| /*! \file exif-entry.h |
| * \brief Handling EXIF entries |
| */ |
| /* |
| * Copyright (c) 2001 Lutz Mueller <lutz@users.sourceforge.net> |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library 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 |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with this library; if not, write to the |
| * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| * Boston, MA 02110-1301 USA. |
| */ |
| |
| #ifndef __EXIF_ENTRY_H__ |
| #define __EXIF_ENTRY_H__ |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif /* __cplusplus */ |
| |
| /*! Data found in one EXIF tag. |
| * The #exif_entry_get_value function can provide access to the |
| * formatted contents, or the struct members can be used directly to |
| * access the raw contents. |
| */ |
| typedef struct _ExifEntry ExifEntry; |
| typedef struct _ExifEntryPrivate ExifEntryPrivate; |
| |
| #include <libexif/exif-content.h> |
| #include <libexif/exif-format.h> |
| #include <libexif/exif-mem.h> |
| |
| /*! Data found in one EXIF tag */ |
| struct _ExifEntry { |
| /*! EXIF tag for this entry */ |
| ExifTag tag; |
| |
| /*! Type of data in this entry */ |
| ExifFormat format; |
| |
| /*! Number of elements in the array, if this is an array entry. |
| * Contains 1 for non-array data types. */ |
| unsigned long components; |
| |
| /*! Pointer to the raw EXIF data for this entry. It is allocated |
| * by #exif_entry_initialize and is NULL beforehand. Data contained |
| * here may be manipulated using the functions in exif-utils.h */ |
| unsigned char *data; |
| |
| /*! Number of bytes in the buffer at \c data. This must be no less |
| * than exif_format_get_size(format)*components */ |
| unsigned int size; |
| |
| /*! #ExifContent containing this entry. |
| * \see exif_entry_get_ifd */ |
| ExifContent *parent; |
| |
| /*! Internal data to be used by libexif itself */ |
| ExifEntryPrivate *priv; |
| }; |
| |
| /* Lifecycle */ |
| |
| /*! Reserve memory for and initialize a new #ExifEntry. |
| * No memory is allocated for the \c data element of the returned #ExifEntry. |
| * |
| * \return new allocated #ExifEntry, or NULL on error |
| * |
| * \see exif_entry_new_mem, exif_entry_unref |
| */ |
| ExifEntry *exif_entry_new (void); |
| |
| /*! Reserve memory for and initialize new #ExifEntry using the specified |
| * memory allocator. |
| * No memory is allocated for the \c data element of the returned #ExifEntry. |
| * |
| * \return new allocated #ExifEntry, or NULL on error |
| * |
| * \see exif_entry_new, exif_entry_unref |
| */ |
| ExifEntry *exif_entry_new_mem (ExifMem *); |
| |
| /*! Increase reference counter for #ExifEntry. |
| * |
| * \param[in] entry #ExifEntry |
| * |
| * \see exif_entry_unref |
| */ |
| void exif_entry_ref (ExifEntry *entry); |
| |
| /*! Decrease reference counter for #ExifEntry. |
| * When the reference count drops to zero, free the entry. |
| * |
| * \param[in] entry #ExifEntry |
| */ |
| void exif_entry_unref (ExifEntry *entry); |
| |
| /*! Actually free the #ExifEntry. |
| * |
| * \deprecated Should not be called directly. Use #exif_entry_ref and |
| * #exif_entry_unref instead. |
| * |
| * \param[in] entry EXIF entry |
| */ |
| void exif_entry_free (ExifEntry *entry); |
| |
| /*! Initialize an empty #ExifEntry with default data in the correct format |
| * for the given tag. If the entry is already initialized, this function |
| * does nothing. |
| * This call allocates memory for the \c data element of the given #ExifEntry. |
| * That memory is freed at the same time as the #ExifEntry. |
| * |
| * \param[out] e entry to initialize |
| * \param[in] tag tag number to initialize as |
| */ |
| void exif_entry_initialize (ExifEntry *e, ExifTag tag); |
| |
| /*! Fix the type or format of the given EXIF entry to bring it into spec. |
| * If the data for this EXIF tag is in of the wrong type or is in an invalid |
| * format according to the EXIF specification, then it is converted to make it |
| * valid. This may involve, for example, converting an EXIF_FORMAT_LONG into a |
| * EXIF_FORMAT_SHORT. If the tag is unknown, its value is untouched. |
| * |
| * \note Unfortunately, some conversions are to a type with a more restricted |
| * range, which could have the side effect that the converted data becomes |
| * invalid. This is unlikely as the range of each tag in the standard is |
| * designed to encompass all likely data. |
| * |
| * \param[in,out] entry EXIF entry |
| */ |
| void exif_entry_fix (ExifEntry *entry); |
| |
| |
| /* For your convenience */ |
| |
| /*! Return a localized textual representation of the value of the EXIF entry. |
| * This is meant for display to the user. The format of each tag is subject |
| * to change between locales and in newer versions of libexif. Users who |
| * require the tag data in an unambiguous form should access the data members |
| * of the #ExifEntry structure directly. |
| * |
| * \warning The character set of the returned string may be in |
| * the encoding of the current locale or the native encoding |
| * of the camera. |
| * \bug The EXIF_TAG_XP_* tags are currently always returned in UTF-8, |
| * regardless of locale, and code points above U+FFFF are not |
| * supported. |
| * |
| * \param[in] entry EXIF entry |
| * \param[out] val buffer in which to store value |
| * \param[in] maxlen length of the buffer val |
| * \return val pointer |
| */ |
| const char *exif_entry_get_value (ExifEntry *entry, char *val, |
| unsigned int maxlen); |
| |
| /*! Dump text representation of #ExifEntry to stdout. |
| * This is intended for diagnostic purposes only. |
| * |
| * \param[in] entry EXIF tag data |
| * \param[in] indent how many levels deep to indent the data |
| */ |
| void exif_entry_dump (ExifEntry *entry, unsigned int indent); |
| |
| /*! Return the IFD number of the given #ExifEntry |
| * |
| * \param[in] e an #ExifEntry* |
| * \return #ExifIfd, or #EXIF_IFD_COUNT on error |
| */ |
| #define exif_entry_get_ifd(e) ((e)?exif_content_get_ifd((e)->parent):EXIF_IFD_COUNT) |
| |
| #ifdef __cplusplus |
| } |
| #endif /* __cplusplus */ |
| |
| #endif /* __EXIF_ENTRY_H__ */ |