- Correspondence between tags and constants
- Managing errors
In french: ImageInfoValeur
Returns the value of an Exif tag for the image used.
Remark: The Exif (EXchangeable Image File) information is included in the image file. This standard defines a set of tags used to store information about the image: date, width, orientation, camera model, shutter speed, distance, exposure time, ...
TagList is string
MyTag is int
i is int = 1
// Retrieve the available tags for
// the JPEG image displayed in the "IMG_MyImageControl" control
TagList = ImageInfoList(IMG_MyImageControl)
WHILE ExtractString(TagList, i, CR) <> EOT
// Retrieve each tag
MyTag = ExtractString(TagList, i, CR)
// Add the tag and its value into TABLE_MyTable
TableAddLine(TABLE_MyTable, MyTag, ...
ImgPath is string = "C:\My Images\MyImage.JPG"
// Find out the creation date of this image
Info("Creation date: " + ImageInfoValue(ImgPath, imgDate) + CR + ...
"Lightness: " + ImageInfoValue(ImgPath, imgBrightness) + CR + ...
"Focal length: " + ImageInfoValue(ImgPath, imgFocalLength) + CR + ...
"Aperture: " + ImageInfoValue(ImgPath, imgAperture))
// Close the image file
<Result> = ImageInfoValue(<Image> , <Tag>)
Value of the specified tag for the image used.
<Image>: Character string (with or without quotes)
Image to use. This image can correspond to:
- an image file (JPEG or TIFF format): specify the name and the full (or relative) path of the file. A UNC path can be used.
In this case, the file must be closed by ImageInfoClose.
- an image (JPEG or TIFF format) displayed in an Image control: specify the name of the Image control.
- an image (JPEG or TIFF format) found in an image memo: specify this image memo.
- an image (JPEG or TIFF format) found in a binary string: specify this binary string.
<Tag>: Constant or integer
Tag whose value is requested. This tag can correspond to:
- an integer given by ImageInfoList.
- a WLanguage constant. See "Correspondence between tags and constants" for more details.
Correspondence between tags and constants
The table below presents the correspondence between tags and WLanguage constants.
|37510||imgComment||Character string |
Comments about the image
Compression of the image in bits/pixel
|33432||imgCopyright||Character string |
Copyright of the image
Date and time of the image in YYYY:MM:DD HH:MM:SS format
|270||imgDescription||Character string |
Distance from the subject in meters
Exposure bias in APEX
Status of the flash during the shot:
- 0: Flash off.
- 1: Flash on.
- 5: Flash on and light not detected.
- 7: Flash on and light detected.
Height of image in pixels
Width of image in pixels
Name of the software that was used to record the image.
Focal length in millimeters
Brightness of the image in APEX
|271||imgDeviceMark||Character string |
Mark of the camera that took the photo
|272||imgDeviceModel||Character string |
Model of camera that took the photo
- 0: unknown.
- 1: average.
- 2: average centered.
- 3: point.
- 4: multipoint.
- 5: pattern.
- 6: partial.
- 7 to 254: reserved.
- 255: other.
Name of the camera manufacturer
Orientation of the image:
This information indicates the location of the point (0,0) in the image.
To display the image in the correct direction based on this information, use the following values:
- 1: the point (0,0) is at the top left, there is nothing to do.
- 2: the point (0,0) is at the top right, the image must be flipped horizontally.
- 3: the point (0,0) is at the bottom right, the image must be flipped horizontally and vertically.
- 4: the point (0,0) is at the bottom left, the image must be flipped horizontally.
- 5: the point (0,0) is at the top left, the image must be flipped horizontally and rotated 90°.
- 6: the point (0,0) is at the top right, the image must be rotated 90°.
- 7: the point (0,0) is at the bottom left, the image must be flipped vertically and rotated 90°.
- 8: the point (0,0) is at the bottom right, the image must be rotated -90°.
Aperture in APEX
Maximum aperture in APEX
Exposure mode used during the shot:
- 0: undefined.
- 1: manual.
- 2: normal.
- 3: priority to aperture.
- 4: priority to speed.
- 5: creation.
- 6: action.
- 7: portrait with no background.
- 8: landscape.
- 9 to 255: others.
Horizontal resolution of the image
Vertical resolution of the image
Light source for the image:
- 0: unknown.
- 1: daylight.
- 2: fluorescent.
- 3: tungsten.
- 17: standard light A.
- 18: standard light B.
- 19: standard light C.
- 20: D55.
- 21: D65.
- 22: D75.
- 23 to 254: reserved.
- 255: other.
Unit for the horizontal and vertical resolution of the image:
- 2: inches.
- 3: centimeters.
Version of Exif information
|65536||imgThumbnail||Binary string |
Thumbnail corresponding to the image
Shutter speed in APEX
Other tags are also available. These unlisted tags are specific to some types of cameras or correspond to custom tags.
returns no error code. To find out whether an error was generated by this function, use the ErrorOccurred
variable. To find out the error details, use ErrorInfo
Unit examples (WINDEV): The EXIF functions
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