Stores and parses EXIF and XMP metadata extracted from a JPEG image stream. More...

Collaboration diagram for EXIFInfo:

Classes
struct	Calibration_t
	Camera calibration information derived from EXIF metadata. More...
struct	Geolocation_t
	GPS and flight telemetry information embedded in the image file. More...
struct	GPano_t
	Google Photo Sphere (GPano) spherical metadata. More...
struct	LensInfo_t
	Lens information extracted from EXIF metadata. More...
struct	MicroVideo_t
	Google camera micro-video metadata embedded in the image file. More...

Public Member Functions
	EXIFInfo ()
	Default constructor.
	EXIFInfo (const uint8_t *data, unsigned length)
	Constructs and immediately parses EXIF/XMP data from a raw memory buffer.
	EXIFInfo (EXIFStream &stream)
	Constructs and immediately parses EXIF/XMP data from the given EXIFStream.
	EXIFInfo (std::istream &stream)
	Constructs and immediately parses EXIF/XMP data from a standard input stream.
void	clear ()
	Resets all data members to their default values.
int	parseFrom (const uint8_t *data, unsigned length)
	Parses EXIF and XMP metadata from a JPEG image in a raw memory buffer.
int	parseFrom (EXIFStream &stream)
	Parses EXIF and XMP metadata from a JPEG image provided via an EXIFStream.
int	parseFrom (std::istream &stream)
	Parses EXIF and XMP metadata from a JPEG image provided via a standard input stream.
int	parseFromEXIFSegment (const uint8_t *buf, unsigned len)
	Parses metadata from a standalone EXIF segment (blob starting with "Exif\0\0").
int	parseFromXMPSegment (const uint8_t *buf, unsigned len)
	Parses metadata from a standalone XMP segment.
int	parseFromXMPSegmentXML (const char *szXML, unsigned len)
	Parses metadata from raw XMP XML content.

Public Attributes
double	ApertureValue
	Lens aperture (APEX value).
uint16_t	BitsPerSample
	Number of bits per component.
double	BrightnessValue
	Brightness value (APEX).
struct EXIFInfo::Calibration_t	Calibration
	Camera calibration data.
String	Copyright
	File copyright information.
String	DateTime
	File change date and time.
String	DateTimeDigitized
	Digitization date and time (may not exist).
String	DateTimeOriginal
	Original capture date and time (may not exist).
double	ExposureBiasValue
	Exposure bias value in EV.
uint16_t	ExposureProgram
	Exposure program used.
double	ExposureTime
	Exposure time in seconds.
uint32_t	Fields
	Bitmask of FieldCode values indicating which metadata categories are available.
uint16_t	Flash
	Flash status bitmask.
double	FNumber
	F-number (f-stop) of the lens.
double	FocalLength
	Focal length of the lens in millimeters.
struct EXIFInfo::Geolocation_t	GeoLocation
	GPS and flight telemetry data.
struct EXIFInfo::GPano_t	GPano
	Spherical/panorama metadata.
String	ImageDescription
	Image description.
uint32_t	ImageHeight
	Image height reported in EXIF data (pixels).
uint32_t	ImageWidth
	Image width reported in EXIF data (pixels).
uint16_t	ISOSpeedRatings
	ISO speed rating.
struct EXIFInfo::LensInfo_t	LensInfo
	Lens metadata.
uint16_t	LightSource
	Kind of light source.
String	Make
	Camera manufacturer's name.
uint16_t	MeteringMode
	Metering mode.
struct EXIFInfo::MicroVideo_t	MicroVideo
	Embedded micro-video metadata.
String	Model
	Camera model.
uint16_t	Orientation
	Image orientation (EXIF tag 0x0112).
uint16_t	ProjectionType
	Projection type.
uint32_t	RelatedImageHeight
	Original image height reported in EXIF data (pixels).
uint32_t	RelatedImageWidth
	Original image width reported in EXIF data (pixels).
uint16_t	ResolutionUnit
	Unit of measurement for XResolution and YResolution.
String	SerialNumber
	Serial number of the camera body.
double	ShutterSpeedValue
	Shutter speed (APEX value, reciprocal of exposure time).
String	Software
	Software used to create/modify the image.
Buffer< uint16_t >	SubjectArea
	Location and area of the main subject relative to upper-left origin.
double	SubjectDistance
	Distance to the focus point in meters.
String	SubSecTimeOriginal
	Sub-second time of original capture.
double	XResolution
	Number of pixels per ResolutionUnit in the X (width) direction.
double	YResolution
	Number of pixels per ResolutionUnit in the Y (height) direction.

Detailed Description

Stores and parses EXIF and XMP metadata extracted from a JPEG image stream.

After construction or a call to one of the parseFrom() overloads, the public data members are populated with the metadata values found in the image. Use the Fields member to check which categories of data were successfully parsed.

Definition at line 68 of file TinyExif.h.

Constructor & Destructor Documentation

◆ EXIFInfo() [1/4]

EXIFInfo::EXIFInfo ( )

Default constructor.

Initializes all fields to their default (empty/zero) values.

◆ EXIFInfo() [2/4]

EXIFInfo::EXIFInfo ( EXIFStream & stream )

Constructs and immediately parses EXIF/XMP data from the given EXIFStream.

Parameters

[in] stream The stream interface providing JPEG image data.

◆ EXIFInfo() [3/4]

EXIFInfo::EXIFInfo ( std::istream & stream )

Constructs and immediately parses EXIF/XMP data from a standard input stream.

Parameters

[in] stream A std::istream opened in binary mode containing a JPEG image.

◆ EXIFInfo() [4/4]

EXIFInfo::EXIFInfo	(	const uint8_t *	data,
		unsigned	length )

Constructs and immediately parses EXIF/XMP data from a raw memory buffer.

Parameters

[in]	data	Pointer to the JPEG image data.
[in]	length	Size of the data buffer in bytes.

Member Function Documentation

◆ clear()

void EXIFInfo::clear ( )

Resets all data members to their default values.

Should be called before parsing a new stream to ensure stale data from a previous parse does not persist.

◆ parseFrom() [1/3]

int EXIFInfo::parseFrom	(	const uint8_t *	data,
		unsigned	length )

Parses EXIF and XMP metadata from a JPEG image in a raw memory buffer.

Parameters

[in]	data	Pointer to the JPEG image data.
[in]	length	Size of the data buffer in bytes.

Returns: PARSE_SUCCESS (0) on success, or one of the PARSE_* error codes on failure.

◆ parseFrom() [2/3]

int EXIFInfo::parseFrom ( EXIFStream & stream )

Parses EXIF and XMP metadata from a JPEG image provided via an EXIFStream.

Parameters

[in] stream The stream interface providing JPEG image data.

Returns: PARSE_SUCCESS (0) on success, or one of the PARSE_* error codes on failure.

◆ parseFrom() [3/3]

int EXIFInfo::parseFrom ( std::istream & stream )

Parses EXIF and XMP metadata from a JPEG image provided via a standard input stream.

Parameters

[in] stream A std::istream opened in binary mode containing a JPEG image.

Returns: PARSE_SUCCESS (0) on success, or one of the PARSE_* error codes on failure.

◆ parseFromEXIFSegment()

int EXIFInfo::parseFromEXIFSegment	(	const uint8_t *	buf,
		unsigned	len )

Parses metadata from a standalone EXIF segment (blob starting with "Exif\0\0").

This is used internally by parseFrom() but can be called directly when only the EXIF segment is available.

Parameters

[in]	buf	Pointer to the EXIF segment data.
[in]	len	Size of the EXIF segment in bytes.

Returns: PARSE_SUCCESS (0) on success, or one of the PARSE_* error codes on failure.

◆ parseFromXMPSegment()

int EXIFInfo::parseFromXMPSegment	(	const uint8_t *	buf,
		unsigned	len )

Parses metadata from a standalone XMP segment.

The blob should start with "http://ns.adobe.com/xap/1.0/\0". Used internally by parseFrom() but can be called for special cases.

Parameters

[in]	buf	Pointer to the XMP segment data.
[in]	len	Size of the XMP segment in bytes.

Returns: PARSE_SUCCESS (0) on success, or one of the PARSE_* error codes on failure.

◆ parseFromXMPSegmentXML()

int EXIFInfo::parseFromXMPSegmentXML	(	const char *	szXML,
		unsigned	len )

Parses metadata from raw XMP XML content.

Parameters

[in]	szXML	Pointer to the null-terminated XMP XML string.
[in]	len	Length of the XML string in bytes.

Returns: PARSE_SUCCESS (0) on success, or one of the PARSE_* error codes on failure.

Member Data Documentation

◆ ExposureProgram

uint16_t EXIFInfo::ExposureProgram

Exposure program used.

0: not defined, 1: manual, 2: normal program, 3: aperture priority, 4: shutter priority, 5: creative, 6: action, 7: portrait, 8: landscape

Definition at line 212 of file TinyExif.h.

◆ Flash

uint16_t EXIFInfo::Flash

Flash status bitmask.

Bit 0: flash fired. Bits 1-2: return light status. Bits 3-4: flash mode. Bit 5: flash function present. Bit 6: red-eye reduction supported.

Definition at line 223 of file TinyExif.h.

◆ LightSource

uint16_t EXIFInfo::LightSource

Kind of light source.

0: unknown, 1: daylight, 2: fluorescent, 3: tungsten, 4: flash, 9-15: various daylight/fluorescent types, 17-23: standard lights A-C and D-series, 24: ISO studio tungsten

Definition at line 230 of file TinyExif.h.

◆ MeteringMode

uint16_t EXIFInfo::MeteringMode

Metering mode.

0: unknown, 1: average, 2: center weighted average, 3: spot, 4: multi-spot, 5: pattern, 6: partial

Definition at line 227 of file TinyExif.h.

◆ Orientation

uint16_t EXIFInfo::Orientation

Image orientation (EXIF tag 0x0112).

0: unspecified, 1: upper left, 3: lower right, 6: upper right, 8: lower left, 9: undefined

Definition at line 196 of file TinyExif.h.

◆ ProjectionType

uint16_t EXIFInfo::ProjectionType

Projection type.

0: unknown, 1: perspective, 2: equirectangular/spherical

Definition at line 234 of file TinyExif.h.

◆ ResolutionUnit

uint16_t EXIFInfo::ResolutionUnit

Unit of measurement for XResolution and YResolution.

1: no absolute unit, 2: inch, 3: centimeter

Definition at line 201 of file TinyExif.h.

◆ SubjectArea

Buffer<uint16_t> EXIFInfo::SubjectArea

Location and area of the main subject relative to upper-left origin.

2 values: XY coordinates; 3 values: circle (X, Y, diameter); 4 values: rectangle (X, Y, width, height)

Definition at line 236 of file TinyExif.h.

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

Design/Headers/TinyExif.h

Classes

Public Member Functions

Public Attributes

Detailed Description

Constructor & Destructor Documentation

◆ EXIFInfo() [1/4]

◆ EXIFInfo() [2/4]

◆ EXIFInfo() [3/4]

◆ EXIFInfo() [4/4]

Member Function Documentation

◆ clear()

◆ parseFrom() [1/3]

◆ parseFrom() [2/3]

◆ parseFrom() [3/3]

◆ parseFromEXIFSegment()

◆ parseFromXMPSegment()

◆ parseFromXMPSegmentXML()

Member Data Documentation

◆ ExposureProgram

◆ Flash

◆ LightSource

◆ MeteringMode

◆ Orientation

◆ ProjectionType

◆ ResolutionUnit

◆ SubjectArea