blender-archive/source/blender/imbuf/IMB_metadata.h

/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2005 Blender Foundation
 * All rights reserved.
 */

/** \file
 * \ingroup imbuf
 */


#ifndef __IMB_METADATA_H__
#define __IMB_METADATA_H__

struct IDProperty;
struct ImBuf;
struct anim;

/** The metadata is a list of key/value pairs (both char *) that can me
 * saved in the header of several image formats.
 * Apart from some common keys like
 * 'Software' and 'Description' (png standard) we'll use keys within the
 * Blender namespace, so should be called 'Blender::StampInfo' or 'Blender::FrameNum'
 * etc...
 *
 * The keys & values are stored in ID properties, in the group "metadata".
 */

/** Ensure that the metadata property is a valid IDProperty object.
 * This is a no-op when *metadata != NULL.
 */
void IMB_metadata_ensure(struct IDProperty **metadata);
void IMB_metadata_free(struct IDProperty *metadata);

/** Read the field from the image info into the field.
 * \param metadata: the IDProperty that contains the metadata
 * \param key: the key of the field
 * \param value: the data in the field, first one found with key is returned,
 *                 memory has to be allocated by user.
 * \param len: length of value buffer allocated by user.
 * \return    - 1 (true) if metadata is present and value for the key found, 0 (false) otherwise
 */
bool IMB_metadata_get_field(struct IDProperty *metadata, const char *key, char *value, const size_t len);

/** Set user data in the metadata.
 * If the field already exists its value is overwritten, otherwise the field
 * will be added with the given value.
 * \param metadata: the IDProperty that contains the metadata
 * \param key: the key of the field
 * \param value: the data to be written to the field. zero terminated string
 */
void IMB_metadata_set_field(struct IDProperty *metadata, const char *key, const char *value);

void IMB_metadata_copy(struct ImBuf *dimb, struct ImBuf *simb);
struct IDProperty *IMB_anim_load_metadata(struct anim *anim);

/* Invoke callback for every value stored in the metadata. */
typedef void (*IMBMetadataForeachCb)(const char *field, const char *value, void *userdata);
void IMB_metadata_foreach(struct ImBuf *ibuf, IMBMetadataForeachCb callback, void *userdata);

#endif /* __IMB_METADATA_H__ */