subsurface/core/xmp_parser.h

// Parse XMP blocks using libxml2

#ifndef XMP_PARSER_H
#define XMP_PARSER_H

#include "units.h" // for timestamp_t
#include <stddef.h> // for size_t

timestamp_t parse_xmp(const char *data, size_t size); // On failure returns 0.

#endif // XMP_PARSER_H
Metadata: rudimentary support for XMP metadataa in MP4-based videos XMP is a media-metadata standard based on XML which may be used across a variety of media formats. Some video-processing software writes XMP data without updating the native metadata fields. Therefore, we should aim at reading XMP metadata and give priority of XMP data over native fields. Pros: - Support for all common media formats. Cons: - XML (complex, verbose, chaotic). - Does not even come close to fulfilling its promise of being well defined (see below). Implement a simple XMP-parser using libxml2. Connect the XMP-parser to the existing Quicktime/MP4 parser. First problem encountered: According to the spec, XMP data supposed to be put in the 'XMP_' atom. But for example exiftools instead writes an 'uuid' atom with a special 16-byte uid. Implement both, more options will probably follow. Second problem: two versions of recording the creation date were found 1) The content of a <exif:DateTimeOriginal> tag. 2) The xmp::CreateDate attribute of a <rdf:Description> tag. Here too, more versions are expected to surface and will have to be supported in due course (with an obvious priority problem). Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at> 2018-09-15 17:11:01 +00:00			`// Parse XMP blocks using libxml2`

			`#ifndef XMP_PARSER_H`
			`#define XMP_PARSER_H`

			`#include "units.h" // for timestamp_t`
			`#include <stddef.h> // for size_t`

			`timestamp_t parse_xmp(const char *data, size_t size); // On failure returns 0.`

			`#endif // XMP_PARSER_H`