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read_image_metadataReadImageMetadataReadImageMetadataread_image_metadataread_image_metadata🔗

Short description🔗

read_image_metadataReadImageMetadataReadImageMetadataread_image_metadataread_image_metadata — Read metadata from image files.

Signature🔗

read_image_metadata( string Format, tuple TagName, filename.read FileName, out tuple TagValue )void ReadImageMetadata( const HTuple& Format, const HTuple& TagName, const HTuple& FileName, HTuple* TagValue )static void HOperatorSet.ReadImageMetadata( HTuple format, HTuple tagName, HTuple fileName, out HTuple tagValue )def read_image_metadata( format: str, tag_name: str, file_name: str ) -> Union[int, float, str]

Herror read_image_metadata( const char* Format, const char* TagName, const char* FileName, char* TagValue )

Herror T_read_image_metadata( const Htuple Format, const Htuple TagName, const Htuple FileName, Htuple* TagValue )

static HTuple HImage::ReadImageMetadata( const HString& Format, const HTuple& TagName, const HString& FileName )

static HTuple HImage::ReadImageMetadata( const char* Format, const HTuple& TagName, const char* FileName )

static HTuple HImage::ReadImageMetadata( const wchar_t* Format, const HTuple& TagName, const wchar_t* FileName ) (Windows only)

static HTuple HImage.ReadImageMetadata( string format, HTuple tagName, string fileName )

Description🔗

The operator read_image_metadataReadImageMetadata reads the metadata of the file FileNamefileNamefile_name and returns the information in TagValuetagValuetag_value. With TagNametagNametag_name you specify, for which single tag or tuple of tags you want to retrieve the information. The parameter Formatformatformat specifies, in which format the metadata is encoded.

This operators supports for Formatformatformat the TIFF metadata formats 'tiff'"tiff" and 'bigtiff'"bigtiff". The file extension .tif is expected.

The following tags are readable:

 
TagNametagNametag_name TagValuetagValuetag_value data type
'tiff_aperture_value'"tiff_aperture_value" double
'tiff_copyright'"tiff_copyright" string
'tiff_date_time'"tiff_date_time" string
'tiff_exposure_time'"tiff_exposure_time" double
'tiff_image_description'"tiff_image_description" string
'tiff_light_source'"tiff_light_source" integer
'tiff_make'"tiff_make" string
'tiff_software'"tiff_software" string

Note, the operator returns an error in case the tag specified by TagNametagNametag_name has no value set.

You can retrieve all readable tags with the string 'tiff_tags_supported_for_reading'"tiff_tags_supported_for_reading" for TagNametagNametag_name as well as retrieve all writable tags with the string 'tiff_tags_supported_for_writing'"tiff_tags_supported_for_writing". Each of both strings can be used only as single value for TagNametagNametag_name.

Execution information🔗

Execution information

  • Multithreading type: reentrant (runs in parallel with non-exclusive operators).

  • Multithreading scope: global (may be called from any thread).

  • Processed without parallelization.

Parameters🔗

Formatformatformat (input_control) string → (string)HTuple (HString)HTuple (string)strHtuple (char*)

Graphic format.

Default: 'tiff'"tiff"
Suggested values: 'tiff', 'bigtiff'"tiff", "bigtiff"

TagNametagNametag_name (input_control) tuple → (string)HTuple (HString)HTuple (string)strHtuple (char*)

Name of the tag to be written in the image file.

Default: 'tiff_image_description'"tiff_image_description"
Suggested values: 'tiff_image_description', 'tiff_make', 'tiff_software', 'tiff_date_time', 'tiff_copyright', 'tiff_exposure_time', 'tiff_aperture_value', 'tiff_light_source', 'tiff_tags_supported_for_reading', 'tiff_tags_supported_for_writing'"tiff_image_description", "tiff_make", "tiff_software", "tiff_date_time", "tiff_copyright", "tiff_exposure_time", "tiff_aperture_value", "tiff_light_source", "tiff_tags_supported_for_reading", "tiff_tags_supported_for_writing"

FileNamefileNamefile_name (input_control) filename.read → (string)HTuple (HString)HTuple (string)strHtuple (char*)

Name of image file.

File extension: .tif, .tiff

TagValuetagValuetag_value (output_control) tuple → (string / integer / real)HTuple (HString / Hlong / double)HTuple (string / int / long / double)Union[int, float, str]Htuple (char* / Hlong / double)

Output tag value read from the image file.

Result🔗

If TagValuetagValuetag_value can be correctly read for the specified input parameters the operator read_image_metadataReadImageMetadata returns the value 2 (H_MSG_TRUE). Otherwise an exception is raised. In this case, an extended error information, as e.g., the causative tag, may be set and can be queried with the operator get_extended_error_infoGetExtendedErrorInfo.

Combinations with other operators🔗

Combinations

Possible predecessors

write_image_metadataWriteImageMetadata

Possible successors

read_imageReadImage

Module🔗

Foundation