classes.tex

一套图像处理程序,支持三种图像文件格式,我调试过了,很好用

\chapter{Alphabetical class reference}\label{classref}
\setheader{{\it CHAPTER \thechapter}}{}{}{}{}{{\it CHAPTER \thechapter}}%
\setfooter{\thepage}{}{}{}{}{\thepage}%

\section{\class{CImage}: public CObject}\label{cimage}

\overview{CImage overview}{cimageoverview}

A CImage object represents an image which can be loaded, saved or manipulated
at a pixel level.

\membersection{CImage::CImage}

\func{void}{CImage}{\void}

Default constructor. Use \helpref{ReadFile}{readfile} or \helpref{Create}{create} to initialize
the object.

\func{void}{CImage}{\param{const CBitmap *}{bitmap}}

Constructs a CImage object from a bitmap.

\func{void}{CImage}{\param{const CString\& }{filename=""}, \param{int}{ imageType=-1}}

Reads the image from a file.

{\it imageType} can be one of:

\begin{itemize}\itemsep=0pt
\item CIMAGE\_FORMAT\_BMP
\item CIMAGE\_FORMAT\_GIF
\item CIMAGE\_FORMAT\_JPEG
\item CIMAGE\_FORMAT\_PNG
\end{itemize}

\func{void}{CImage}{\param{const CImage *}{image}}

Constructs a CImage object from another CImage object. In fact, the image data isn't copied
from {\it image}, but the size, depth etc. are copied.

\membersection{CImage::Create}\label{create}

\func{void}{Create}{\param{int}{ width}, \param{int}{ height}, \param{int}{ depth}, \param{int}{ colortype=-1}}

Creates an array of raw bits for the image with the given properties. You must first call
 \helpref{CreateImplementation}{createimplementation} to tell the CImage what type of image it is, or
the type will default to CIMAGE\_FORMAT\_BMP.

\membersection{CImage::CreateImplementation}\label{createimplementation}

\func{BOOL}{CreateImplementation}{\param{const CString\&}{ fileName}, \param{int\&}{ imageType}, \param{int}{ depth}, \param{int}{ colortype=-1}}

Initializes the CImage by creating an internal object that implements loading, saving etc. This should
not often need to be called by an application.

\membersection{CImage::Draw}\label{draw}

\func{BOOL}{Draw}{\param{CDC *}{dc}, \param{int}{ dx=0}, \param{int}{ dy=0}, \param{int}{ dw=-1},
 \param{int}{ dh=-1}, \param{int}{ sx=0}, \param{int}{ sy=0}}

Draws the image on a device context.

{\it dx, dy} specify the top-left corner of the destination rectangle.

{\it dw, dh} specify the width and height of the rectangle to be drawn.

{\it sx, sy} specify the top-left source position to start drawing from.

\membersection{CImage::GetColorType}\label{getcolortype}

\func{int}{GetColorType}{\void}

Returns the colour type of the image: DIB\_RGB\_COLORS or DIB\_PAL\_COLORS.

\membersection{CImage::GetDepth}\label{getdepth}

\func{int}{GetDepth}{\void}

Returns the colour depth of the image.

\membersection{CImage::GetFilename}\label{getfilename}

\func{CString}{GetFilename}{\void}

Returns the current filename associated with the image.

\membersection{CImage::GetFileType}\label{getfiletype}

\func{int}{GetFileType}{\void}

Returns the current type of the image, which can change according to what types
have been loaded or saved. The return value is one of:

\begin{itemize}\itemsep=0pt
\item CIMAGE\_FORMAT\_BMP
\item CIMAGE\_FORMAT\_GIF
\item CIMAGE\_FORMAT\_JPEG
\item CIMAGE\_FORMAT\_PNG
\end{itemize}

\membersection{CImage::GetHeight}\label{getheight}

\func{int}{GetHeight}{\void}

Returns the height of the image in pixels.

\membersection{CImage::GetIndex}\label{getindex}

\func{int}{GetIndex}{\param{int}{ x}, \param{int}{ y}}

Returns the palette index for the pixel at the given position in the image.

\membersection{CImage::GetPalette}\label{getpalette}

\func{CImagePalette *}{GetPalette}{\void}

Returns the palette associated with the image.

\membersection{CImage::GetRGB}\label{getrgb}

\func{BOOL}{GetRGB}{\param{int}{ x}, \param{int}{ y}, \param{byte *}{red}, \param{byte *}{green},
 \param{byte *}{blue}}
 
Returns the RGB values of the pixel at the given position in the image.

\membersection{CImage::GetWidth}\label{getwidth}

\func{int}{GetWidth}{\void}

Returns the width of the image in pixels.

\membersection{CImage::Inside}\label{inside}

\func{BOOL}{Inside}{\param{int}{ x}, \param{int}{ y}}

Returns TRUE if the given point is inside the image.

\membersection{CImage::IsOK}\label{isok}

\func{BOOL}{IsOK}{\void}

Returns TRUE if the CImage is valid. At present, just checks whether the internal
implementation object is valid.

\membersection{CImage::MakeBitmap}\label{makebitmap}

\func{CBitmap *}{MakeBitmap}{\void}

Makes a new CBitmap object from the CImage object. Untested.

\membersection{CImage::ReadFile}\label{readfile}

\func{BOOL}{ReadFile}{\param{const CString\&}{ filename=""}, \param{int}{ imageType=-1}}

Reads a file of the given type.

{\it imageType} can be one of:

\begin{itemize}\itemsep=0pt
\item CIMAGE\_FORMAT\_BMP
\item CIMAGE\_FORMAT\_GIF
\item CIMAGE\_FORMAT\_JPEG
\item CIMAGE\_FORMAT\_PNG
\end{itemize}

If {\it imageType} is -1, the type is deduced from the file extension.

\membersection{CImage::SaveFile}\label{savefile}

\func{BOOL}{SaveFile}{\param{const CString\&}{ filename=""}, \param{int}{ imageType=-1}}

Reads a file of the given type.

{\it imageType} can be one of:

\begin{itemize}\itemsep=0pt
\item CIMAGE\_FORMAT\_BMP
\item CIMAGE\_FORMAT\_GIF (not implemented)
\item CIMAGE\_FORMAT\_JPEG
\item CIMAGE\_FORMAT\_PNG
\end{itemize}

If {\it imageType} is -1, the type is deduced from the file extension.

\membersection{CImage::SetPalette}\label{setpalette}

\func{BOOL}{SetPalette}{\param{CImagePalette *}{palette}}

\func{BOOL}{SetPalette}{\param{int}{ n}, \param{rgb\_color\_struct *}{rgb\_struct}}

\func{BOOL}{SetPalette}{\param{int}{ n}, \param{byte *}{red}, \param{byte *}{green}, \param{byte *}{blue}}

Sets the palette in a variety of ways.

\membersection{CImage::Stretch}\label{stretch}

\func{BOOL}{Stretch}{\param{CDC *}{dc}, \param{int}{ dx=0}, \param{int}{ dy=0}, \param{int}{ dw=-1},
 \param{int}{ dh=-1}, \param{int}{ sx=0}, \param{int}{ sy=0}, \param{int}{ sw=-1}, \param{int}{ sh=-1}}
 
Draws the image on a device context, stretching the image.

{\it dx, dy} specify the top-left corner of the destination rectangle.

{\it dw, dh} specify the width and height of the rectangle to be drawn.

{\it sx, sy} specify the top-left source position to start drawing from.

{\it sh, sh} specify the width and height of the source rectangle.


\section{\class{CImageIterator}}\label{cimageiterator}

\overview{CImageIterator overview}{cimageiteratoroverview}

Use CImageIterator to iterate through rows and bytes of an image.

\membersection{CImageIterator::CImageIterator}

\func{void}{CImageIterator}{\void}

Default constructor.

\func{void}{CImageIterator}{\param{CImage *}{image}}

Constructor, associating an image with the iterator object.

\func{void}{CImageIterator}{\param{CImageImpl *}{imageImpl}}

Constructor, associating an image with the iterator object.

\membersection{CImageIterator::operator CImage *}

\func{}{operator CImageImpl *}{\void}

Operator, `converting' the CImageIterator object to the associated
CImageImpl object.

\membersection{CImageIterator::GetByte}

\func{byte}{GetByte}{\void}

Returns the byte at the current position.

\membersection{CImageIterator::GetRow}

\func{void}{GetRow}{\param{byte *}{buf}, \param{int}{ n}}

Copies the first {\it n} bytes from the current row to {\bf buf}.

\func{ImagePointerType}{GetRow}{\void}

Returns a pointer to the current row.

\membersection{CImageIterator::GetSteps}

\func{void}{GetSteps}{\param{int *}{x}, \param{int *}{y}}

Returns the steps for incrementing/decrementing with NextStep/PrevStep.

\membersection{CImageIterator::ItOK}

\func{BOOL}{ItOK}{\void}

Returns TRUE if the current iterator position is within the image.

\membersection{CImageIterator::NextByte}

\func{BOOL}{NextByte}{\void}

Increments the current position by a byte.

\membersection{CImageIterator::NextRow}

\func{BOOL}{NextRow}{\void}

Increments the current iterator position by a row.

\membersection{CImageIterator::NextStep}

\func{BOOL}{NextStep}{\void}

Increments the current position by the step previously set by \helpref{SetSteps}{setsteps}.

\membersection{CImageIterator::PrevByte}

\func{BOOL}{PrevByte}{\void}

Decrements the current position by a byte.

\membersection{CImageIterator::PrevRow}

\func{BOOL}{PreviousRow}{\void}

Decrements the current iterator position by a row.

\membersection{CImageIterator::PrevStep}

\func{BOOL}{PrevStep}{\void}

Decrements the current position by the step previously set by \helpref{SetSteps}{setsteps}.

\membersection{CImageIterator::Reset}

\func{BOOL}{Reset}{\void}

Resets the iterator position to 0, 0.

\membersection{CImageIterator::SetByte}

\func{void}{SetByte}{\param{byte}{ b}}

Sets the byte at the current position.

\membersection{CImageIterator::SetRow}

\func{void}{SetRow}{\param{byte *}{buf}, \param{int}{ n}}

Copies the first {\it n} bytes from {\bf buf} to the current row. If {\it n} is less than zero,
it is set to the width of the image.

\membersection{CImageIterator::SetSteps}\label{setsteps}

\func{void}{SetSteps}{\param{int}{ x}, \param{int}{ y}}

Set the steps for incrementing/decrementing with NextStep/PrevStep.

\membersection{CImageIterator::SetY}

\func{void}{SetY}{\param{int}{ y}}

Sets the y position (row).

\membersection{CImageIterator::Upset}

\func{BOOL}{Upset}{\void}

Resets the iterator position to the first pixel of the last image row.


\chapter{Topic overviews}\label{topics}
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\setfooter{\thepage}{}{}{}{}{\thepage}%

\section{CImage overview}\label{cimageoverview}

Classes: \helpref{CImage}{cimage}, \helpref{CImageIterator}{cimageiterator}

This overview to be written.

\section{CImageIterator overview}\label{cimageiteratoroverview}

Classes: \helpref{CImageIterator}{cimageiterator}

This class is used for iterating over bytes in an image. For examples of use, see
the CImage source code, e.g. {\tt imajpg.cpp}.