Merge pull request #135 from stefanoverna/avif-format

Add support for AVIF format

lib/fastimage.rb

@@ -544,12 +544,9 @@ class FastImage
       case @stream.peek(3).bytes.to_a.last
       when 0
         # http://www.ftyps.com/what.html
-        # HEIC is composed of nested "boxes". Each box has a header composed of
-        # - Size (32 bit integer)
-        # - Box type (4 chars)
-        # - Extended size: only if size === 1, the type field is followed by 64 bit integer of extended size
-        # - Payload: Type-dependent
         case @stream.peek(12)[4..-1]
+        when "ftypavif"
+          :avif
         when "ftypheic"
           :heic
         when "ftypmif1"
@@ -584,7 +581,14 @@ class FastImage
   end
   alias_method :parse_size_for_cur, :parse_size_for_ico
 
-  class Heic # :nodoc:
+  # HEIC/AVIF are a special case of the general ISO_BMFF format, in which all data is encapsulated in typed boxes,
+  # with a mandatory ftyp box that is used to indicate particular file types. Is composed of nested "boxes". Each
+  # box has a header composed of
+  # - Size (32 bit integer)
+  # - Box type (4 chars)
+  # - Extended size: only if size === 1, the type field is followed by 64 bit integer of extended size
+  # - Payload: Type-dependent
+  class IsoBmff # :nodoc:
     def initialize(stream)
       @stream = stream
     end
@@ -735,14 +739,19 @@ class FastImage
     end
   end
 
+  def parse_size_for_avif
+    bmff = IsoBmff.new(@stream)
+    bmff.width_and_height
+  end
+
   def parse_size_for_heic
-    heic = Heic.new(@stream)
-    heic.width_and_height
+    bmff = IsoBmff.new(@stream)
+    bmff.width_and_height
   end
 
   def parse_size_for_heif
-    heic = Heic.new(@stream)
-    heic.width_and_height
+    bmff = IsoBmff.new(@stream)
+    bmff.width_and_height
   end
 
   class Gif # :nodoc:

test/test.rb

@@ -49,7 +49,10 @@ GoodFixtures = {
   "heic/heic-single.heic"=>[:heif,[1440,960]],
   "heic/heic-collection.heic"=>[:heif,[1440,960]],
   "heic/inverted.heic"=>[:heic,[3024, 4032]],
-  "test6.svg" => [:svg, [450, 450]]
+  "test6.svg" => [:svg, [450, 450]],
+  "avif/hato.avif" => [:avif, [3082, 2048]],
+  "avif/fox.avif" => [:avif, [1204, 799]],
+  "avif/kimono.avif" => [:avif, [722, 1024]],
 }
 
 BadFixtures = [
@@ -59,6 +62,7 @@ BadFixtures = [
   "test2.xml",
   "a.CR2",
   "a.CRW",
+  "avif/star.avifs",
 ]
 # man.ico courtesy of http://www.iconseeker.com/search-icon/artists-valley-sample/business-man-blue.html
 # test_rgb.ct courtesy of http://fileformats.archiveteam.org/wiki/Scitex_CT