gstreamer/ext/metadata/metadataexif.c
Edgard Lima d86770610e Convert from EXIF to XMP DataTime as local time.
Original commit message from CVS:
Convert from EXIF to XMP DataTime as local time.
2008-02-10 18:36:46 +00:00

1438 lines
39 KiB
C

/*
* GStreamer
* Copyright 2007 Edgard Lima <edgard.lima@indt.org.br>
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
* Alternatively, the contents of this file may be used under the
* GNU Lesser General Public License Version 2.1 (the "LGPL"), in
* which case the following provisions apply instead of the ones
* mentioned above:
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/*
* SECTION: metadataexif
* @short_description: This module provides functions to extract tags from
* EXIF metadata chunks and create EXIF chunks from metadata tags.
* @see_also: #metadatatags.[c/h]
*
* If libexif isn't available at compilation time, only the whole chunk
* (#METADATA_TAG_MAP_WHOLECHUNK) tags is created. It means that individual
* tags aren't mapped.
*
* Last reviewed on 2008-01-24 (0.10.15)
*/
/*
* includes
*/
#include "metadataexif.h"
#include "metadataparseutil.h"
#include "metadatatags.h"
/*
* defines
*/
GST_DEBUG_CATEGORY (gst_metadata_exif_debug);
#define GST_CAT_DEFAULT gst_metadata_exif_debug
/*
* Implementation when libexif isn't available at compilation time
*/
#ifndef HAVE_EXIF
/*
* extern functions implementations
*/
void
metadataparse_exif_tag_list_add (GstTagList * taglist, GstTagMergeMode mode,
GstAdapter * adapter, MetadataTagMapping mapping)
{
if (mapping & METADATA_TAG_MAP_WHOLECHUNK) {
GST_LOG ("EXIF not defined, sending just one tag as whole chunk");
metadataparse_util_tag_list_add_chunk (taglist, mode, GST_TAG_EXIF,
adapter);
}
}
void
metadatamux_exif_create_chunk_from_tag_list (guint8 ** buf, guint32 * size,
const GstTagList * taglist)
{
/* do nothing */
}
#else /* ifndef HAVE_EXIF */
/*
* Implementation when libexif is available at compilation time
*/
/*
* includes
*/
#include <libexif/exif-data.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <stdio.h>
/*
* enum and types
*/
typedef struct _tag_MEUserData
{
GstTagList *taglist;
GstTagMergeMode mode;
ExifShort resolution_unit; /* 2- inches (default), 3- cm */
int altitude_ref; /* -1- not specified, 0- above sea, 1- bellow sea */
gchar latitude_ref; /* k- not specified, 'N'- north, 'S'- south */
gchar longitude_ref; /* k- not specified, 'E'- north, 'W'- south */
} MEUserData;
typedef struct _tag_MapIntStr
{
ExifTag exif;
ExifIfd ifd;
const gchar *str;
} MapIntStr;
/*
* defines and static global vars
*/
/* *INDENT-OFF* */
/* When changing this table, update 'metadata_mapping.htm' file too. */
static MapIntStr mappedTags[] = {
{EXIF_TAG_APERTURE_VALUE, /*RATIONAL,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_APERTURE /*GST_TYPE_FRACTION*/},
{EXIF_TAG_BRIGHTNESS_VALUE, /*SRATIONAL,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_BRIGHTNESS /*GST_TYPE_FRACTION*/},
{EXIF_TAG_COLOR_SPACE, /*SHORT,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_COLOR_SPACE /*G_TYPE_UINT*/},
{EXIF_TAG_CONTRAST, /*SHORT,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_CONTRAST /*G_TYPE_INT*/},
{EXIF_TAG_CUSTOM_RENDERED, /*SHORT,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_CUSTOM_RENDERED /*G_TYPE_UINT*/},
{EXIF_TAG_DIGITAL_ZOOM_RATIO, /*RATIONAL,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_DIGITAL_ZOOM /*GST_TYPE_FRACTION*/},
{EXIF_TAG_EXPOSURE_PROGRAM, /*SHORT,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_EXPOSURE_PROGRAM /*G_TYPE_UINT*/},
{EXIF_TAG_EXPOSURE_MODE, /*SHORT,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_EXPOSURE_MODE /*G_TYPE_UINT*/},
{EXIF_TAG_EXPOSURE_TIME, /*RATIONAL,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_EXPOSURE_TIME /*GST_TYPE_FRACTION*/},
{EXIF_TAG_FLASH, /*SHORT*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_FLASH /*G_TYPE_UINT*/},
{EXIF_TAG_FNUMBER, /*RATIONAL,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_FNUMBER /*GST_TYPE_FRACTION*/},
{EXIF_TAG_FOCAL_LENGTH, /*SRATIONAL*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_FOCAL_LEN /*GST_TYPE_FRACTION*/},
{EXIF_TAG_GAIN_CONTROL, /*SHORT,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_GAIN /*G_TYPE_UINT*/},
{EXIF_TAG_ISO_SPEED_RATINGS, /*SHORT,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_ISO_SPEED_RATINGS /*G_TYPE_INT*/},
{EXIF_TAG_LIGHT_SOURCE, /*SHORT,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_LIGHT_SOURCE /*G_TYPE_UINT*/},
{EXIF_TAG_ORIENTATION, /*SHORT,*/ EXIF_IFD_0,
GST_TAG_CAPTURE_ORIENTATION /*G_TYPE_UINT*/},
{EXIF_TAG_SATURATION, /*SHORT,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_SATURATION /*G_TYPE_INT*/},
{EXIF_TAG_SCENE_CAPTURE_TYPE, /*SHORT,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_SCENE_CAPTURE_TYPE /*G_TYPE_UINT*/},
{EXIF_TAG_SHUTTER_SPEED_VALUE, /*SRATIONAL,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_SHUTTER_SPEED /*GST_TYPE_FRACTION*/},
{EXIF_TAG_WHITE_BALANCE, /*SHORT,*/ EXIF_IFD_EXIF,
GST_TAG_CAPTURE_WHITE_BALANCE /*G_TYPE_UINT*/},
{EXIF_TAG_SOFTWARE, /*ASCII,*/ EXIF_IFD_0,
GST_TAG_CREATOR_TOOL /*G_TYPE_STRING*/},
{EXIF_TAG_DATE_TIME_DIGITIZED, /*ASCII,*/ EXIF_IFD_EXIF,
GST_TAG_DATE_TIME_DIGITIZED /*G_TYPE_STRING*/},
{EXIF_TAG_DATE_TIME, /*ASCII,*/ EXIF_IFD_0,
GST_TAG_DATE_TIME_MODIFIED /*G_TYPE_STRING*/},
{EXIF_TAG_DATE_TIME_ORIGINAL, /*ASCII,*/ EXIF_IFD_EXIF,
GST_TAG_DATE_TIME_ORIGINAL /*G_TYPE_STRING*/},
{EXIF_TAG_MAKE, /*ASCII,*/ EXIF_IFD_0,
GST_TAG_DEVICE_MAKE /*G_TYPE_STRING*/},
{EXIF_TAG_MODEL, /*ASCII,*/ EXIF_IFD_0,
GST_TAG_DEVICE_MODEL /*G_TYPE_STRING*/},
{EXIF_TAG_MAKER_NOTE, /*UNDEFINED(size any)*/ EXIF_IFD_EXIF,
GST_TAG_EXIF_MAKER_NOTE /*GST_TYPE_BUFFER*/},
{EXIF_TAG_PIXEL_Y_DIMENSION, /*LONG,*/ EXIF_IFD_EXIF,
GST_TAG_IMAGE_HEIGHT /*G_TYPE_INT*/},
{EXIF_TAG_PIXEL_X_DIMENSION, /*LONG,*/ EXIF_IFD_EXIF,
GST_TAG_IMAGE_WIDTH /*G_TYPE_INT*/},
{EXIF_TAG_X_RESOLUTION, /*RATIONAL,*/ EXIF_IFD_0,
GST_TAG_IMAGE_XRESOLUTION /*GST_TYPE_FRACTION*/}, /* inches */
{EXIF_TAG_Y_RESOLUTION, /*RATIONAL,*/ EXIF_IFD_0,
GST_TAG_IMAGE_YRESOLUTION /*GST_TYPE_FRACTION*/}, /* inches */
{EXIF_TAG_GPS_ALTITUDE, /*RATIONAL,*/ EXIF_IFD_GPS,
GST_TAG_GPS_ALTITUDE /*GST_TYPE_FRACTION*/},
{EXIF_TAG_GPS_LATITUDE, /*RATIONAL(3),*/ EXIF_IFD_GPS,
GST_TAG_GPS_LATITUDE /*G_TYPE_STRING*/},
{EXIF_TAG_GPS_LONGITUDE, /*RATIONAL(3),*/ EXIF_IFD_GPS,
GST_TAG_GPS_LONGITUDE /*G_TYPE_STRING*/},
{0, EXIF_IFD_COUNT, NULL}
};
/* *INDENT-ON* */
#define IS_NUMBER(n) ('0' <= (n) && (n) <= '9')
#define IS_FRACT_POSITIVE(n,d) \
( ! ( ((n) >> (sizeof(n)*8-1)) ^ ((d) >> (sizeof(d)*8-1)) ) )
#define CHAR_TO_INT(c) ((c) - '0')
/*
* static helper functions declaration
*/
static const gchar *metadataparse_exif_get_tag_from_exif (ExifTag exif,
GType * type);
static ExifTag
metadatamux_exif_get_exif_from_tag (const gchar * tag, GType * type,
ExifIfd * ifd);
static void
metadataparse_exif_data_foreach_content_func (ExifContent * content,
void *callback_data);
static void
metadataparse_exif_content_foreach_entry_func (ExifEntry * entry,
void *user_data);
static gboolean
metadataparse_handle_unit_tags (ExifEntry * entry, MEUserData * meudata,
const ExifByteOrder byte_order);
static void
metadatamux_exif_for_each_tag_in_list (const GstTagList * list,
const gchar * tag, gpointer user_data);
static gboolean metadataparse_exif_convert_to_datetime (GString * dt);
static gboolean metadatamux_exif_convert_from_datetime (GString * dt);
static gboolean
metadatamux_exif_convert_from_gps (guint8 * data, const char *lt, char *ref);
static gboolean
metadataparse_exif_convert_to_gps (const guint8 * data, GString * lt,
const int exif_tag, const MEUserData * meudata);
/*
* extern functions implementations
*/
/*
* metadataparse_exif_tag_list_add:
* @taglist: tag list in which extracted tags will be added
* @mode: tag list merge mode
* @adapter: contains the EXIF metadata chunk
* @mapping: if is to extract individual tags and/or the whole chunk.
*
* This function gets a EXIF chunk (@adapter) and extract tags from it
* and the add to @taglist.
* Note: The EXIF chunk (@adapetr) must NOT be wrapped by any bytes specific
* to any file format
*
* Returns: nothing
*/
void
metadataparse_exif_tag_list_add (GstTagList * taglist, GstTagMergeMode mode,
GstAdapter * adapter, MetadataTagMapping mapping)
{
const guint8 *buf;
guint32 size;
ExifData *exif = NULL;
MEUserData user_data = { taglist, mode, 2, -1, 'k', 'k' };
if (adapter == NULL || (size = gst_adapter_available (adapter)) == 0) {
goto done;
}
/* add chunk tag */
if (mapping & METADATA_TAG_MAP_WHOLECHUNK)
metadataparse_util_tag_list_add_chunk (taglist, mode, GST_TAG_EXIF,
adapter);
if (!(mapping & METADATA_TAG_MAP_INDIVIDUALS))
goto done;
buf = gst_adapter_peek (adapter, size);
exif = exif_data_new_from_data (buf, size);
if (exif == NULL) {
goto done;
}
exif_data_foreach_content (exif,
metadataparse_exif_data_foreach_content_func, (void *) &user_data);
done:
if (exif)
exif_data_unref (exif);
return;
}
/*
* metadatamux_exif_create_chunk_from_tag_list:
* @buf: buffer that will have the created EXIF chunk
* @size: size of the buffer that will be created
* @taglist: list of tags to be added to EXIF chunk
*
* Get tags from @taglist, create a EXIF chunk based on it and save to @buf.
* Note: The EXIF chunk is NOT wrapped by any bytes specific to any file format
*
* Returns: nothing
*/
void
metadatamux_exif_create_chunk_from_tag_list (guint8 ** buf, guint32 * size,
const GstTagList * taglist)
{
ExifData *ed = NULL;
GstBuffer *exif_chunk = NULL;
const GValue *val = NULL;
if (!(buf && size))
goto done;
if (*buf) {
g_free (*buf);
*buf = NULL;
}
*size = 0;
val = gst_tag_list_get_value_index (taglist, GST_TAG_EXIF, 0);
if (val) {
exif_chunk = gst_value_get_buffer (val);
if (exif_chunk) {
ed = exif_data_new_from_data (GST_BUFFER_DATA (exif_chunk),
GST_BUFFER_SIZE (exif_chunk));
}
}
if (!ed) {
ed = exif_data_new ();
exif_data_set_data_type (ed, EXIF_DATA_TYPE_COMPRESSED);
exif_data_fix (ed);
}
gst_tag_list_foreach (taglist, metadatamux_exif_for_each_tag_in_list, ed);
exif_data_save_data (ed, buf, size);
done:
if (ed)
exif_data_unref (ed);
return;
}
/*
* static helper functions implementation
*/
/*
* metadataparse_exif_get_tag_from_exif:
* @exif: EXIF tag to look for
* @type: the type of the GStreamer tag mapped to @exif
*
* This returns the GStreamer tag mapped to an EXIF tag.
*
* Returns:
* <itemizedlist>
* <listitem><para>The GStreamer tag mapped to the @exif
* </para></listitem>
* <listitem><para>%NULL if there is no mapped GST tag for @exif
* </para></listitem>
* </itemizedlist>
*/
static const gchar *
metadataparse_exif_get_tag_from_exif (ExifTag exif, GType * type)
{
int i = 0;
while (mappedTags[i].exif) {
if (exif == mappedTags[i].exif) {
*type = gst_tag_get_type (mappedTags[i].str);
break;
}
++i;
}
return mappedTags[i].str;
}
/*
* metadatamux_exif_get_exif_from_tag:
* @tag: GST tag to look for
* @type: the type of the GStreamer @tag
* @ifd: the place into EXIF chunk @exif belongs to.
*
* This returns thet EXIF tag mapped to an GStreamer @tag.
*
* Returns:
* <itemizedlist>
* <listitem><para>The EXIF tag mapped to the GST @tag
* </para></listitem>
* <listitem><para>0 if there is no mapped EXIF tag for GST @tag
* </para></listitem>
* </itemizedlist>
*/
static ExifTag
metadatamux_exif_get_exif_from_tag (const gchar * tag, GType * type,
ExifIfd * ifd)
{
int i = 0;
while (mappedTags[i].exif) {
if (0 == strcmp (mappedTags[i].str, tag)) {
*type = gst_tag_get_type (tag);
*ifd = mappedTags[i].ifd;
break;
}
++i;
}
return mappedTags[i].exif;
}
/*
* metadataparse_exif_data_foreach_content_func:
* @content: EXIF structure from libexif containg a IFD
* @user_data: pointer to #MEUserData
*
* This function designed to be called for each EXIF IFD in a EXIF chunk. This
* function gets calls another function for each tag into @content. Then all
* tags into a EXIF chunk can be extracted to a tag list in @user_data.
* @see_also: #metadataparse_exif_tag_list_add
* #metadataparse_exif_content_foreach_entry_func
*
* Returns: nothing
*/
static void
metadataparse_exif_data_foreach_content_func (ExifContent * content,
void *user_data)
{
ExifIfd ifd = exif_content_get_ifd (content);
if (ifd == EXIF_IFD_0 || ifd == EXIF_IFD_EXIF || ifd == EXIF_IFD_GPS) {
GST_LOG ("\n Content %p: %s (ifd=%d)", content, exif_ifd_get_name (ifd),
ifd);
exif_content_foreach_entry (content,
metadataparse_exif_content_foreach_entry_func, user_data);
}
}
/*
* metadataparse_exif_content_foreach_entry_func:
* @entry: EXIF structure from libexif having a EXIF tag
* @user_data: pointer to #MEUserData
*
* This function designed to be called for each EXIF tag in a EXIF IFD. This
* function gets the EXIF tag from @entry and then add to the tag list
* in @user_data by using a merge mode also specified in @user_data
* @see_also: #metadataparse_exif_data_foreach_content_func
*
* Returns: nothing
*/
static void
metadataparse_exif_content_foreach_entry_func (ExifEntry * entry,
void *user_data)
{
char buf[2048];
MEUserData *meudata = (MEUserData *) user_data;
GType type = G_TYPE_NONE;
ExifByteOrder byte_order;
const gchar *tag = metadataparse_exif_get_tag_from_exif (entry->tag, &type);
/* We need the byte order */
if (!entry || !entry->parent || !entry->parent->parent)
return;
byte_order = exif_data_get_byte_order (entry->parent->parent);
if (metadataparse_handle_unit_tags (entry, meudata, byte_order))
goto done;
if (!tag)
goto done;
if (type == GST_TYPE_FRACTION) {
gint numerator = 0;
gint denominator = 1;
switch (entry->format) {
case EXIF_FORMAT_SRATIONAL:
{
ExifSRational v_srat;
v_srat = exif_get_srational (entry->data, byte_order);
if (v_srat.denominator) {
numerator = (gint) v_srat.numerator;
denominator = (gint) v_srat.denominator;
}
}
break;
case EXIF_FORMAT_RATIONAL:
{
ExifRational v_rat;
v_rat = exif_get_rational (entry->data, byte_order);
if (v_rat.denominator) {
numerator = (gint) v_rat.numerator;
denominator = (gint) v_rat.denominator;
}
if (meudata->altitude_ref == 1) {
if (entry->tag == EXIF_TAG_GPS_ALTITUDE) {
if (numerator > 0)
numerator = -numerator;
if (denominator < 0)
denominator = -denominator;
}
}
if (meudata->resolution_unit == 3) {
/* converts from cm to inches */
if (entry->tag == EXIF_TAG_X_RESOLUTION
|| entry->tag == EXIF_TAG_Y_RESOLUTION) {
numerator *= 2;
denominator *= 5;
}
}
}
break;
default:
GST_ERROR ("Unexpected Tag Type");
goto done;
break;
}
gst_tag_list_add (meudata->taglist, meudata->mode, tag, numerator,
denominator, NULL);
} else if (type == GST_TYPE_BUFFER) {
GstBuffer *buf = gst_buffer_new_and_alloc (entry->components);
memcpy (GST_BUFFER_DATA (buf), entry->data, entry->components);
gst_tag_list_add (meudata->taglist, meudata->mode, tag, buf, NULL);
gst_buffer_unref (buf);
} else {
switch (type) {
case G_TYPE_STRING:
{
const gchar *str = exif_entry_get_value (entry, buf, sizeof (buf));
GString *value = NULL;
if (entry->tag == EXIF_TAG_DATE_TIME_DIGITIZED
|| entry->tag == EXIF_TAG_DATE_TIME
|| entry->tag == EXIF_TAG_DATE_TIME_ORIGINAL) {
value = g_string_new_len (str, 20);
/* 20 is enough memory to hold "YYYY-MM-DDTHH:MM:SS" */
if (metadataparse_exif_convert_to_datetime (value)) {
str = value->str;
} else {
GST_ERROR ("Unexpected date & time format for %s", tag);
str = NULL;
}
} else if (entry->tag == EXIF_TAG_GPS_LATITUDE
|| entry->tag == EXIF_TAG_GPS_LONGITUDE) {
value = g_string_new_len (str, 11);
/* 21 is enough memory to hold "DDD:MM:SSk" */
if (metadataparse_exif_convert_to_gps (entry->data, value,
entry->tag, meudata)) {
str = value->str;
} else {
GST_ERROR ("Unexpected date & time format for %s", tag);
str = NULL;
}
}
if (str)
gst_tag_list_add (meudata->taglist, meudata->mode, tag, str, NULL);
if (value)
g_string_free (value, TRUE);
}
break;
case G_TYPE_INT:
/* fall through */
case G_TYPE_UINT:
{
gint value;
switch (entry->format) {
case EXIF_FORMAT_SHORT:
value = exif_get_short (entry->data, byte_order);
break;
case EXIF_FORMAT_LONG:
value = exif_get_long (entry->data, byte_order);
break;
default:
GST_ERROR ("Unexpected Exif Tag Type (%s - %s)",
tag, exif_format_get_name (entry->format));
goto done;
break;
}
if (entry->tag == EXIF_TAG_CONTRAST ||
entry->tag == EXIF_TAG_SATURATION) {
switch (value) {
case 0:
break;
case 1:
value = -67; /* -100-34 /2 */
break;
case 2:
value = 67; /* 100+34 /2 */
break;
default:
GST_ERROR ("Unexpected value");
break;
}
}
gst_tag_list_add (meudata->taglist, meudata->mode, tag, value, NULL);
}
break;
default:
break;
}
}
done:
GST_LOG ("\n Entry %p: %s (%s)\n"
" Size, Comps: %d, %d\n"
" Value: %s\n"
" Title: %s\n"
" Description: %s\n",
entry,
exif_tag_get_name (entry->tag),
exif_format_get_name (entry->format),
entry->size,
(int) (entry->components),
exif_entry_get_value (entry, buf, sizeof (buf)),
exif_tag_get_title (entry->tag), exif_tag_get_description (entry->tag));
return;
}
/*
* metadataparse_handle_unit_tags:
* @entry: The exif entry that is supposed to have a tag that makes reference
* to other tag
* @meudata: contains references that can be used afterwards and the tag list
* @byte_order: used to read Exif values
*
* This function tries to parse Exif tags that are not mapped to Gst tags
* but makes reference to another Exif-Gst mapped tag. For example,
* 'resolution-unit' that says the units of 'image-xresolution', so proper
* conversion is done or a hint to the conversion is stored to @meudata
* to be used afterwards.
*
* Returns:
* <itemizedlist>
* <listitem><para>%TRUE if the @entry->tag was handled
* </para></listitem>
* <listitem><para>%FALSE if this function does'n handle @entry->tag
* </para></listitem>
* </itemizedlist>
*/
static gboolean
metadataparse_handle_unit_tags (ExifEntry * entry, MEUserData * meudata,
const ExifByteOrder byte_order)
{
gboolean ret = TRUE;
switch (entry->tag) {
case EXIF_TAG_RESOLUTION_UNIT:
meudata->resolution_unit = exif_get_short (entry->data, byte_order);
if (meudata->resolution_unit == 3) {
/* if [xy]resolution has alredy been add in cm, replace it in inches */
gfloat value;
if (gst_tag_list_get_float (meudata->taglist,
GST_TAG_IMAGE_XRESOLUTION, &value)) {
gst_tag_list_add (meudata->taglist, GST_TAG_MERGE_REPLACE,
GST_TAG_IMAGE_XRESOLUTION, value * 0.4f, NULL);
}
if (gst_tag_list_get_float (meudata->taglist,
GST_TAG_IMAGE_YRESOLUTION, &value)) {
gst_tag_list_add (meudata->taglist, GST_TAG_MERGE_REPLACE,
GST_TAG_IMAGE_YRESOLUTION, value * 0.4f, NULL);
}
}
break;
case EXIF_TAG_GPS_ALTITUDE_REF:
meudata->altitude_ref = entry->data[0];
const GValue *value = gst_tag_list_get_value_index (meudata->taglist,
GST_TAG_GPS_ALTITUDE, 0);
if (value) {
gint n, d;
n = gst_value_get_fraction_numerator (value);
d = gst_value_get_fraction_denominator (value);
if (meudata->altitude_ref == 1) { /* bellow sea */
if (IS_FRACT_POSITIVE (n, d)) { /* if n * d > 0 */
gst_tag_list_add (meudata->taglist, GST_TAG_MERGE_REPLACE,
GST_TAG_GPS_ALTITUDE, -n, d, NULL);
}
}
}
break;
case EXIF_TAG_GPS_LATITUDE_REF:
{
gchar *value = NULL;
meudata->latitude_ref = entry->data[0];
if (gst_tag_list_get_string (meudata->taglist, GST_TAG_GPS_LATITUDE,
&value)) {
GString *str = g_string_new (value);
if (str->len == 10) {
str->str[9] = meudata->latitude_ref;
gst_tag_list_add (meudata->taglist, GST_TAG_MERGE_REPLACE,
GST_TAG_GPS_LATITUDE, str->str, NULL);
}
g_string_free (str, TRUE);
}
}
break;
case EXIF_TAG_GPS_LONGITUDE_REF:
{
gchar *value = NULL;
meudata->longitude_ref = entry->data[0];
if (gst_tag_list_get_string (meudata->taglist, GST_TAG_GPS_LONGITUDE,
&value)) {
GString *str = g_string_new (value);
if (str->len == 10) {
str->str[9] = meudata->longitude_ref;
gst_tag_list_add (meudata->taglist, GST_TAG_MERGE_REPLACE,
GST_TAG_GPS_LONGITUDE, str->str, NULL);
}
g_string_free (str, TRUE);
}
}
break;
default:
ret = FALSE;
break;
}
return ret;
}
/*
* metadatamux_exif_for_each_tag_in_list:
* @list: GStreamer tag list from which @tag belongs to
* @tag: GStreamer tag to be added to the EXIF chunk
* @user_data: pointer to #ExifData in which the tag will be added
*
* This function designed to be called for each tag in GST tag list. This
* function adds get the tag value from tag @list and then add it to the EXIF
* chunk by using #ExifData and related functions from libexif
* @see_also: #metadatamux_exif_create_chunk_from_tag_list
*
* Returns: nothing
*/
static void
metadatamux_exif_for_each_tag_in_list (const GstTagList * list,
const gchar * tag, gpointer user_data)
{
ExifData *ed = (ExifData *) user_data;
ExifTag exif_tag;
GType type;
ExifEntry *entry = NULL;
ExifIfd ifd;
const ExifByteOrder byte_order = exif_data_get_byte_order (ed);
exif_tag = metadatamux_exif_get_exif_from_tag (tag, &type, &ifd);
if (!exif_tag)
goto done;
entry = exif_data_get_entry (ed, exif_tag);
if (entry)
exif_entry_ref (entry);
else {
entry = exif_entry_new ();
exif_content_add_entry (ed->ifd[ifd], entry);
exif_entry_initialize (entry, exif_tag);
}
if (entry->data == NULL) {
if (entry->tag == EXIF_TAG_GPS_ALTITUDE) {
entry->format = EXIF_FORMAT_RATIONAL;
entry->components = 1;
entry->size = exif_format_get_size (entry->format) * entry->components;
entry->data = g_malloc (entry->size);
} else if (entry->tag == EXIF_TAG_GPS_LATITUDE
|| entry->tag == EXIF_TAG_GPS_LONGITUDE) {
entry->format = EXIF_FORMAT_RATIONAL;
entry->components = 3;
entry->size = exif_format_get_size (entry->format) * entry->components;
entry->data = g_malloc (entry->size);
}
}
if (type == GST_TYPE_FRACTION) {
const GValue *gvalue = gst_tag_list_get_value_index (list, tag, 0);
gint numerator = gst_value_get_fraction_numerator (gvalue);
gint denominator = gst_value_get_fraction_denominator (gvalue);
switch (entry->format) {
case EXIF_FORMAT_SRATIONAL:
{
ExifSRational sr = { numerator, denominator };
exif_set_srational (entry->data, byte_order, sr);
}
break;
case EXIF_FORMAT_RATIONAL:
{
ExifRational r;
if (entry->tag == EXIF_TAG_GPS_ALTITUDE) {
ExifEntry *ref_entry = NULL;
ref_entry = exif_data_get_entry (ed, EXIF_TAG_GPS_ALTITUDE_REF);
if (ref_entry) {
exif_entry_ref (ref_entry);
} else {
ref_entry = exif_entry_new ();
exif_content_add_entry (ed->ifd[EXIF_IFD_GPS], ref_entry);
exif_entry_initialize (ref_entry, EXIF_TAG_GPS_ALTITUDE_REF);
}
if (ref_entry->data == NULL) {
ref_entry->format = EXIF_FORMAT_BYTE;
ref_entry->components = 1;
ref_entry->size = 1;
ref_entry->data = g_malloc (1);
}
/* if n * d > 0 */
if (IS_FRACT_POSITIVE (numerator, denominator)) {
ref_entry->data[0] = 0;
} else {
ref_entry->data[0] = 1;
}
exif_entry_unref (ref_entry);
}
if (entry->tag == EXIF_TAG_X_RESOLUTION ||
entry->tag == EXIF_TAG_Y_RESOLUTION) {
ExifEntry *unit_entry = NULL;
unit_entry = exif_data_get_entry (ed, EXIF_TAG_RESOLUTION_UNIT);
if (unit_entry) {
ExifShort vsh = exif_get_short (unit_entry->data, byte_order);
if (vsh != 2) /* inches */
exif_set_short (unit_entry->data, byte_order, 2);
}
}
r.numerator = numerator;
r.denominator = denominator;
if (numerator < 0)
r.numerator = -numerator;
if (denominator < 0)
r.denominator = -denominator;
exif_set_rational (entry->data, byte_order, r);
}
break;
default:
break;
}
} else if (type == GST_TYPE_BUFFER) {
const GValue *val = NULL;
GstBuffer *buf;
val = gst_tag_list_get_value_index (list, tag, 0);
buf = gst_value_get_buffer (val);
entry->components = GST_BUFFER_SIZE (buf);
entry->size = GST_BUFFER_SIZE (buf);
entry->data = g_malloc (entry->size);
memcpy (entry->data, GST_BUFFER_DATA (buf), entry->size);
} else {
switch (type) {
case G_TYPE_STRING:
{
gchar *value = NULL;
if (gst_tag_list_get_string (list, tag, &value)) {
if (entry->tag == EXIF_TAG_DATE_TIME_DIGITIZED
|| entry->tag == EXIF_TAG_DATE_TIME
|| entry->tag == EXIF_TAG_DATE_TIME_ORIGINAL) {
GString *datetime = g_string_new_len (value,
20); /* enough memory to hold "YYYY:MM:DD HH:MM:SS" */
if (metadatamux_exif_convert_from_datetime (datetime)) {
} else {
GST_ERROR ("Unexpected date & time format for %s", tag);
}
g_free (value);
value = datetime->str;
g_string_free (datetime, FALSE);
} else if (entry->tag == EXIF_TAG_GPS_LATITUDE
|| entry->tag == EXIF_TAG_GPS_LONGITUDE) {
char ref;
if (metadatamux_exif_convert_from_gps (entry->data, value, &ref)) {
ExifEntry *ref_entry = NULL;
const ExifTag ref_tag = entry->tag == EXIF_TAG_GPS_LATITUDE ?
EXIF_TAG_GPS_LATITUDE_REF : EXIF_TAG_GPS_LONGITUDE_REF;
ref_entry = exif_data_get_entry (ed, ref_tag);
if (ref_entry) {
exif_entry_ref (ref_entry);
} else {
ref_entry = exif_entry_new ();
exif_content_add_entry (ed->ifd[EXIF_IFD_GPS], ref_entry);
exif_entry_initialize (ref_entry, ref_tag);
}
if (ref_entry->data == NULL) {
ref_entry->format = EXIF_FORMAT_ASCII;
ref_entry->components = 2;
ref_entry->size = 2;
ref_entry->data = g_malloc (2);
}
ref_entry->data[0] = ref;
ref_entry->data[1] = 0;
exif_entry_unref (ref_entry);
}
/* has already been add and it is not an Exif ASCII type */
g_free (value);
value = NULL;
}
if (value) {
entry->components = strlen (value) + 1;
entry->size =
exif_format_get_size (entry->format) * entry->components;
entry->data = (guint8 *) value;
value = NULL;
}
}
}
break;
case G_TYPE_UINT:
case G_TYPE_INT:
{
gint value;
ExifShort v_short;
if (G_TYPE_UINT == type) {
gst_tag_list_get_uint (list, tag, (guint *) & value);
} else {
gst_tag_list_get_int (list, tag, &value);
}
switch (entry->format) {
case EXIF_FORMAT_SHORT:
if (entry->tag == EXIF_TAG_CONTRAST
|| entry->tag == EXIF_TAG_SATURATION) {
if (value < -33)
value = 1; /* low */
else if (value < 34)
value = 0; /* normal */
else
value = 2; /* high */
}
v_short = value;
exif_set_short (entry->data, byte_order, v_short);
break;
case EXIF_FORMAT_LONG:
exif_set_long (entry->data, byte_order, value);
break;
default:
break;
}
}
break;
default:
break;
}
}
done:
if (entry)
exif_entry_unref (entry);
}
/*
* metadataparse_exif_convert_to_datetime:
* @dt: string containing date_time in format "YYYY:MM:DD HH:MM:SS"
*
* This function converts a exif date_and_time string @dt into the format
* specified by http://www.w3.org/TR/1998/NOTE-datetime-19980827, in which a
* subset of ISO RFC 8601 used by XMP.
* @dt->allocated_len must be not less than 21 to hold enough memory
* hold "YYYY:MM:DD HH:MM:SS" without additional allocation
*
* Returns:
* <itemizedlist>
* <listitem><para>#TRUE if succeded
* </para></listitem>
* <listitem><para>#FALSE if failed
* </para></listitem>
* </itemizedlist>
*/
static gboolean
metadataparse_exif_convert_to_datetime (GString * dt)
{
/* "YYYY:MM:DD HH:MM:SS" */
/* 012345678901234567890 */
if (dt->allocated_len < 20)
return FALSE;
/* Fix me: Ideally would be good to get the time zone from othe Exif tag
* for the time being, just use local time as explained in XMP specification
* (converting from EXIF to XMP date and time) */
dt->str[4] = '-';
dt->str[7] = '-';
dt->str[10] = 'T';
dt->str[19] = '\0';
return TRUE;
}
/*
* metadatamux_exif_convert_from_datetime:
* @dt: string containing date_time in format specified by
* http://www.w3.org/TR/1998/NOTE-datetime-19980827
*
* This function converts a date_and_time string @dt as specified by
* http://www.w3.org/TR/1998/NOTE-datetime-19980827, in which a
* subset of ISO RFC 8601 used by XMP, into Exif date_time format.
* @dt->allocated_len must be not less than 20 to hold enough memory
* hold "YYYY:MM:DD HH:MM:SS" without additional allocation
*
* Returns:
* <itemizedlist>
* <listitem><para>#TRUE if succeded
* </para></listitem>
* <listitem><para>#FALSE if failed
* </para></listitem>
* </itemizedlist>
*/
static gboolean
metadatamux_exif_convert_from_datetime (GString * dt)
{
gboolean ret = TRUE;
char *p = dt->str;
if (dt->allocated_len < 20)
goto error;
/* check YYYY */
if (IS_NUMBER (*p))
p++;
else
goto error;
if (IS_NUMBER (*p))
p++;
else
goto error;
if (IS_NUMBER (*p))
p++;
else
goto error;
if (IS_NUMBER (*p))
p++;
else
goto error;
if (*p == '\0') {
sprintf (p, ":01:01 00:00:00");
goto done;
} else if (*p == '-') {
*p++ = ':';
} else
goto error;
/* check MM */
if (IS_NUMBER (*p))
p++;
else
goto error;
if (IS_NUMBER (*p))
p++;
else
goto error;
if (*p == '\0') {
sprintf (p, ":01 00:00:00");
goto done;
} else if (*p == '-') {
*p++ = ':';
} else
goto error;
/* check DD */
if (IS_NUMBER (*p))
p++;
else
goto error;
if (IS_NUMBER (*p))
p++;
else
goto error;
if (*p == '\0') {
sprintf (p, " 00:00:00");
goto done;
} else if (*p == 'T') {
*p++ = ' ';
} else
goto error;
/* check hh */
if (IS_NUMBER (*p))
p++;
else
goto error;
if (IS_NUMBER (*p))
p++;
else
goto error;
if (*p++ != ':')
goto error;
/* check mm */
if (IS_NUMBER (*p))
p++;
else
goto error;
if (IS_NUMBER (*p))
p++;
else
goto error;
if (*p == ':') {
p++;
} else if (*p == 'Z' || *p == '+' || *p == '-') {
/* FIXME: in case of '+' or '-', it would be better to also fill another
* EXIF tag in order to save, somehow the time zone info */
sprintf (p, ":00");
goto done;
} else
goto error;
/* check ss */
if (IS_NUMBER (*p))
p++;
else
goto error;
if (IS_NUMBER (*p))
p++;
else
goto error;
*p = '\0';
/* if here, everything is ok */
goto done;
error:
ret = FALSE;
done:
/* FIXME: do we need to check if the date is valid ? */
if (ret)
dt->len = 19;
return ret;
}
/*
* metadatamux_exif_convert_from_gps:
* @data: pointer to an array of 3 ExifRational in which gps will be stored
* @lt: a string containing the gps coordinate formated as "DDD,MM,SSk"
* or "DDD,MM.mmk" (this is the same as specified in XMP).
* @ref: at the end will store the reference ('N', 'S', 'E', 'W')
*
* This function converts from the format "DDD,MM,SSk" or "DDD,MM.mmk"
* (the same as specified in XMP) into Exif coordinates.
* D- degrees, M- minutes, S- seconds, k- 'N', 'S', 'E', 'W'
* (North, South, East, West)
*
* Returns:
* <itemizedlist>
* <listitem><para>%TRUE if converted sucessfull
* </para></listitem>
* <listitem><para>%FALSE if @lt is bad formated
* </para></listitem>
* </itemizedlist>
*/
static gboolean
metadatamux_exif_convert_from_gps (guint8 * data, const char *lt, char *ref)
{
/* "DDD,MM,SSk" or "DDD,MM.mmk" */
/* 0123456789 0123456789 */
gboolean ret = TRUE;
char *p = (char *) lt;
ExifRational *rt = (ExifRational *) data;
if (strlen (lt) != 10)
goto error;
if (lt[6] == ',' || lt[6] == '.') {
if (IS_NUMBER (*p) && IS_NUMBER (*(p + 1)) && IS_NUMBER (*(p + 2))) {
rt->numerator = CHAR_TO_INT (*p) * 100;
p++;
rt->numerator += CHAR_TO_INT (*p) * 10;
p++;
rt->numerator += CHAR_TO_INT (*p);
p++;
rt->denominator = 1;
} else {
goto error;
}
p++;
rt++;
if (IS_NUMBER (*p) && IS_NUMBER (*(p + 1))) {
rt->numerator = CHAR_TO_INT (*p) * 10;
p++;
rt->numerator += CHAR_TO_INT (*p);
p++;
rt->denominator = 1;
} else {
goto error;
}
p++;
rt++;
if (IS_NUMBER (*p) && IS_NUMBER (*(p + 1))) {
rt->numerator = CHAR_TO_INT (*p) * 10;
p++;
rt->numerator += CHAR_TO_INT (*p);
p++;
rt->denominator = 1;
} else {
goto error;
}
} else {
goto error;
}
if (lt[9] != 'N' && lt[9] != 'S' && lt[9] != 'E' && lt[9] != 'W')
goto error;
*ref = lt[9];
goto done;
error:
ret = FALSE;
done:
return ret;
}
/*
* metadatamux_exif_convert_from_gps:
* @data: pointer to an array of 3 ExifRational from which gps will be read
* @lt: at the end this will have the gps coordinate formated as "DDD,MM,SSk"
* or "DDD,MM.mmk" (this is the same as specified in XMP).
* @exif_tag: EXIF_TAG_GPS_LATITUDE or EXIF_TAG_GPS_LONGITUDE
* @meudata: at the end will store the reference ('N', 'S', 'E', 'W')
* in @meudata->latitude_ref or meudata->longitude_ref depending on @exif_tag
*
* This function converts from Exif coordinates to the format "DDD,MM,SSk"
* or "DDD,MM.mmk" (the same as specified in XMP).
* D- degrees, M- minutes, S- seconds, k- 'N', 'S', 'E', 'W'
* (North, South, East, West)
* Precondition: @lt->allocated_len must be at least 11.
*
* Returns:
* <itemizedlist>
* <listitem><para>%TRUE if converted sucessfull
* </para></listitem>
* <listitem><para>%FALSE if error
* </para></listitem>
* </itemizedlist>
*/
static gboolean
metadataparse_exif_convert_to_gps (const guint8 * data, GString * lt,
const int exif_tag, const MEUserData * meudata)
{
ExifRational *rt = (ExifRational *) data;
char *str = lt->str;
gboolean ret = TRUE;
char ref;
if (lt->allocated_len < 11)
goto error;
if (exif_tag == EXIF_TAG_GPS_LATITUDE)
ref = meudata->latitude_ref;
else if (exif_tag == EXIF_TAG_GPS_LONGITUDE)
ref = meudata->longitude_ref;
else
goto error;
/* DDD - degrees */
sprintf (str, "%03u,", rt->numerator / rt->denominator);
rt++;
str += 4;
/* MM - minutes and SS - seconds */
if (rt->numerator % rt->denominator) {
sprintf (str, "%05.02f", (float) rt->numerator / (float) rt->denominator);
str += 5;
*str++ = ref;
*str = '\0';
} else {
sprintf (str, "%02u,", rt->numerator / rt->denominator);
str += 3;
rt++;
sprintf (str, "%02u", rt->numerator / rt->denominator);
str += 2;
*str++ = ref;
*str = '\0';
}
/* if here, everything is ok */
goto done;
error:
ret = FALSE;
done:
/* FIXME: do we need to check if the date is valid ? */
if (ret)
lt->len = 10;
return ret;
}
#endif /* else (ifndef HAVE_EXIF) */