Image Property Tag Constant

Question

I'd like to use the image property tag constants defined in GDI+ from .NET.

I wonder whether these constant values (e.g. PropertyTagGpsVer constant) are exposed in any of the Base Class Library?

I have tried looking around System.Drawing.Imaging namespace to no avail.

Answer 1

You're looking for the System.Drawing.Imaging.PropertyItem class. See a description and an example on MSDN

Answer 2

No, they are not.

Enumeration of the tags: http://msdn.microsoft.com/en-us/library/ms534417%28VS.85%29.aspx Long description of the tags: http://msdn.microsoft.com/en-us/library/ms534416%28VS.85%29.aspx

I ended up copying and pasting most of these two pages into code in order to do what you want: have a set of constants. You'll need to implement a set of PropertyItems by name and pre-populate them with the id, length, and type of the PropertyItem.

The other way to do it is t just choose the constants you need and implement them.

Answer 3

Here is a complete example of the kind of code you want to use: Code Sample

i tested it, it compiled ran and here's an example of the data it returned (ugly but proves the concept.)

RESULT:

Image: \Desktop\SouthSisterPanorama.jpg
Width= 5861, Height= 625
PixelFormat = Format24bppRgb
Dumping 2 property items:PropertyTagLuminanceTable 
 Type:PropertyTagTypeShort
 Length:128
 Values:
 08 00 06 00 05 00 08 00 0C 00 14 00 1A 00 1F 00  ................
 06 00 06 00 07 00 0A 00 0D 00 1D 00 1E 00 1C 00  ................
 07 00 07 00 08 00 0C 00 14 00 1D 00 23 00 1C 00  ............#...
 07 00 09 00 0B 00 0F 00 1A 00 2C 00 28 00 1F 00  ..........,.(...
 09 00 0B 00 13 00 1C 00 22 00 37 00 34 00 27 00  ........".7.4.'.
 0C 00 12 00 1C 00 20 00 29 00 34 00 39 00 2E 00  ...... .).4.9...
 19 00 20 00 27 00 2C 00 34 00 3D 00 3C 00 33 00  .. .'.,.4.=.<.3.
 24 00 2E 00 30 00 31 00 38 00 32 00 34 00 32 00  $...0.1.8.2.4.2.

PropertyTagChrominanceTable 
 Type:PropertyTagTypeShort
 Length:128
 Values:
 09 00 09 00 0C 00 18 00 32 00 32 00 32 00 32 00  ........2.2.2.2.
 09 00 0B 00 0D 00 21 00 32 00 32 00 32 00 32 00  ......!.2.2.2.2.
 0C 00 0D 00 1C 00 32 00 32 00 32 00 32 00 32 00  ......2.2.2.2.2.
 18 00 21 00 32 00 32 00 32 00 32 00 32 00 32 00  ..!.2.2.2.2.2.2.
 32 00 32 00 32 00 32 00 32 00 32 00 32 00 32 00  2.2.2.2.2.2.2.2.
 32 00 32 00 32 00 32 00 32 00 32 00 32 00 32 00  2.2.2.2.2.2.2.2.
 32 00 32 00 32 00 32 00 32 00 32 00 32 00 32 00  2.2.2.2.2.2.2.2.
 32 00 32 00 32 00 32 00 32 00 32 00 32 00 32 00  2.2.2.2.2.2.2.2.

Answer 4

If you have the Microsoft SDKs, you can find all the constants in a C header file named GdiPlusImaging.h

It would be simple enough to include the header in a C project, but you'd have to do some tweaking to put them all into enumerations.