Re: [gexiv2] Getting raw Exif, XMP or IPTC data

[Jim Nelson <jim yorba org>]

On Thu, Mar 27, 2014 at 12:07 PM, Christoph Hausner <christoph_hausner hotmail de> wrote:

thanks for your reply. There are static void Exiv2::ExifParser::encode, static int Exiv2::XmpParser::encode and static DataBuf Exiv2::IptcParser::encode. I have not verified yet if the representations they output are exactly the formats I need but the function descriptions sound promising.

Yes, I overlooked those.  They do seem promising, but more investigation would need to be done.  There's a lot of provisos in the documentation that make me wonder, in particular with the EXIF data being sized to fit inside a JPEG segment when it sounds like your plugin's not concerned with that.

One nice thing about gexiv2 is that is can smooth out the different interfaces' differences and return results in GObject-friendly containers.  For example, we could return a GByte object, or the caller could supply an GOutputStream.

In any event, if you're motivated to make this happen, I strongly encourage you to patch gexiv2 and submit it on bugzilla.  I would look at some of the other methods to see how the library is structured: the caller-facing method in gexiv2-metadata.cpp calling the format-specific method in gexiv2-metadata-<format>.cpp which then makes the C++ call into Exiv2.

-- Jim