I used
http://www.johnfindlay.plus.com/pellesc/GdiPlus.
to read and write exif part of jpg file.
reading exiftags is very easy with the examples given.
but writing? I tried to modify the existing GpPropertyTagImageDescription in the original image.jpg file
PROPERTYITEM buf;
char propValue[32] = "modified description";
buf.id = GpPropertyTagImageDescription;
buf.value = propValue;
if ( GpImage_SetPropertyItem(&image, &buf) == eOk)
{
MessageBox(NULL, "OK", "GpImage_SetPropertyItem", MB_OK);
.......
it is eOk. but the image.jpg does not change: still the original image.jpg file...
I tried to use
GP_IMAGE GpImage_FromFile(const WCHAR * filename, BOOL useEmbeddedColorManagement)
it succeeded, but once again, it gives a copy of the original image.jpg file unmodified.
I don't know how tomake it.
could I have some hint to do it?
many thanks.