Devoxx UK 2015 Presentation: Miniboxing - Fast Generics for Primitive Types

Transcript

1. scala-miniboxing.org @miniboxing 18th of June 2015 Devoxx United Kingdom London,

   UK scala-miniboxing.org

2. scala-miniboxing.org @miniboxing Vlad URECHE PhD student in the Scala Team

   @ EPFL Working on program transformations in the Scala programming language, focusing on data representation. Contributions to specialization, backend and Scaladoc. @ @VladUreche @VladUreche vlad.ureche@epfl.ch

3. scala-miniboxing.org @miniboxing scala-miniboxing.org

4. scala-miniboxing.org @miniboxing STOP Please ask if things are not clear!

5. scala-miniboxing.org @miniboxing STOP Please ask if things are not clear!

   Really! I mean it!

6. scala-miniboxing.org @miniboxing What is miniboxing? Why use it? How does

   it... ? Conclusion Generics

7. scala-miniboxing.org @miniboxing Compilers Compilers

8. scala-miniboxing.org @miniboxing Compilers Compilers Source code (language 1) compiler C,

   C++, Java, Scala, C#, Haskell, Clojure, ...

9. scala-miniboxing.org @miniboxing Compilers Compilers Source code (language 1) Source code

   (language 2) compiler C, C++, Java, Scala, C#, Haskell, Clojure, ... x86/ARM assembly LLVM bitcode Cuda code JVM bytecode .NET bytecode ...

10. scala-miniboxing.org @miniboxing Compilers Compilers Source code (language 1) Source code

    (language 2) compiler C, C++, Java, Scala, C#, Haskell, Clojure, ... x86/ARM assembly LLVM bitcode Cuda code JVM bytecode .NET bytecode ... Why so much fuss ?

11. scala-miniboxing.org @miniboxing Compilers Compilers Abstraction Imple- mentation compiler

12. scala-miniboxing.org @miniboxing Compilers Compilers Abstraction Imple- mentation compiler Variable

13. scala-miniboxing.org @miniboxing Compilers Compilers Abstraction Imple- mentation compiler Variable Stack

    slot or Processor register or Heap location

14. scala-miniboxing.org @miniboxing Compilers Compilers Abstraction Imple- mentation compiler Variable Stack

    slot or Processor register or Heap location … Implementation details

15. scala-miniboxing.org @miniboxing Generics Don't Exist Generics Don't Exist in the

    JVM in the JVM

16. scala-miniboxing.org @miniboxing Generics Don't Exist Generics Don't Exist in the

    JVM in the JVM Java/ Scala

17. scala-miniboxing.org @miniboxing Generics Don't Exist Generics Don't Exist in the

    JVM in the JVM Java/ Scala

18. scala-miniboxing.org @miniboxing Generics Don't Exist Generics Don't Exist in the

    JVM in the JVM Javac Scalac Java/ Scala

19. scala-miniboxing.org @miniboxing Generics Don't Exist Generics Don't Exist in the

    JVM in the JVM Javac Scalac Generics Java/ Scala

20. scala-miniboxing.org @miniboxing Erased Generics Erased Generics def identity[T](t: T): T

    = t

21. scala-miniboxing.org @miniboxing Erased Generics Erased Generics def identity[T](t: T): T

    = t scalac / javac

22. scala-miniboxing.org @miniboxing Erased Generics Erased Generics def identity[T](t: T): T

    = t def identity(t: Object): Object = t scalac / javac

23. scala-miniboxing.org @miniboxing Erased Generics Erased Generics identity(5)

24. scala-miniboxing.org @miniboxing Erased Generics Erased Generics identity(5) scalac / javac

25. scala-miniboxing.org @miniboxing Erased Generics Erased Generics identity(5) identity(java.lang.Integer.valueOf(5)) scalac /

    javac

26. scala-miniboxing.org @miniboxing Erased Generics Erased Generics identity(5) identity(java.lang.Integer.valueOf(5)) scalac /

    javac Object representation

27. scala-miniboxing.org @miniboxing Erased Generics Erased Generics java.lang.Integer.valueOf(5) boxing is not

    great ... boxing is not great ... inflates heap requirements

28. scala-miniboxing.org @miniboxing Erased Generics Erased Generics java.lang.Integer.valueOf(5) boxing is not

    great ... boxing is not great ... inflates heap requirements produces garbage

29. scala-miniboxing.org @miniboxing Erased Generics Erased Generics java.lang.Integer.valueOf(5) boxing is not

    great ... boxing is not great ... inflates heap requirements produces garbage value is accessed indirectly (slow)

30. scala-miniboxing.org @miniboxing Erased Generics Erased Generics java.lang.Integer.valueOf(5) boxing is not

    great ... boxing is not great ... inflates heap requirements produces garbage value is accessed indirectly (slow) breaks locality guarantees

31. scala-miniboxing.org @miniboxing Specialization Specialization Iulian Dragoș (@jaguarul) (circa 2009)

32. scala-miniboxing.org @miniboxing Specialization Specialization def identity[T](t: T): T = t

33. scala-miniboxing.org @miniboxing Specialization Specialization def identity[T](t: T): T = t

    specialization

34. scala-miniboxing.org @miniboxing Specialization Specialization def identity[T](t: T): T = t

    def identity(t: Object): Object = t specialization

35. scala-miniboxing.org @miniboxing Specialization Specialization def identity[T](t: T): T = t

    def identity(t: Object): Object = t specialization def identity_Z(t: bool): bool = t

36. scala-miniboxing.org @miniboxing Specialization Specialization def identity[T](t: T): T = t

    def identity(t: Object): Object = t specialization def identity_Z(t: bool): bool = t def identity_C(t: char): char = t

37. scala-miniboxing.org @miniboxing Specialization Specialization def identity[T](t: T): T = t

    def identity(t: Object): Object = t specialization def identity_Z(t: bool): bool = t def identity_C(t: char): char = t … (7 other variants)

38. scala-miniboxing.org @miniboxing Specialization Specialization identity(5)

39. scala-miniboxing.org @miniboxing Specialization Specialization identity(5) specialization

40. scala-miniboxing.org @miniboxing Specialization Specialization identity(5) identity_I(5) specialization

41. scala-miniboxing.org @miniboxing Specialization Specialization identity(5) identity_I(5) specialization No boxing, it

    automatically calls the specialized variant for integers

42. scala-miniboxing.org @miniboxing Specialization Specialization def tupled[T1, T2](t1: T1, t2: T2)

    ...

43. scala-miniboxing.org @miniboxing Specialization Specialization def tupled[T1, T2](t1: T1, t2: T2)

    ... specialization

44. scala-miniboxing.org @miniboxing Specialization Specialization def tupled[T1, T2](t1: T1, t2: T2)

    ... // 100 methods (102) specialization

45. scala-miniboxing.org @miniboxing Specialization Specialization def tupled[T1, T2](t1: T1, t2: T2)

    ... // 100 methods (102) specialization

46. scala-miniboxing.org @miniboxing Specialization Specialization def tupled[T1, T2](t1: T1, t2: T2)

    ... // 100 methods (102) specialization Can we do better?

47. scala-miniboxing.org @miniboxing What is miniboxing? Why use it? How does

    it... ? Conclusion Generics

48. scala-miniboxing.org @miniboxing The idea behind The idea behind LONG miniboxing

    miniboxing

49. scala-miniboxing.org @miniboxing The idea behind The idea behind LONG DOUBLE

    miniboxing miniboxing

50. scala-miniboxing.org @miniboxing The idea behind The idea behind LONG DOUBLE

    INT miniboxing miniboxing

51. scala-miniboxing.org @miniboxing The idea behind The idea behind ... LONG

    DOUBLE INT FLOAT SHORT miniboxing miniboxing

52. scala-miniboxing.org @miniboxing The idea behind The idea behind ... LONG

    DOUBLE INT FLOAT SHORT ... LONG DOUBLE INT FLOAT SHORT a long integer miniboxing miniboxing

53. scala-miniboxing.org @miniboxing Miniboxing Miniboxing def identity[T](t: T): T = t

54. scala-miniboxing.org @miniboxing Miniboxing Miniboxing def identity[T](t: T): T = t

    miniboxing

55. scala-miniboxing.org @miniboxing Miniboxing Miniboxing def identity[T](t: T): T = t

    def identity(t: Object): Object = t miniboxing

56. scala-miniboxing.org @miniboxing Miniboxing Miniboxing def identity[T](t: T): T = t

    def identity(t: Object): Object = t miniboxing def identity_M(..., t: long): long = t

57. scala-miniboxing.org @miniboxing Miniboxing Miniboxing def identity[T](t: T): T = t

    def identity(t: Object): Object = t miniboxing def identity_M(..., t: long): long = t long encodes all primitive types

58. scala-miniboxing.org @miniboxing Miniboxing Miniboxing def identity[T](t: T): T = t

    def identity(t: Object): Object = t miniboxing def identity_M(..., t: long): long = t Only 2n variants long encodes all primitive types

59. scala-miniboxing.org @miniboxing Miniboxing Miniboxing identity(3)

60. scala-miniboxing.org @miniboxing Miniboxing Miniboxing identity(3) miniboxing

61. scala-miniboxing.org @miniboxing Miniboxing Miniboxing identity(3) identity_M(..., int2minibox(3)) miniboxing

62. scala-miniboxing.org @miniboxing Miniboxing Miniboxing identity(3) identity_M(..., int2minibox(3)) miniboxing The miniboxed

    variant of identity

63. scala-miniboxing.org @miniboxing Miniboxing Miniboxing identity(3) identity_M(..., int2minibox(3)) miniboxing The miniboxed

    variant of identity Unlike boxing, these conversions do not affect performance

64. scala-miniboxing.org @miniboxing

65. scala-miniboxing.org @miniboxing What is miniboxing? Why use it? How does

    it... ? Conclusion Generics

66. scala-miniboxing.org @miniboxing

67. scala-miniboxing.org @miniboxing Speedups

68. scala-miniboxing.org @miniboxing Speedups Performance advisories

69. scala-miniboxing.org @miniboxing DEMO

70. scala-miniboxing.org @miniboxing Clash of the Lambdas Clash of the Lambdas

71. scala-miniboxing.org @miniboxing

72. scala-miniboxing.org @miniboxing

73. scala-miniboxing.org @miniboxing Clash of the Lambdas Clash of the Lambdas

    • Paper from 2014 • By Aggelos Biboudis, Uni of Athens

74. scala-miniboxing.org @miniboxing Clash of the Lambdas Clash of the Lambdas

    • Paper from 2014 • By Aggelos Biboudis, Uni of Athens • Comparing Steaming support in – in Java 8 – in Scala – in .NET

75. scala-miniboxing.org @miniboxing Clash of the Lambdas Clash of the Lambdas

    • Paper from 2014 • By Aggelos Biboudis, Uni of Athens • Comparing Steaming support in – in Java 8 – in Scala – in .NET • … but Scala did not have streaming support

76. scala-miniboxing.org @miniboxing Clash of the Lambdas Clash of the Lambdas

    • Paper from 2014 • By Aggelos Biboudis, Uni of Athens • Comparing Steaming support in – in Java 8 – in Scala – in .NET • But Scala lacks an equivalent streaming support – Thus the numbers :)

77. scala-miniboxing.org @miniboxing In the meantime... he implemented it

78. scala-miniboxing.org @miniboxing

79. scala-miniboxing.org @miniboxing DEMO

80. scala-miniboxing.org @miniboxing

81. scala-miniboxing.org @miniboxing What is miniboxing? Why use it? How does

    it... ? Conclusion Generics

82. scala-miniboxing.org @miniboxing Warnings Warnings scala> def baz[T](t: T): T =

    t baz: [T](t: T)T scala> baz(4)

83. scala-miniboxing.org @miniboxing Warnings Warnings scala> def baz[T](t: T): T =

    t baz: [T](t: T)T scala> baz[Int](4)

84. scala-miniboxing.org @miniboxing Warnings Warnings scala> def baz[T](t: T): T =

    t baz: [T](t: T)T scala> baz[Int](4) <console>:9: warning: The method baz would benefit from miniboxing type parameter T, since it is instantiated by a primitive type. ...

85. scala-miniboxing.org @miniboxing Call Graph Call Graph def foo[T](t: T): T

    = bar(t)

86. scala-miniboxing.org @miniboxing Call Graph Call Graph def foo[T](t: T): T

    = bar(t) def bar[T](t: T): T = baz(t)

87. scala-miniboxing.org @miniboxing Call Graph Call Graph def foo[T](t: T): T

    = bar(t) def bar[T](t: T): T = baz(t) def baz[T](t: T): T = t

88. scala-miniboxing.org @miniboxing Call Graph Call Graph def foo[T](t: T): T

    = bar(t) def bar[T](t: T): T = baz(t) def baz[T](t: T): T = t call graph

89. scala-miniboxing.org @miniboxing Call Graph Call Graph foo

90. scala-miniboxing.org @miniboxing Call Graph Call Graph foo bar

91. scala-miniboxing.org @miniboxing Call Graph Call Graph foo bar baz

92. scala-miniboxing.org @miniboxing Miniboxed Call Graph Miniboxed Call Graph def foo[@miniboxed

    T](t: T): T = bar(t) def bar[@miniboxed T](t: T): T = baz(t) def baz[@miniboxed T](t: T): T = t

93. scala-miniboxing.org @miniboxing Miniboxed Call Graph Miniboxed Call Graph def foo[@miniboxed

    T](t: T): T = bar(t) def bar[@miniboxed T](t: T): T = baz(t) def baz[@miniboxed T](t: T): T = t miniboxing

94. scala-miniboxing.org @miniboxing Miniboxed Call Graph Miniboxed Call Graph def foo(...):

    ... = bar(t) def foo_M(...): ... = bar_M(t) def bar(...): ... = baz(t) def bar_M(...): ... = baz_M(t) def baz(...): ... = t def baz_M(...): ... = t

95. scala-miniboxing.org @miniboxing Miniboxed Call Graph Miniboxed Call Graph foo foo_M

    bar bar_M baz baz_M

96. scala-miniboxing.org @miniboxing Miniboxed Call Graph Miniboxed Call Graph foo foo_M

    bar bar_M baz baz_M Data is pased in the miniboxed encoding no boxing necessary!

97. scala-miniboxing.org @miniboxing Suboptimal Call Graph Suboptimal Call Graph def foo[@miniboxed

    T](t: T): T = bar(t) def bar[@miniboxed T](t: T): T = baz(t) def baz[@miniboxed T](t: T): T = t

98. scala-miniboxing.org @miniboxing Suboptimal Call Graph Suboptimal Call Graph def foo[@miniboxed

    T](t: T): T = bar(t) def bar[@miniboxed T](t: T): T = baz(t) def baz[@miniboxed T](t: T): T = t

99. scala-miniboxing.org @miniboxing Suboptimal Call Graph Suboptimal Call Graph def foo[@miniboxed

    T](t: T): T = bar(t) def bar[@miniboxed T](t: T): T = baz(t) def baz[@miniboxed T](t: T): T = t miniboxing

100. scala-miniboxing.org @miniboxing Suboptimal Call Graph Suboptimal Call Graph foo foo_M

     bar baz baz_M

101. scala-miniboxing.org @miniboxing Suboptimal Call Graph Suboptimal Call Graph foo foo_M

     bar baz baz_M

102. scala-miniboxing.org @miniboxing Suboptimal Call Graph Suboptimal Call Graph foo foo_M

     bar baz baz_M boxing arguments → warn

103. scala-miniboxing.org @miniboxing Suboptimal Call Graph Suboptimal Call Graph foo foo_M

     bar baz baz_M boxing arguments → warn

104. scala-miniboxing.org @miniboxing Suboptimal Call Graph Suboptimal Call Graph foo foo_M

     bar baz baz_M boxing arguments → warn

105. scala-miniboxing.org @miniboxing Suboptimal Call Graph Suboptimal Call Graph foo foo_M

     bar baz baz_M boxing arguments → warn there is a better version but I can't call it → warn

106. scala-miniboxing.org @miniboxing Suboptimal Call Graph Suboptimal Call Graph scala> object

     Test { | def foo[@miniboxed T](t: T): T = bar(t) | def bar[ T](t: T): T = baz(t) | def baz[@miniboxed T](t: T): T = t | } <console>:10: warning: The method Test.bar would benefit from miniboxing type parameter T, since it is instantiated by miniboxed type parameter T of method foo: def foo[@miniboxed T](t: T): T = bar(t) ^ <console>:11: warning: The following code could benefit from miniboxing specialization if the type parameter T of method bar would be marked as "@miniboxed T": def bar[T](t: T): T = baz(t) ^ defined object Test

107. scala-miniboxing.org @miniboxing Warnings Warnings • Miniboxing tries to avoid boxing

     • When it can't avoid it, it warns you – And you can act on it • Many other warnings – To keep you from shooting yourself in the foot

108. scala-miniboxing.org @miniboxing

109. scala-miniboxing.org @miniboxing Who's that JVM performance expert over there?

110. scala-miniboxing.org @miniboxing Miniboxing Miniboxing • Replaces the library constructs –

     Functions – Arrays – Numeric type classes ... library ... library

111. scala-miniboxing.org @miniboxing Miniboxing Miniboxing • Replaces the library constructs –

     Functions – Arrays – Numeric type classes • Adds – Interfaces to other constructs – Miniboxed state reflection ... library ... library

112. scala-miniboxing.org @miniboxing Miniboxing Miniboxing • Replaces the library constructs –

     Functions – Arrays – Numeric type classes • Adds – Interfaces to other constructs – Miniboxed state reflection ... library ... library Am I inside a miniboxed class? If so, what is T?

113. scala-miniboxing.org @miniboxing What is miniboxing? Why use it? How does

     it... ? Conclusion Generics

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121. scala-miniboxing.org @miniboxing scala-miniboxing.org

122. scala-miniboxing.org @miniboxing scala-miniboxing.org

123. scala-miniboxing.org @miniboxing scala-miniboxing.org tutorials

124. scala-miniboxing.org @miniboxing scala-miniboxing.org tutorials sbt config

125. scala-miniboxing.org @miniboxing scala-miniboxing.org tutorials sbt config examples

126. scala-miniboxing.org @miniboxing scala-miniboxing.org tutorials sbt config examples support

127. scala-miniboxing.org @miniboxing Credits and Thank you-s • Martin Odersky -

     without Scala, there would be no miniboxing • Cristian Talau - developed the initial prototype, as a semester project • Milos Stojanovic - work on warnings, tuple accessors and others • Romain Beguet - work on miniboxed arrays • Eugene Burmako - the value class plugin based on the LDL transformation • Aymeric Genet - developing collection-like benchmarks for the miniboxing plugin • Martin Odersky, for his patient guidance • Dmitry Petrashko, for the many cool discussions we had • Ilya Klyuchnikov and Pablo Guerrero - fixes and commits • Iulian Dragos, for his work on specialization and many explanations • Miguel Garcia, for his original insights that spawned the miniboxing idea • Michel Schinz, for his wonderful comments and enlightening ACC course • Andrew Myers and Roland Ducournau for the discussions we had and the feedback provided • Heather Miller for the eye-opening discussions we had • Vojin Jovanovic, Sandro Stucki, Manohar Jonalagedda and the whole LAMP laboratory in EPFL • Adriaan Moors, for the miniboxing name which stuck :)) • Thierry Coppey, Vera Salvisberg and George Nithin, for the feedback

128. scala-miniboxing.org @miniboxing Credits and Thank you-s • Grzegorz Kossakowski, for

     the many brainstorming sessions on specialization • Erik Osheim, Tom Switzer and Rex Kerr for their guidance on the Scala community side • Sandro, Vojin, Nada, Heather, Manohar - reviews and discussions on the LDL paper • Hubert Plociniczak for the type notation in the LDL paper • Denys Shabalin (@densh), Dmitry Petrashko (@darkdimius) for their patient reviews of the LDL paper • Alexandru Nedelcu (@alex_ndc) - for the functions direction • Stu Hood (@stuhood) - for the initial support, ideas • Julien Truffault (@JulienTruffaut) - for motivating the development of tuple accessors, sticky plugin warnings • Aggelos Biboudis (@biboudis) - for pushing the functions project forward and the stream benchmarks • Tom Switzer (@tixxit) - for pushing the array project forward and the vector benchmarks • Philip Stutz (@PhilipStutz) - for the ideas on warnings • Rex Kerr (@ichoran) - for ideas on reflection • Vlad Patryshev (@vpatryshev) - for organizing the Scala Bay Meetup, wehre I presented once • The Scala Community • The Valhalla Project Architects • The Devoxx, PNWScala and ScalaDays organizers!

129. scala-miniboxing.org @miniboxing scala-miniboxing.org Thank you!

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131. scala-miniboxing.org @miniboxing

132. scala-miniboxing.org @miniboxing scala-miniboxing.org

133. scala-miniboxing.org @miniboxing http://stephenjudkins.github.io/pureimage-presentation/#/

134. scala-miniboxing.org @miniboxing http://stephenjudkins.github.io/pureimage-presentation/#/32

135. scala-miniboxing.org @miniboxing PureImage PureImage • has very nice abstractions –

     generalizes over input, output format – generalizes over pixel format – provides collection-like mapping over images • liked it a lot

136. scala-miniboxing.org @miniboxing PureImage PureImage • took the usual path to

     using miniboxing – code up a mock-up – become familiar with the problem – try out miniboxing on a small scale

137. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up

138. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up abstract class Image[Repr: Pixel]

     { def width: Int def height: Int def apply(x: Int, y: Int): Repr def map[Repr2: Pixel](f: Image[Repr] => Generator[Repr2]): Image[Repr2] }

139. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up abstract class Image[Repr: Pixel]

     { def width: Int def height: Int def apply(x: Int, y: Int): Repr def map[Repr2: Pixel](f: Image[Repr] => Generator[Repr2]): Image[Repr2] } What's a generator?

140. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up abstract class Generator[Repr: Pixel]

     { def width: Int def height: Int def generate(x: Int, y: Int): Repr }

141. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up abstract class Generator[Repr: Pixel]

     { def width: Int def height: Int def generate(x: Int, y: Int): Repr } Why generic? What is pixel?

142. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up Image on disk Indexed

     colors

143. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up Image on disk Indexed

     colors Loaded image 8-bit RGBA channels

144. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up Image on disk Indexed

     colors Loaded image 8-bit RGBA channels Transformed image 8-bit RGBA channels

145. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up Image on disk Indexed

     colors Loaded image 8-bit RGBA channels Transformed image 8-bit RGBA channels Transformed image 8-bit RGBA channels ...

146. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up Image on disk Indexed

     colors Loaded image 8-bit RGBA channels Transformed image 8-bit RGBA channels Image on disk Indexed colors Transformed image 8-bit RGBA channels ...

147. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up Image on disk Indexed

     colors Loaded image 8-bit RGBA channels Transformed image 8-bit RGBA channels Image on disk Indexed colors Transformed image 8-bit RGBA channels ... discretization after each filter => artifacts

148. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up Image on disk Indexed

     colors Loaded image 8-bit RGBA channels Transformed image 8-bit RGBA channels Image on disk Indexed colors Transformed image 8-bit RGBA channels ... discretization after each filter => artifacts double precision RGBA double precision RGBA

149. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up Image on disk Indexed

     colors Loaded image 8-bit RGBA channels Transformed image 8-bit RGBA channels Image on disk Indexed colors Transformed image 8-bit RGBA channels ... discretization after each filter => artifacts double precision RGBA double precision RGBA discretization only when saving the file => better quality

150. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up Image on disk Indexed

     colors Loaded image 8-bit RGBA channels Transformed image 8-bit RGBA channels Image on disk Indexed colors Transformed image 8-bit RGBA channels ... discretization after each filter => artifacts double precision RGBA double precision RGBA discretization only when saving the file => better quality Pixel representation

151. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up abstract class Pixel[Repr: Manifest]

     { def r(t: Repr): Double // red def g(t: Repr): Double // green def b(t: Repr): Double // blue def a(t: Repr): Double // alpha def pack(r: Double, g: Double, b: Double, a: Double): Repr ... }

152. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up abstract class Pixel[Repr: Manifest]

     { def r(t: Repr): Double // red def g(t: Repr): Double // green def b(t: Repr): Double // blue def a(t: Repr): Double // alpha def pack(r: Double, g: Double, b: Double, a: Double): Repr ... } All transformations occur on doubles

153. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up abstract class Pixel[Repr: Manifest]

     { def r(t: Repr): Double // red def g(t: Repr): Double // green def b(t: Repr): Double // blue def a(t: Repr): Double // alpha def pack(r: Double, g: Double, b: Double, a: Double): Repr ... } All transformations occur on doubles But the data can be encoded differently

154. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up object RGBA extends Pixel[Int]

     { ... } object RGBAExtended extends Pixel[Long] { ... }

155. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up object RGBA extends Pixel[Int]

     { ... } object RGBAExtended extends Pixel[Long] { ... } Encoding all channels

156. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up object RGBA extends Pixel[Int]

     { ... } object RGBAExtended extends Pixel[Long] { ... } case class DiscreteChannels[T](r: T, g: T, b: T, a: T) object FullPixel extends FourChannelPixel[Double] object HalfPixel extends FourChannelPixel[Float] Encoding all channels

157. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up object RGBA extends Pixel[Int]

     { ... } object RGBAExtended extends Pixel[Long] { ... } case class DiscreteChannels[T](r: T, g: T, b: T, a: T) object FullPixel extends FourChannelPixel[Double] object HalfPixel extends FourChannelPixel[Float] Storing channels individually Encoding all channels

158. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up

159. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up "More London Office Development

     at Dusk, London, UK - Diliff" by Diliff - Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:More_London_Office_Development_at_Dusk,_London,_UK_-_Diliff.jpg

160. scala-miniboxing.org @miniboxing PureImage Mock-up PureImage Mock-up "More London Office Development

     at Dusk, London, UK - Diliff" by Diliff - Own work. Licensed under CC BY-SA 3.0 via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:More_London_Office_Development_at_Dusk,_London,_UK_-_Diliff.jpg

161. scala-miniboxing.org @miniboxing scala-miniboxing.org Last example is at http://scala-miniboxing.org/example_pureimage.html