrintStructureOption option, size_t depth, size_t offset=0)
 Print out the structure of image file. More...
 
void printIFDStructure (BasicIo &io, std::ostream &out, Exiv2::PrintStructureOption option, size_t start, bool bSwap, char c, size_t depth)
 Print out the structure of a TIFF IFD.
 

Friends

EXIV2API bool isExvType (BasicIo &iIo, bool advance)
 Check if the file iIo is an EXV file.
 

Manipulators

int writeHeader (BasicIo &outIo) const override
 Writes the image header (aka signature) to the BasicIo instance. More...
 

Accessors

std::string mimeType () const override
 Return the MIME type of the image. More...
 
bool isThisType (BasicIo &iIo, bool advance) const override
 Determine if the content of the BasicIo instance is of the type supported by this class. More...
 

Additional Inherited Members

- Public Types inherited from Exiv2::Image
using UniquePtr = std::unique_ptr< Image >
 Image auto_ptr type.
 
- Static Public Member Functions inherited from Exiv2::Image
static bool isBigEndianPlatform ()
 is the host platform bigEndian
 
static bool isLittleEndianPlatform ()
 is the host platform littleEndian
 
static bool isStringType (uint16_t type)
 
static bool isShortType (uint16_t type)
 
static bool isLongType (uint16_t type)
 
static bool isLongLongType (uint16_t type)
 
static bool isRationalType (uint16_t type)
 
static bool is2ByteType (uint16_t type)
 
static bool is4ByteType (uint16_t type)
 
static bool is8ByteType (uint16_t type)
 
static bool isPrintXMP (uint16_t type, Exiv2::PrintStructureOption option)
 
static bool isPrintICC (uint16_t type, Exiv2::PrintStructureOption option)
 
static uint64_t byteSwap (uint64_t value, bool bSwap)
 
static uint32_t byteSwap (uint32_t value, bool bSwap)
 
static uint16_t byteSwap (uint16_t value, bool bSwap)
 
static uint16_t byteSwap2 (const DataBuf &buf, size_t offset, bool bSwap)
 
static uint32_t byteSwap4 (const DataBuf &buf, size_t offset, bool bSwap)
 
static uint64_t byteSwap8 (const DataBuf &buf, size_t offset, bool bSwap)
 
- Protected Member Functions inherited from Exiv2::JpegBase
 JpegBase (ImageType type, BasicIo::UniquePtr io, bool create, const byte initData[], size_t dataSize)
 Constructor that can either open an existing image or create a new image from scratch. If a new image is to be created, any existing data is overwritten. More...
 
- Protected Member Functions inherited from Exiv2::Image
const std::string & tagName (uint16_t tag)
 Return tag name for given tag id.
 
- Static Protected Member Functions inherited from Exiv2::Image
static const char * typeName (uint16_t tag)
 Return tag type for given tag id.
 
- Protected Attributes inherited from Exiv2::JpegBase
int num_color_components_ {-1}
 image number of color components
 
std::string sof_encoding_process_
 image encoding process
 
- Protected Attributes inherited from Exiv2::Image
BasicIo::UniquePtr io_
 Image data IO pointer.
 
ExifData exifData_
 Exif data container.
 
IptcData iptcData_
 IPTC data container.
 
XmpData xmpData_
 XMP data container.
 
DataBuf iccProfile_
 ICC buffer (binary data)
 
std::string comment_
 User comment.
 
std::string xmpPacket_
 XMP packet.
 
uint32_t pixelWidth_ {0}
 image pixel width
 
uint32_t pixelHeight_ {0}
 image pixel height
 
NativePreviewList nativePreviews_
 list of native previews
 

Detailed Description

Helper class to access Exiv2 files.

Constructor & Destructor Documentation

◆ ExvImage()

Exiv2::ExvImage::ExvImage ( BasicIo::UniquePtr  io,
bool  create 
)

Constructor that can either open an existing EXV image or create a new image from scratch. If a new image is to be created, any existing data is overwritten. Since the constructor can not return a result, callers should check the good() method after object construction to determine success or failure.

Parameters
ioAn auto-pointer that owns a BasicIo instance used for reading and writing image metadata. Important: The constructor takes ownership of the passed in BasicIo instance through the auto-pointer. Callers should not continue to use the BasicIo instance after it is passed to this method. Use the Image::io() method to get a temporary reference.
createSpecifies if an existing image should be read (false) or if a new file should be created (true).

Member Function Documentation

◆ isThisType()

bool Exiv2::ExvImage::isThisType ( BasicIo iIo,
bool  advance 
) const
overrideprotectedvirtual

Determine if the content of the BasicIo instance is of the type supported by this class.

The advance flag determines if the read position in the stream is moved (see below). This applies only if the type matches and the function returns true. If the type does not match, the stream position is not changed. However, if reading from the stream fails, the stream position is undefined. Consult the stream state to obtain more information in this case.

Parameters
iIoBasicIo instance to read from.
advanceFlag indicating whether the position of the io should be advanced by the number of characters read to analyse the data (true) or left at its original position (false). This applies only if the type matches.
Returns
true if the data matches the type of this class;
false if the data does not match

Implements Exiv2::JpegBase.

◆ mimeType()

std::string Exiv2::ExvImage::mimeType ( ) const
overridevirtual

Return the MIME type of the image.

Note
For each supported image format, the library knows only one MIME type. This may not be the most specific MIME type for that format. In particular, several RAW formats are variants of the TIFF format with the same magic as TIFF itself. Class TiffImage handles most of them and thus they all have MIME type "image/tiff", although a more specific MIME type may exist (e.g., "image/x-nikon-nef").

Implements Exiv2::Image.

◆ writeHeader()

int Exiv2::ExvImage::writeHeader ( BasicIo oIo) const
overrideprotectedvirtual

Writes the image header (aka signature) to the BasicIo instance.

Parameters
oIoBasicIo instance that the header is written to.
Returns
0 if successful;
4 if the output file can not be written to

Implements Exiv2::JpegBase.


The documentation for this class was generated from the following file: