(************** Content-type: application/mathematica **************
                     CreatedBy='Mathematica 5.2'

                    Mathematica-Compatible Notebook

This notebook can be used with any Mathematica-compatible
application, such as Mathematica, MathReader or Publicon. The data
for the notebook starts with the line containing stars above.

To get the notebook into a Mathematica-compatible application, do
one of the following:

* Save the data starting with the line of stars above into a file
  with a name ending in .nb, then open the file inside the
  application;

* Copy the data starting with the line of stars above to the
  clipboard, then use the Paste menu command inside the application.

Data for notebooks contains only printable 7-bit ASCII and can be
sent directly in email or through ftp in text mode.  Newlines can be
CR, LF or CRLF (Unix, Macintosh or MS-DOS style).

NOTE: If you modify the data for this notebook not in a Mathematica-
compatible application, you must delete the line below containing
the word CacheID, otherwise Mathematica-compatible applications may
try to use invalid cache data.

For more information on notebooks and Mathematica-compatible 
applications, contact Wolfram Research:
  web: http://www.wolfram.com
  email: info@wolfram.com
  phone: +1-217-398-0700 (U.S.)

Notebook reader applications are available free of charge from 
Wolfram Research.
*******************************************************************)

(*CacheID: 232*)


(*NotebookFileLineBreakTest
NotebookFileLineBreakTest*)
(*NotebookOptionsPosition[     11340,        412]*)
(*NotebookOutlinePosition[     12085,        437]*)
(*  CellTagsIndexPosition[     12041,        433]*)
(*WindowFrame->Normal*)



Notebook[{

Cell[CellGroupData[{
Cell["Digital Images", "Title"],

Cell["\<\
Wavelet Workshop
June 7-10, 2006
University of St. Thomas\
\>", "Subtitle"],

Cell["Objectives", "Subsubtitle"],

Cell[TextData[{
  "The purpose of this notebook is to give you a brief introduction to the \
software package ",
  StyleBox["WaveletFunctions",
    FontFamily->"Courier"],
  " and show you how to use it to load images.  Some basic image manipulation \
is illustrated as well."
}], "Text"],

Cell[CellGroupData[{

Cell["WaveletFunctions", "Subsubtitle",
  InitializationCell->True],

Cell[TextData[{
  "This cell initializes every time you open the notebook.  It loads the ",
  StyleBox["Mathematica",
    FontSlant->"Italic"],
  " package ",
  StyleBox["WaveletFunctions",
    FontFamily->"Courier"],
  " for use in subsequent computations."
}], "Text",
  InitializationCell->True],

Cell[BoxData[{
    \(<< WaveletFunctions`WaveletFunctions`\), "\[IndentingNewLine]", 
    \(\(flashdir = "\<E:/Images/\>";\)\), "\[IndentingNewLine]", 
    \(\(Print["\<The flash drive directory is \>", 
        flashdir, "\<.\>"];\)\), "\[IndentingNewLine]", 
    \(\(imgurl = \
"\<http://cam.mathlab.stthomas.edu/pvf/Math316/TestImages/\>";\)\), "\
\[IndentingNewLine]", 
    \(\(Print["\<The URL for images is \>", imgurl, "\<.\>"];\)\)}], "Input",
  InitializationCell->True]
}, Open  ]],

Cell[CellGroupData[{

Cell["Help on WaveletFunctions", "Subsubtitle"],

Cell[TextData[{
  "If you ever need help with ",
  StyleBox["WaveletFunctions",
    FontFamily->"Courier"],
  ", go to ",
  StyleBox["Help",
    FontSlant->"Italic"],
  ", then ",
  StyleBox["Help Browser",
    FontSlant->"Italic"],
  ", and click on ",
  StyleBox["AddOns & Links",
    FontSlant->"Italic"],
  ".  If you scroll down you will find ",
  StyleBox["WaveletFunctions",
    FontFamily->"Courier"],
  ".  "
}], "Text"],

Cell[CellGroupData[{

Cell["Loading a Digital Image", "Section"],

Cell[TextData[{
  StyleBox["WaveletFunctions",
    FontFamily->"Courier"],
  " comes with a command called ",
  StyleBox["ReadImage",
    FontWeight->"Bold"],
  ".  This command essentially needs one argument - the location, either on a \
computer or on the internet, of a digital image.  In the case of a grayscale \
image, ",
  StyleBox["ReadImage",
    FontWeight->"Bold"],
  " returns a matrix (named ",
  StyleBox["A",
    FontWeight->"Bold"],
  " in the commands below) containing the gray scale intensity values for \
each pixel.  \n\nHere are some examples."
}], "Text"],

Cell[BoxData[{
    \(\(A = 
        ReadImage[
          flashdir <> "\<garfield_gray.jpg\>"];\)\), "\[IndentingNewLine]", 
    \(\(A = 
        ReadImage[
          imgurl <> "\<garfield_gray.jpg\>"];\)\), "\[IndentingNewLine]", 
    \(\(Print["\<The dimensions of the image are \>", 
        Dimensions[A]];\)\)}], "Input"],

Cell[TextData[{
  "Here is the first row of ",
  StyleBox["A",
    FontWeight->"Bold"],
  ":"
}], "Text"],

Cell[BoxData[
    \(A[\([1]\)]\)], "Input"],

Cell[TextData[{
  "Here is the 100th row of ",
  StyleBox["A",
    FontWeight->"Bold"],
  ":"
}], "Text"],

Cell[BoxData[
    \(A[\([100]\)]\)], "Input"],

Cell[TextData[{
  "Here is the 100th column of ",
  StyleBox["A",
    FontWeight->"Bold"],
  ":"
}], "Text"],

Cell[BoxData[
    \(\(Transpose[A]\)[\([100]\)]\)], "Input"],

Cell[TextData[{
  "There are two additional options (hereafter ",
  StyleBox["directive",
    FontWeight->"Bold"],
  "s) for ",
  StyleBox["ReadImage",
    FontWeight->"Bold"],
  ".    The first is called ",
  StyleBox["PrintInfo",
    FontWeight->"Bold"],
  " and if set to ",
  StyleBox["True",
    FontWeight->"Bold"],
  ", will give you the dimensions and type (grayscale, color) of image you \
have read.  The ",
  StyleBox["PowersOfTwo",
    FontWeight->"Bold"],
  " option, if set (say to K) will chop off enough rows on the bottom and \
columns on the left to make the dimensions of the image divisible by ",
  Cell[BoxData[
      \(2\^K\)]],
  ".  This is really handy when students pull their own images off the web \
and we need the dimensions to be divisible by ",
  Cell[BoxData[
      \(2\^K\)]],
  "."
}], "Text"],

Cell[BoxData[{
    \(\(A = 
        ReadImage[flashdir <> "\<garfield_gray.jpg\>", 
          PrintInfo \[Rule] True];\)\), "\[IndentingNewLine]", 
    \(\(B = 
        ReadImage[flashdir <> "\<garfield.jpg\>", 
          PrintInfo \[Rule] True];\)\)}], "Input"],

Cell[BoxData[
    \(\(\(\[IndentingNewLine]\)\(\(A = 
        ReadImage[flashdir <> "\<garfield_gray.jpg\>", 
          PrintInfo \[Rule] True, 
          PowersOfTwo \[Rule] 4];\)\[IndentingNewLine]
    \(Print["\<The new dimensions of A are \>", 
        Dimensions[A], "\<.\>"];\)\)\)\)], "Input"],

Cell[TextData[{
  "Note that ",
  StyleBox["B",
    FontWeight->"Bold"],
  " was processed as a color image.  This means that ",
  StyleBox["B",
    FontWeight->"Bold"],
  " returned three matrices - the first matrix is the ",
  StyleBox["red",
    FontColor->RGBColor[1, 0, 0]],
  " portion of the image (with values 0 to 255), the second matrix is the ",
  StyleBox["green",
    FontColor->RGBColor[0, 1, 0]],
  " portion of the image, and the third matrix is the ",
  StyleBox["blue",
    FontColor->RGBColor[0, 0, 1]],
  " portion of the image.\n\nNotation-wise, we have the matrices",
  StyleBox[" B[[ 1 ]]",
    FontWeight->"Bold"],
  " (red), ",
  StyleBox["B[[ 2 ]]",
    FontWeight->"Bold"],
  " (blue), and ",
  StyleBox["B[[ 3 ]]",
    FontWeight->"Bold"],
  " (green), but it might be easier to make the call as follows:"
}], "Text"],

Cell[BoxData[
    \(\({red, green, blue}\  = \ 
        ReadImage[flashdir <> "\<garfield.jpg\>", 
          PrintInfo \[Rule] True];\)\)], "Input"]
}, Open  ]],

Cell[CellGroupData[{

Cell["Plotting a Digital Image", "Section"],

Cell[TextData[{
  "It is easy to plot digital images read with ",
  StyleBox["ReadImage",
    FontWeight->"Bold"],
  " in ",
  StyleBox["Mathematica",
    FontSlant->"Italic"],
  ".  The command is called ",
  StyleBox["ImagePlot",
    FontWeight->"Bold"],
  " (I wish now I would have called it PlotImage to parallel ReadImage .... \
).  \n\nOnce you have an image loaded via ",
  StyleBox["ReadImage",
    FontWeight->"Bold"],
  ", here's what you can do:"
}], "Text"],

Cell[BoxData[
    \(\(ImagePlot[A];\)\)], "Input"],

Cell[BoxData[
    \(\(ImagePlot[B];\)\)], "Input"],

Cell[BoxData[
    \(\(ImagePlot[{red, green, blue}];\)\)], "Input"],

Cell[TextData[{
  "You can plot individual channels of a color image if you like.  It will be \
grayscale by default, but if you want to see it in its original color, simply \
add the directive ",
  StyleBox["ChannelColor",
    FontWeight->"Bold"],
  ":"
}], "Text"],

Cell[BoxData[{
    \(\(ImagePlot[red];\)\), "\[IndentingNewLine]", 
    \(\(ImagePlot[red, 
        ChannelColor \[Rule] Red];\)\), "\[IndentingNewLine]", 
    \(\(ImagePlot[green, 
        ChannelColor \[Rule] Green];\)\), "\[IndentingNewLine]", 
    \(\(ImagePlot[blue, 
        ChannelColor \[Rule] Blue];\)\), "\[IndentingNewLine]", 
    \(\(ImagePlot[{red, green, blue}];\)\)}], "Input"]
}, Open  ]],

Cell[CellGroupData[{

Cell["Manipulating Images", "Section"],

Cell["\<\
Once you have an image loaded and know how to plot it, you can do all kinds \
of things with it.  

Convert color to grayscale:\
\>", "Text"],

Cell[BoxData[
    \(\(ImagePlot[\((red + green + blue)\)/3];\)\)], "Input"],

Cell["Darken the image", "Text"],

Cell[BoxData[
    \(\(ImagePlot[A/2];\)\)], "Input"],

Cell["Image negative", "Text"],

Cell[BoxData[
    \(\(ImagePlot[255 - A];\)\)], "Input"],

Cell["Color negative", "Text"],

Cell[BoxData[
    \(\(ImagePlot[255 - {red, green, blue}];\)\)], "Input"],

Cell["Flip it upside down", "Text"],

Cell[BoxData[
    \(ImagePlot[Reverse[A]]\)], "Input"],

Cell["What does the transpose do?", "Text"],

Cell[BoxData[
    \(\(ImagePlot[Transpose[A]];\)\)], "Input"],

Cell["\<\
The previous cell is basically a rotation of the image counterclockwise 90 \
degrees.   In the cell below, can you write code to rotate the image \
clockwise 90 degrees?\
\>", "Text"],

Cell[BoxData[
    \( (*\ Remove\ this\ comment\ and\ put\ code\ here\ *) \)], "Input",
  FontColor->RGBColor[0, 0, 1]]
}, Open  ]],

Cell[CellGroupData[{

Cell["Converting Color Images to YCbCr Space", "Section"],

Cell[TextData[{
  StyleBox["WaveletFunctions",
    FontFamily->"Courier"],
  " contains a command for converting from RGB color space to YCbCr space.  \
The command is called ",
  StyleBox["RGBtoYCbCr",
    FontWeight->"Bold"],
  ".  Here is an example call:"
}], "Text"],

Cell[BoxData[{
    \(\({Y, Cb, Cr}\  = \ 
        RGBtoYCbCr[{red, green, blue}];\)\), "\[IndentingNewLine]", 
    \(\(ImagePlot[Y, 
        LinearScaling \[Rule] True];\)\), "\[IndentingNewLine]", 
    \(\(ImagePlot[Cb, 
        LinearScaling \[Rule] True];\)\), "\[IndentingNewLine]", 
    \(\(ImagePlot[Cr, LinearScaling \[Rule] True];\)\)}], "Input"],

Cell[TextData[{
  "Note that I have used the directive ",
  StyleBox["LinearScaling",
    FontWeight->"Bold"],
  " set to ",
  StyleBox["True",
    FontWeight->"Bold"],
  ".  This maps the minimum value of the matrix to 0 and the maximum value of \
the matrix to 255."
}], "Text"],

Cell[TextData[{
  "You can convert back to RGB space using the command ",
  StyleBox["YCbCrtoRGB",
    FontWeight->"Bold"],
  ":"
}], "Text"],

Cell[BoxData[{
    \(\({red, green, blue} = 
        YCbCrtoRGB[{Y, Cb, Cr}];\)\), "\[IndentingNewLine]", 
    \(\(ImagePlot[{red, green, blue}];\)\)}], "Input"]
}, Open  ]]
}, Open  ]]
}, Open  ]]
},
FrontEndVersion->"5.2 for Microsoft Windows",
ScreenRectangle->{{0, 1024}, {0, 685}},
AutoGeneratedPackage->None,
ScreenStyleEnvironment->"Presentation",
WindowSize->{1016, 651},
WindowMargins->{{0, Automatic}, {Automatic, 0}},
StyleDefinitions -> "Report.nb"
]

(*******************************************************************
Cached data follows.  If you edit this Notebook file directly, not
using Mathematica, you must remove the line containing CacheID at
the top of  the file.  The cache data will then be recreated when
you save this file from within Mathematica.
*******************************************************************)

(*CellTagsOutline
CellTagsIndex->{}
*)

(*CellTagsIndex
CellTagsIndex->{}
*)

(*NotebookFileOutline
Notebook[{

Cell[CellGroupData[{
Cell[1776, 53, 31, 0, 117, "Title"],
Cell[1810, 55, 85, 4, 143, "Subtitle"],
Cell[1898, 61, 33, 0, 67, "Subsubtitle"],
Cell[1934, 63, 288, 7, 63, "Text"],

Cell[CellGroupData[{
Cell[2247, 74, 67, 1, 67, "Subsubtitle",
  InitializationCell->True],
Cell[2317, 77, 298, 9, 63, "Text",
  InitializationCell->True],
Cell[2618, 88, 479, 9, 155, "Input",
  InitializationCell->True]
}, Open  ]],

Cell[CellGroupData[{
Cell[3134, 102, 47, 0, 67, "Subsubtitle"],
Cell[3184, 104, 429, 17, 64, "Text"],

Cell[CellGroupData[{
Cell[3638, 125, 42, 0, 96, "Section"],
Cell[3683, 127, 578, 16, 129, "Text"],
Cell[4264, 145, 325, 8, 103, "Input"],
Cell[4592, 155, 105, 5, 40, "Text"],
Cell[4700, 162, 43, 1, 51, "Input"],
Cell[4746, 165, 105, 5, 40, "Text"],
Cell[4854, 172, 45, 1, 51, "Input"],
Cell[4902, 175, 108, 5, 40, "Text"],
Cell[5013, 182, 60, 1, 51, "Input"],
Cell[5076, 185, 828, 26, 128, "Text"],
Cell[5907, 213, 262, 6, 77, "Input"],
Cell[6172, 221, 300, 6, 129, "Input"],
Cell[6475, 229, 845, 26, 150, "Text"],
Cell[7323, 257, 148, 3, 51, "Input"]
}, Open  ]],

Cell[CellGroupData[{
Cell[7508, 265, 43, 0, 96, "Section"],
Cell[7554, 267, 470, 15, 106, "Text"],
Cell[8027, 284, 50, 1, 51, "Input"],
Cell[8080, 287, 50, 1, 51, "Input"],
Cell[8133, 290, 67, 1, 51, "Input"],
Cell[8203, 293, 266, 7, 62, "Text"],
Cell[8472, 302, 392, 8, 155, "Input"]
}, Open  ]],

Cell[CellGroupData[{
Cell[8901, 315, 38, 0, 96, "Section"],
Cell[8942, 317, 151, 5, 84, "Text"],
Cell[9096, 324, 75, 1, 51, "Input"],
Cell[9174, 327, 32, 0, 40, "Text"],
Cell[9209, 329, 52, 1, 51, "Input"],
Cell[9264, 332, 30, 0, 40, "Text"],
Cell[9297, 334, 56, 1, 51, "Input"],
Cell[9356, 337, 30, 0, 40, "Text"],
Cell[9389, 339, 73, 1, 51, "Input"],
Cell[9465, 342, 35, 0, 40, "Text"],
Cell[9503, 344, 54, 1, 51, "Input"],
Cell[9560, 347, 43, 0, 40, "Text"],
Cell[9606, 349, 61, 1, 51, "Input"],
Cell[9670, 352, 193, 4, 62, "Text"],
Cell[9866, 358, 118, 2, 51, "Input"]
}, Open  ]],

Cell[CellGroupData[{
Cell[10021, 365, 57, 0, 96, "Section"],
Cell[10081, 367, 271, 8, 63, "Text"],
Cell[10355, 377, 354, 7, 129, "Input"],
Cell[10712, 386, 280, 9, 62, "Text"],
Cell[10995, 397, 141, 5, 40, "Text"],
Cell[11139, 404, 161, 3, 77, "Input"]
}, Open  ]]
}, Open  ]]
}, Open  ]]
}
]
*)



(*******************************************************************
End of Mathematica Notebook file.
*******************************************************************)