std::string Exif::value(std::string tag_name) const {
ExifEntry *entry;
ExifTag tag;
std::string value;
char raw_value[1024];
tag = exif_tag_from_name(tag_name.c_str());
entry = exif_data_get_entry(m_data, tag);
value = exif_entry_get_value(entry, raw_value, sizeof(raw_value));
return value;
}
static void *
vips_exif_image_field( VipsImage *image,
const char *field, GValue *value, void *data )
{
ExifData *ed = (ExifData *) data;
const char *string;
int ifd;
const char *p;
ExifTag tag;
if( !vips_isprefix( "exif-ifd", field ) )
return( NULL );
/* value must be a string.
*/
if( vips_image_get_string( image, field, &string ) ) {
g_warning( _( "bad exif meta \"%s\"" ), field );
return( NULL );
}
p = field + strlen( "exif-ifd" );
ifd = atoi( p );
for( ; isdigit( *p ); p++ )
;
if( *p != '-' ) {
g_warning( _( "bad exif meta \"%s\"" ), field );
return( NULL );
}
if( !(tag = exif_tag_from_name( p + 1 )) ) {
g_warning( _( "bad exif meta \"%s\"" ), field );
return( NULL );
}
vips_exif_set_tag( ed, ifd, tag, vips_exif_set_entry, (void *) string );
return( NULL );
}
static int iExifWriteTag(ExifData* exif, int index, const char* name, int data_type, int attrib_count, const void* attrib_data)
{
int c;
ExifTag tag = exif_tag_from_name(name);
if (tag == 0)
{
if (!imStrEqual(name, "GPSVersionID")) // EXIF_TAG_GPS_VERSION_ID==0
return 1;
}
ExifEntry *entry = exif_entry_new();
ExifByteOrder byte_order = exif_data_get_byte_order(exif);
ExifContent *content;
if (name[0] == 'G' && name[1] == 'P' && name[2] == 'S')
{
content = exif->ifd[EXIF_IFD_GPS]; // GPS tags
if (!iExifGetGPSTagInfo((int)tag, &(entry->format), &(entry->components)))
{
exif_entry_free(entry);
return 1;
}
}
else
{
if (tag > EXIF_TAG_COPYRIGHT)
content = exif->ifd[EXIF_IFD_EXIF]; // EXIF tags
else
content = exif->ifd[EXIF_IFD_0]; // TIFF tags
if (!iExifGetTagInfo(tag, &(entry->format), &(entry->components)))
{
exif_entry_free(entry);
return 1;
}
}
int format_size = exif_format_get_size(entry->format);
if (entry->components == 0)
entry->components = attrib_count;
entry->tag = tag;
entry->size = format_size * entry->components;
entry->data = (imbyte*)malloc(entry->size);
if (tag == EXIF_TAG_RESOLUTION_UNIT)
{
int res_unit;
if (imStrEqual((char*)attrib_data, "DPI"))
res_unit = 2;
else
res_unit = 3;
exif_content_add_entry(content, entry);
exif_set_short(entry->data, byte_order, (imushort)res_unit);
return 1;
}
/* test if tag type is the same as the attribute type */
if (iExifGetDataType(entry->format) != data_type)
{
exif_entry_free(entry);
return 1;
}
exif_content_add_entry(content, entry);
switch (entry->format)
{
case EXIF_FORMAT_UNDEFINED:
case EXIF_FORMAT_ASCII:
case EXIF_FORMAT_SBYTE:
case EXIF_FORMAT_BYTE:
{
imbyte *bvalue = (imbyte*)attrib_data;
for (c = 0; c < (int)entry->components; c++)
entry->data[c] = bvalue[c];
}
break;
case EXIF_FORMAT_SHORT:
{
imushort *usvalue = (imushort*)attrib_data;
for (c = 0; c < (int)entry->components; c++)
exif_set_short(entry->data + format_size * c, byte_order, usvalue[c]);
}
break;
case EXIF_FORMAT_SSHORT:
{
short *svalue = (short*)attrib_data;
for (c = 0; c < (int)entry->components; c++)
exif_set_sshort(entry->data + format_size * c, byte_order, svalue[c]);
}
break;
case EXIF_FORMAT_LONG:
{
int *ivalue = (int*)attrib_data;
for (c = 0; c < (int)entry->components; c++)
exif_set_long(entry->data + format_size * c, byte_order, (unsigned int)ivalue[c]);
}
break;
case EXIF_FORMAT_SLONG:
{
int *ivalue = (int*)attrib_data;
for (c = 0; c < (int)entry->components; c++)
exif_set_slong(entry->data + format_size * c, byte_order, (int)ivalue[c]);
}
break;
case EXIF_FORMAT_RATIONAL:
{
ExifRational v_rat;
int num, den;
float *fvalue = (float*)attrib_data;
for (c = 0; c < (int)entry->components; c++)
{
iGetRational(fvalue[c], &num, &den, 1);
v_rat.numerator = num;
v_rat.denominator = den;
exif_set_rational(entry->data + format_size * c, byte_order, v_rat);
}
}
break;
case EXIF_FORMAT_SRATIONAL:
{
ExifSRational v_srat;
int num, den;
float *fvalue = (float*)attrib_data;
for (c = 0; c < (int)entry->components; c++)
{
iGetRational(fvalue[c], &num, &den, 1);
v_srat.numerator = num;
v_srat.denominator = den;
exif_set_srational(entry->data + format_size * c, byte_order, v_srat);
}
}
break;
case EXIF_FORMAT_FLOAT: // defined but unsupported in libEXIF
case EXIF_FORMAT_DOUBLE: // defined but unsupported in libEXIF
break;
}
/* no need to release the entry here,
it will be handled internally
because we added the entry to the ExifContent */
(void)index;
return 1;
}
static int Centry (lua_State *L) { /** content:entry(tag) */
ExifContent *content = checkcontent(L);
ExifTag tag = exif_tag_from_name(luaL_checkstring(L, 2));
pushentry(L, exif_content_get_entry(content, tag));
return 1;
}
