Amebis/wxWidgets
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

PCX handler now working for reading (8bit and 24bit images).

Browse Source 
Still no wxPCXHandler::SaveFile, though.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@3518 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
This commit is contained in:
Guillermo Rodriguez Garcia
1999-08-29 11:52:02 +00:00
parent e08e239b43
commit 4df78dc36e
1 changed files with 218 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

225
src/common/imagpcx.cpp
View File

@@ -3,8 +3,8 @@
// Purpose: wxImage PCX handler
// Author: Guillermo Rodriguez Garcia <guille@iies.es>
// Version: 1.00
// Last rev: 1999/08/24
// Copyright: (c) Guillermo Rodriguez Garcia
// CVS-ID: $Id$
// Copyright: (c) 1999 Guillermo Rodriguez Garcia
// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
@@ -25,6 +25,185 @@
#include "wx/module.h"
#include "wx/log.h"
//-----------------------------------------------------------------------------
// PCX decoding
//-----------------------------------------------------------------------------
void RLEencode(unsigned char *p, unsigned int size, wxOutputStream& s)
{
}
void RLEdecode(unsigned char *p, unsigned int size, wxInputStream& s)
{
unsigned int i, data, cont;
// Read 'size' bytes. The PCX official specs say there will be
// a decoding break at the end of each scanline (but not at the
// end of each plane inside a scanline). Only use this function
// to read one or more _complete_ scanlines. Else, more than
// 'size' bytes might be read and the buffer might overflow.
//
while (size > 0)
{
data = (unsigned char)s.GetC();
// If ((data & 0xC0) != 0xC0), then the value read is a data
// byte. Else, it is a counter (cont = val & 0x3F) and the
// next byte is the data byte.
//
if ((data & 0xC0) != 0xC0)
{
*(p++) = data;
size--;
}
else
{
cont = data & 0x3F;
data = (unsigned char)s.GetC();
for (i = 1; i <= cont; i++)
*(p++) = data;
size -= cont;
}
}
}
/* PCX header */
#define HDR_VERSION 1
#define HDR_ENCODING 2
#define HDR_BITSPERPIXEL 3
#define HDR_XMIN 4
#define HDR_YMIN 6
#define HDR_XMAX 8
#define HDR_YMAX 10
#define HDR_NPLANES 65
#define HDR_BYTESPERLINE 66
/* image formats */
#define IMAGE_8BIT 0 // 8 bpp, 1 plane (8 bit)
#define IMAGE_24BIT 1 // 8 bpp, 3 planes (24 bit)
/* error codes */
#define E_OK 0 // everything was OK
#define E_FORMATO 1 // error in pcx file format
#define E_MEMORIA 2 // error allocating memory
#define E_VERSION 3 // error in pcx version number
// ReadPCX:
// Loads a PCX file into the wxImage object pointed by image.
// Returns E_OK on success, or an error code otherwise (see
// above for error codes)
//
int ReadPCX(wxImage *image, wxInputStream& stream)
{
unsigned char hdr[128]; // PCX header
unsigned char pal[768]; // palette for 8 bit images
unsigned char *p; // space to store one scanline
unsigned char *dst; // pointer into wxImage data
unsigned int width, height; // size of the image
unsigned int bytesperline; // bytes per line (each plane)
int bitsperpixel; // bits per pixel (each plane)
int nplanes; // number of planes
int encoding; // is the image RLE encoded?
int format; // image format (8 bit, 24 bit)
unsigned int i;
off_t pos;
// Read PCX header and check the version number (it must
// be at least 5 or higher for 8 bit and 24 bit images).
//
stream.Read(hdr, 128);
if (hdr[HDR_VERSION] < 5) return E_VERSION;
// Extract all image info from the PCX header.
//
encoding = hdr[HDR_ENCODING];
nplanes = hdr[HDR_NPLANES];
bitsperpixel = hdr[HDR_BITSPERPIXEL];
bytesperline = hdr[HDR_BYTESPERLINE] + 256 * hdr[HDR_BYTESPERLINE + 1];
width = (hdr[HDR_XMAX] + 256 * hdr[HDR_XMAX + 1]) -
(hdr[HDR_XMIN] + 256 * hdr[HDR_XMIN + 1]) + 1;
height = (hdr[HDR_YMAX] + 256 * hdr[HDR_YMAX + 1]) -
(hdr[HDR_YMIN] + 256 * hdr[HDR_YMIN + 1]) + 1;
// Check image format. Currently supported formats are
// 8 bits (8 bpp, 1 plane) and 24 bits (8 bpp, 3 planes).
//
if ((nplanes == 3) && (bitsperpixel == 8))
format = IMAGE_24BIT;
else if ((nplanes == 1) && (bitsperpixel == 8))
format = IMAGE_8BIT;
else
return E_FORMATO;
// If the image is of type IMAGE_8BIT, then there is a
// palette at the end of the file. Read it now before
// proceeding.
//
pos = stream.TellI();
stream.SeekI(-769, wxFromEnd);
if (stream.GetC() != 12)
return E_FORMATO;
stream.Read(pal, 768);
stream.SeekI(pos, wxFromStart);
// Allocate memory for a scanline and resize the image.
//
image->Create(width, height);
if (!image->Ok())
return E_MEMORIA;
if ((p = (unsigned char *) malloc(bytesperline * nplanes)) == NULL)
return E_MEMORIA;
// Now start reading the file, line by line, and store
// the data in the format required by wxImage.
//
dst = image->GetData();
for (; height; height--)
{
if (encoding)
RLEdecode(p, bytesperline * nplanes, stream);
else
stream.Read(p, bytesperline * nplanes);
switch (format)
{
case IMAGE_8BIT:
{
for (i = 0; i < width; i++)
{
*(dst++) = pal[ 3 * (p[i]) ];
*(dst++) = pal[ 3 * (p[i]) + 1];
*(dst++) = pal[ 3 * (p[i]) + 2];
}
break;
}
case IMAGE_24BIT:
{
for (i = 0; i < width; i++)
{
*(dst++) = p[i];
*(dst++) = p[i + bytesperline];
*(dst++) = p[i + 2 * bytesperline];
}
break;
}
}
}
free(p);
return E_OK;
}
//-----------------------------------------------------------------------------
// wxPCXHandler
//-----------------------------------------------------------------------------
@@ -37,25 +216,57 @@ IMPLEMENT_DYNAMIC_CLASS(wxPCXHandler,wxImageHandler)
bool wxPCXHandler::LoadFile( wxImage *image, wxInputStream& stream, bool verbose )
{
int error;
if (!CanRead(stream))
{
if (verbose)
wxLogError(_T("wxPCXHandler: this is not a PCX file"));
return FALSE;
}
image->Destroy();
if (verbose)
wxLogDebug(_T("wxPCXHandler::LoadFile still not implemented"));
if ((error = ReadPCX(image, stream)) != E_OK)
{
if (verbose)
{
switch (error)
{
case E_FORMATO: wxLogError(_T("wxPCXHandler: image format unsupported")); break;
case E_MEMORIA: wxLogError(_T("wxPCXHandler: couldn't allocate memory")); break;
case E_VERSION: wxLogError(_T("wxPCXHandler: version number too low")); break;
default: wxLogError(_T("wxPCXHandler: unknown error !!!"));
}
}
image->Destroy();
return FALSE;
}
return FALSE;
return TRUE;
}
bool wxPCXHandler::SaveFile( wxImage *image, wxOutputStream& stream, bool verbose )
{
if (verbose)
wxLogDebug(_T("wxPCXHandler::SaveFile still not implemented"));
wxLogError(_T("wxPCXHandler::SaveFile still not implemented"));
return FALSE;
}
bool wxPCXHandler::CanRead( wxInputStream& stream )
{
return FALSE;
unsigned char c;
off_t pos;
pos = stream.TellI();
stream.SeekI(0, wxFromStart);
c = stream.GetC();
stream.SeekI(pos, wxFromStart);
// not very safe, but this is all we can get from PCX header :-(
return (c == 10);
}