Horizontal resolution. 0x011A ∙ 282
IG_ISIS_TAG_XRESOLUTION specifies or indicates the number of pixels per IG_ISIS_TAG_RESUNIT (which for ISIS scanning is always pixels per inch).
Type:
IG_ISIS_TAG_TYPE_RATIONAL
Drivers:
All source and destination drivers.
Values:
A rational value specifying the horizontal resolution in pixels per inch.
Tag Dependencies and Dependent Tags:
IG_ISIS_TAG_PAGESIZE ∙ IG_ISIS_TAG_XRESOLUTION ∙ IG_ISIS_TAG_YRESOLUTION ∙ IG_ISIS_TAG_XPOSITION ∙ IG_ISIS_TAG_YPOSITION ∙ IG_ISIS_TAG_IMAGEWIDTH ∙ IG_ISIS_TAG_IMAGELENGTH
Note that setting IG_ISIS_TAG_XRESOLUTION sets IG_ISIS_TAG_YRESOLUTION to the same value. If you want to set independent resolutions, you must set IG_ISIS_TAG_YRESOLUTION after setting IG_ISIS_TAG_XRESOLUTION.
Remarks:
IG_ISIS_TAG_XRESOLUTION is used to specify the horizontal (and usually the vertical) resolution. When scanning, this controls the scanner's resolution. Query the choices for IG_ISIS_TAG_XRESOLUTION to determine the available settings. To find out whether or not the scanner supports independent X and Y resolutions, query the choices for IG_ISIS_TAG_YRESOLUTION. If there is only one choice, and it matches the value set for IG_ISIS_TAG_XRESOLUTION, then the scanner does not support independent resolutions.
When reading an image, IG_ISIS_TAG_XRESOLUTION, if present, indicates the value of the Resolution tag that has been saved in the file.