Class: Exiv2::Exif

Inherits:

Object

• Object
• Exiv2::Exif

Defined in:

ext/exif.cpp

Instance Method Summary

• #[](key) ⇒ Object

  Access exif tag by name.

• #[]=(key, value) ⇒ Object

  @exif = 3024 [] — is a universal accessor.

• #clear ⇒ Object

  Clear all exif data in image.

• #count ⇒ Object

  Count of exif tags in image.

• #delete(key) ⇒ Object

  Delete exif value by it’s name.

• #each(*args) ⇒ Object

  Iterates through all exif tags in image.

• #empty? ⇒ Boolean

  Predicate method.

Instance Method Details

#[](key) ⇒ Object

Access exif tag by name

Exiv2::Image.new("a.jpg").exif["Exif.Image.Model"] => "FinePixS2Pro"

# File 'ext/exif.cpp', line 89

static VALUE exiv2_exif_get(VALUE self, VALUE key) {
	__BEGIN
	rbImage* image;
	Data_Get_Struct(self, rbImage, image);

	VALUE strkey = rb_funcall(key, rb_intern("to_s"), 0);
	Exiv2::ExifData &exifData = image->image->exifData();
	
	if(exifData.empty()) {
		return Qnil;
	}
	
    Exiv2::ExifKey exifKey(STR(strkey));
    Exiv2::ExifData::const_iterator pos = exifData.findKey(exifKey);
    if (pos == exifData.end()) {
		return Qnil;
    }
	
	return unmarshall_value(pos->value());
	__NIL_END
}

#[]=(key, value) ⇒ Object

@exif = 3024 [] — is a universal accessor

# File 'ext/exif.cpp', line 117

static VALUE exiv2_exif_set(VALUE self, VALUE key, VALUE value) {
	__BEGIN
	rbImage* image;
	Data_Get_Struct(self, rbImage, image);

	VALUE strkey = rb_funcall(key, rb_intern("to_s"), 0);

	if(!marshall_value(image->image->exifData(), STR(strkey), value)) {
		THROW("Couldn't write %s", STR(strkey));
	}
	
	image->dirty = true;
	return value;
	__NIL_END
}

#clear ⇒ Object

Clear all exif data in image

# File 'ext/exif.cpp', line 193

static VALUE exiv2_exif_clear(VALUE self) {
	__BEGIN
	rbImage* image;
	Data_Get_Struct(self, rbImage, image);

	Exiv2::ExifData &exifData = image->image->exifData();
	
	if(exifData.empty()) {
		return Qnil;
	}
	exifData.clear();
	return self;
	__END
}

#count ⇒ Object

Count of exif tags in image

# File 'ext/exif.cpp', line 211

static VALUE exiv2_exif_count(VALUE self) {
	__BEGIN
	rbImage* image;
	Data_Get_Struct(self, rbImage, image);

	Exiv2::ExifData &exifData = image->image->exifData();
	
	return INT2FIX(exifData.count());
	__END
}

#delete(key) ⇒ Object

Delete exif value by it’s name

# File 'ext/exif.cpp', line 166

static VALUE exiv2_exif_delete(VALUE self, VALUE key) {
	__BEGIN
	rbImage* image;
	Data_Get_Struct(self, rbImage, image);

	VALUE strkey = rb_funcall(key, rb_intern("to_s"), 0);
	Exiv2::ExifData &exifData = image->image->exifData();
	
	if(exifData.empty()) {
		return Qnil;
	}
	
    Exiv2::ExifKey exifKey(STR(strkey));
    Exiv2::ExifData::iterator pos = exifData.findKey(exifKey);
    if (pos == exifData.end()) {
		return Qnil;
    }
	
	std::string v = pos->toString();
	exifData.erase(pos);
	return rb_str_new(v.c_str(), v.length());
	__NIL_END
}

#each(*args) ⇒ Object

Iterates through all exif tags in image

# File 'ext/exif.cpp', line 136

static VALUE exiv2_exif_each(int argc, VALUE *argv, VALUE self) {
	__BEGIN
	rbImage* image;
	Data_Get_Struct(self, rbImage, image);

	VALUE prefix;
	rb_scan_args(argc, argv, "01", &prefix);
	
	Exiv2::ExifData &exifData = image->image->exifData();
	if(exifData.empty()) {
		return Qnil;
	}
	
	Exiv2::ExifData::const_iterator end = exifData.end();
	for(Exiv2::ExifData::const_iterator i = exifData.begin(); i != end; ++i) {
		VALUE key = rb_str_new(i->key().c_str(), i->key().length());
		VALUE val = unmarshall_value(i->value());
		//VALUE val = rb_str_new(i->toString().c_str(), i->toString().length());
		if(prefix != Qnil && INT2FIX(0) != rb_funcall(key, rb_intern("index"), 1, prefix)) {
			continue;
		}
		rb_yield(rb_ary_new3(2, key, val));
	}
	return self;
	__END
}

#empty? ⇒ Boolean

Predicate method. Is exif empty?

Returns:

• (Boolean)

# File 'ext/exif.cpp', line 225

static VALUE exiv2_exif_empty(VALUE self) {
	__BEGIN
	rbImage* image;
	Data_Get_Struct(self, rbImage, image);

	Exiv2::ExifData &exifData = image->image->exifData();
	
	return exifData.empty() ? Qtrue : Qfalse;
	__NIL_END
}