phase 2 interlacing working

aberant · Jan 1, 2010 · 8f8fc6e · 8f8fc6e
1 parent 00c80e8
commit 8f8fc6e
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Showing 7 changed files with 166 additions and 25 deletions.
diff --git a/lib/spittle.rb b/lib/spittle.rb
@@ -16,3 +16,4 @@
 require 'spittle/processor'
 require 'spittle/mtime_tracker'
 require 'spittle/image_data'
+require 'spittle/deinterlacer'
diff --git a/lib/spittle/deinterlacer.rb b/lib/spittle/deinterlacer.rb
@@ -0,0 +1,77 @@
+class DeInterlacer
+  def initialize(height, width, pixel_width, raw, decoder)
+    @height, @width, @decoder = height, width, decoder
+    @pixel_width = pixel_width
+    @raw = raw.dup
+    @out = Spittle::ImageData.new :scanline_width => width, :pixel_width => pixel_width
+  end
+
+  def process
+    pass1
+    pass2
+    @out
+  end
+
+  def pass1_height
+    @height / 8
+  end
+
+  def pass1_width
+  end
+
+  def pass1
+    sub_width = ((@width / 8) * @pixel_width) + 1
+    sub_height = pass1_height
+    scanline_width = @width / 8
+
+    sub_image = Spittle::ImageData.new(:scanline_width => scanline_width,
+                                   :pixel_width => @pixel_width,
+                                   :data => [])
+    sub_height.times do |line_idx|
+      row = @raw.slice!(0, sub_width)
+      l = @decoder.decode(line_idx, row, sub_image, @pixel_width)
+      sub_image << l
+    end
+    sub_image
+
+    #FUck!
+    idxes = [0, (1..scanline_width - 1).to_a.map{ |i| (i * 8)}.map{|i| i - 1}].flatten
+    rows = [0, (1..sub_height - 1).to_a.map{ |i| i * 8 }.map{|i| i - 1}].flatten
+
+    input = sub_image.to_a
+    rows.each do |row|
+      idxes.each do |idx|
+        pixel = input.take(@pixel_width)
+        @out.set_pixel(row, idx, pixel)
+      end
+    end
+  end
+
+  def pass2
+    sub_width = ((@width / 8) * @pixel_width) + 1
+    sub_height = pass1_height
+    scanline_width = @width / 8
+
+    sub_image = Spittle::ImageData.new(:scanline_width => scanline_width,
+                                   :pixel_width => @pixel_width,
+                                   :data => [])
+    offset = 0
+    sub_height.times do |line_idx|
+      row = @raw.slice!(0, sub_width)
+      sub_image << @decoder.decode(line_idx, row, sub_image, @pixel_width)
+    end
+    sub_image
+
+    #FUck!
+    idxes = (0..scanline_width - 1).to_a.map{ |i| (i * 8) + 4}.map{|i| i - 1}
+    rows = [0, (1..sub_height - 1).to_a.map{ |i| i * 8 }.map{|i| i - 1}].flatten
+
+    input = sub_image.to_a
+    rows.each do |row|
+      idxes.each do |idx|
+        pixel = input.take(@pixel_width)
+        @out.set_pixel(row, idx, pixel)
+      end
+    end
+  end
+end
diff --git a/lib/spittle/image_data.rb b/lib/spittle/image_data.rb
@@ -13,6 +13,26 @@ def scanline_width; @properties[:scanline_width]; end
     def width; scanline_width / pixel_width; end
     def pixel_width; @properties[:pixel_width]; end
 
+    def to_a
+      @data.flatten
+    end
+
+    def set_pixel(row, idx, pixel)
+       return unless pixel
+       @data[row] = [] unless @data[row]
+       row = @data[row]
+       offset = idx * pixel_width
+
+       pixel.each_with_index do |v, pidx|
+         row[offset + pidx] = v
+       end
+    end
+
+    def fetch_pixel(idx, row = 0)
+      offset = idx * pixel_width
+      @data[row].slice(offset, pixel_width)
+    end
+
     # need better checks, because currently compatible is
     # similar color type, or depth.. maybe it doesn't matter...
     def compatible?(image)
@@ -73,6 +93,10 @@ def last
       @data.last
     end
 
+    def rows
+      size
+    end
+
     def <<(row)
       @data << row
       self

diff --git a/lib/spittle/png/image.rb b/lib/spittle/png/image.rb
@@ -99,20 +99,23 @@ def to_image
     def inspect
       "#{@name} (#{height} x #{width}) [color type: #{color_type}, depth: #{depth}]"
     end
-  private
+
     # spike spikey spike
     def decode_interlaced_image( uncompressed )
-      subimage1 = Spittle::ImageData.new(:scanline_width => sub_image_1_width - 1,
-                                     :pixel_width => pixel_width,
-                                     :data => Array.new(sub_image_1_height))
-     offset = 0
-      sub_image_1_height.times do |scanline|
-        end_row = sub_image_1_width + offset
-        row = uncompressed.slice(offset, sub_image_1_width)
-        subimage1[scanline] = decode(scanline, row, subimage1, pixel_width)
-        offset = end_row
-      end
-      subimage1
+      #subimage1 = Spittle::ImageData.new(:scanline_width => sub_image_1_width - 1,
+                                     #:pixel_width => pixel_width,
+                                     #:data => Array.new(sub_image_1_height))
+     #offset = 0
+      #sub_image_1_height.times do |scanline|
+        #end_row = sub_image_1_width + offset
+        #row = uncompressed.slice(offset, sub_image_1_width)
+        #subimage1[scanline] = decode(scanline, row, subimage1, pixel_width)
+        #offset = end_row
+      #end
+      #subimage1
+
+      deinterlacer = DeInterlacer.new(height, width, pixel_width, uncompressed, self)
+      deinterlacer.process
     end
 
     def sub_image_1_width

diff --git a/spec/integration/interlace_spec.rb b/spec/integration/interlace_spec.rb
@@ -1,26 +1,53 @@
 require File.expand_path(File.dirname(__FILE__) + '/../spec_helper')
 
+
+#Interlaced Image color breakdown
+#
+# pass 1: (1,1,1)
+# pass 2: (42,42,42)
+# pass 3: (103, 103, 0)
+# pass 4: (104, 0, 0)
+# pass 5: (0, 105, 0)
+# pass 6: (0, 0, 106)
+# pass 6: (207, 207)
+
 describe "reading interlaced images" do
-  before :all do
-    @image_dir = File.join( File.dirname( __FILE__ ), "interlaced_images" )
-  end
-
-  before :each do
-    @image = PNG::Image.open( @image_dir + "/interlaced-16x16-first-image.png" )
+  before do
+    begin
+      @image_dir = File.join( File.dirname( __FILE__ ), "interlaced_images" )
+      @image = PNG::Image.open( @image_dir + "/interlaced-16x16.png" )
+      @result = @image.to_image
+    rescue Exception => e
+      puts e.backtrace.join("\n")
+      raise e
+    end
   end
-  
+
   describe "sanity checks" do
     it "knows the images width" do
       @image.width.should == 16
     end
-  
+
     it "knows the images height" do
       @image.height.should == 16
     end
   end
-
-  it "can read the first sub-image from an interlaced image" do
-    # should be the only colored pixels in the image.. with four different colors
-    @image.to_image.should == [[255, 127, 63, 63, 127, 255], [33, 66, 99, 192, 255, 127]]
+
+  describe "pass extraction" do
+    it "can read the first sub-image from an interlaced image" do
+      @result.fetch_pixel(0).should == [1,1,1]
+      @result.fetch_pixel(7).should == [1,1,1]
+
+      @result.fetch_pixel(0, 7).should == [1,1,1]
+      @result.fetch_pixel(7, 7).should == [1,1,1]
+    end
+
+    it "can read the second sub-image" do 
+      @result.fetch_pixel(3).should == [42,42,42]
+      @result.fetch_pixel(11).should == [42,42,42]
+
+      @result.fetch_pixel(3, 7).should == [42,42,42]
+      @result.fetch_pixel(11, 7).should == [42,42,42]
+    end
   end
-end
+end
diff --git a/spec/integration/interlaced_images/interlaced-16x16.png b/spec/integration/interlaced_images/interlaced-16x16.png
diff --git a/spec/lib/image_data_spec.rb b/spec/lib/image_data_spec.rb
@@ -46,4 +46,13 @@
   it "will return the last scanline given a current index" do 
     @id.last_scanline(1).should == [1,2,3]
   end
+
+  describe "fetch_pixel" do
+    it "can fetch a given pixel" do 
+      @id.fetch_pixel(0).should == [1,2,3]
+    end
+    it "can fetch across all rows" do 
+      @id.fetch_pixel(0, 1).should == [4,5,6]
+    end
+  end
 end