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GIFwrite.cpp
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GIFwrite.cpp
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/*
GIF Library
Copyright (c) 1999 - 2011 Paul de Leeuw Computers
*/
//note: if the GIF reader returns BAD_FILE on a good file, you have the
//default char type set incorrectly. It should be unsigned.
#include <windows.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "manpwin.h"
#include "Dib.h"
#include "Anim.h"
//#define ALLOWGIFANIMSAVE
#define MAXLINE 150 /* length of line */
#define WRITE_GIF89 TRUE
#define GIFCOMMENT "This GIF file was created by ManpWIN\r"\
"Copyright \251 1997 - 2012 Paul de Leeuw Computers."
#define NO_CODE -1
#define GIFLARGESTCODE 4095 // largest possible code
#define GIFTABLESIZE 5003 // table dimensions
#define GIFSIG87 "GIF87a"
#define GIFSIG89 "GIF89a"
#define GIFVERSION 59
#define GIFSUBVERSION GIFVERSION+2
#define GIFREVISION GIFSUBVERSION+1
#define BAD_OPEN -1
#define BAD_FILE -2
#define BAD_READ -3
#define BAD_ALLOC -4
#define UNSUPPORTED_FUNCTION -5
#define BAD_CREATE -6
#define BAD_WRITE -7
#define TOO_MANY_BITS -8
#define MAXRESULTS -9
/////////////////////////////////////////
// A note about animated GIF saving. The frames exist in 24 bit colour in PGV as all formats and colour depths are
// stored in this format. The Animated GIF file is written as a 256 colour, 8 bits per pixel image. Dithering is used
// to generate an 8 bpp image and the palette is created in this process and is written to the Device Independent
// Bitmap (DIB) for each frame. This is extracted from the dithered DIB and written out as the palette.
/////////////////////////////////////////
static WORD ImageHeight, ImageWidth;
extern CDib Dib; // Device Independent Bitmap class instance
//////////////////////////////////////////////////////////////////////////////////////////////////////
extern HWND GlobalHwnd; // This is the main windows handle
//////////////////////////////////////////////////////////////////////////////////////////////////////
extern BYTE DitherBitsPerPixel; // for reducing bits per pixel
extern BYTE masktable[8];
extern WORD CurrentFrame; // used to increment to the next frame when the timer ticks
extern int file_type;
extern BYTE Stepflag; // single step animated GIFs?
extern HCURSOR hStdCursor;
extern double CurrentDelay; // delay in milliseconds
extern BOOL AnimationForward; // order of file frames
extern void CloseDitherPointers(BYTE);
extern int GetDibPalette(LPBITMAPINFO,BYTE *);
extern LPBITMAPINFOHEADER Dither(WORD);
extern void ShowOutfileMessage(char *);
extern int AnimateGIF(void);
extern int user_data(HWND);
typedef struct {
char sig[6];
WORD screenwidth,screendepth;
BYTE flags,background; // force even Byte boundary on structure
} GIFHEADER;
typedef struct {
WORD left,top,width,depth;
} GIFIMAGEBLOCK;
#define GetChunkyPixel(pxx,nxx) (!((nxx) & 1)) ? (((pxx)[(nxx)>>1] >> 4) & 0x0f) : ((pxx)[(nxx)>>1] & 0x0f)
void GIFDoSkipExtension(FILE * fh);
int GIFDoUnpackImage(FILE * fh,int bits,LPBITMAPINFOHEADER lpbi,int flags);
int GIFWriteScreenDesc(FILE * fh,LPBITMAPINFOHEADER lpbi,LPSTR sig);
int GIFWriteImageDesc(FILE * fh,int i, LPBITMAPINFOHEADER lpbi);
void GIFInitTable(int min_code_size);
int GIFFlush(FILE * fh,int n);
void GIFWriteCode(FILE * fh,int code);
int GIFCompressImage(FILE * fh,LPBITMAPINFOHEADER lpbi);
int GIFCompressAnimImage(FILE * fh,LPBITMAPINFOHEADER lpbi,int i);
int GIFWriteComment(FILE * fh,LPSTR comment);
int GIFGraphicControlExtension (FILE *fh);
static int *oldcode;
static int *currentcode;
static LPSTR newcode;
static BYTE code_buffer[259]; // where the codes go
static int code_size;
static int clear_code;
static int eof_code;
static int bit_offset;
static int byte_offset;
static int bits_left;
static int max_code;
static int free_code;
// Stuff needed to write an animated GIF
extern int TotalFrames; // total number of animation framese
extern AnimStruct ANIM[]; // holds all the date for each animation frame
//extern WORD BackGroundColour; // points to location of background colour in the palette
BOOL RunGIF = FALSE; // are we in the middle of generating a GIF file?
///////////////////////////////////////////////////////////////
// Put a byte out on the appointed stream
///////////////////////////////////////////////////////////////
int putbyte(int byte,FILE *fh)
{
BYTE c;
c = byte & 0xff;
if (fwrite((LPSTR)&c,1, 1, fh) != 1)
return(EOF);
else
return(byte);
}
///////////////////////////////////////////////////////////////
// Get the number of bits per pixel from the control flags
///////////////////////////////////////////////////////////////
WORD GetBitsPerPixel(BYTE flags)
{
int numcolors;
numcolors = 1 << ((flags & 0x07) + 1);
return ((numcolors > 16) ? 8 : ((numcolors > 2) ? 4 : 1));
}
/**************************************************************************
Cleanup
**************************************************************************/
void CleanupGIF(FILE *fp, LPSTR bp, LPSTR extrabuffer)
{
fclose (fp);
CloseDitherPointers(FALSE);
if(extrabuffer != NULL)
delete [] extrabuffer;
if(bp != NULL)
delete [] bp;
}
/**************************************************************************
Write GIF Image to File
**************************************************************************/
int write_gif_file(char *outfile, char *title)
{
char s[MAXLINE];
LPBITMAPINFOHEADER lpbi = NULL;
LPSTR bp = NULL;
DWORD size;
int i;
static HCURSOR hOldCursor;
static HCURSOR hCursor;
FILE *fp;
LPSTR extrabuffer = NULL; // to decode 1, 4 bits to bytes
WORD linesize;
hOldCursor = SetCursor(LoadCursor(NULL, IDC_WAIT));
DitherBitsPerPixel = 8; // just force 8 bits per pixels and be done with it
RunGIF = TRUE; // let us know if user has hit a key (keyboard.cpp)
if ((fp = fopen(outfile,"wb")) == NULL)
{
hCursor = LoadCursor((HINSTANCE)NULL, IDC_ARROW); // Load pointer cursor.
SetCursor(hCursor);
wsprintf(s, "GIF can't open output file: %s", outfile);
MessageBox (GlobalHwnd, s, title, MB_ICONEXCLAMATION | MB_OK);
return -1;
}
Dib = (AnimationForward) ? ANIM[0].animDIB : ANIM[TotalFrames - 1].animDIB;
if (ANIM[0].animFrameData == NULL)
{
MessageBox(GlobalHwnd, "Can't write GIF file due to no image in first frame ", "GIF write", MB_ICONEXCLAMATION | MB_OK);
fclose (fp);
SetCursor(hStdCursor);
return -1;
}
if ((lpbi = Dither(DitherBitsPerPixel)) == NULL) // drop DIB to 8 bits per pixel
{
MessageBox(GlobalHwnd, "Can't write GIF file due to dither fail ", "GIF write", MB_ICONEXCLAMATION | MB_OK);
fclose (fp);
SetCursor(hStdCursor);
return -1;
}
ImageWidth = Dib.DibWidth;
ImageHeight = Dib.DibHeight;
linesize = WIDTHBYTES(ImageWidth * 24); // even if 8 bits/pixel, need to alloc enough for 24 bit output!!
if ((extrabuffer = new char [linesize]) == NULL)
{
wsprintf(s, "Not enough memory: %d bytes for line buffer in JPEG file ", "GIF write", linesize);
MessageBox(GlobalHwnd, s, "GIF write", MB_ICONEXCLAMATION | MB_OK);
CleanupGIF(fp, bp, extrabuffer);
SetCursor(hStdCursor);
return -1;
}
//size = (DWORD)(GIFTABLESIZE * sizeof(int)) + (DWORD)(GIFTABLESIZE * sizeof(int)) + (DWORD)GIFTABLESIZE;
size = (DWORD)(GIFTABLESIZE * sizeof(int)) * 3L; // enough for old code, new code and the GIFTABLE itself
if ((bp = new char [size]) == NULL)
{
MessageBox(GlobalHwnd, "Can't get memory for GIF encode table in file ", "GIF write", MB_ICONEXCLAMATION | MB_OK);
CleanupGIF(fp, bp, extrabuffer);
SetCursor(hStdCursor);
return -1;
}
oldcode = (int *)bp;
currentcode = (int *)(bp + GIFTABLESIZE * sizeof(int));
newcode = (bp + GIFTABLESIZE * sizeof(int) + GIFTABLESIZE * sizeof(int));
#if WRITE_GIF89
if (!GIFWriteScreenDesc(fp,lpbi,GIFSIG89))
#else
if (!GIFWriteScreenDesc(output_file,lpbi,GIFSIG87))
#endif
{
MessageBox(GlobalHwnd, "Can't write screen descriptor in file ", "GIF write", MB_ICONEXCLAMATION | MB_OK);
CleanupGIF(fp, bp, extrabuffer);
SetCursor(hStdCursor);
return -1;
}
GIFGraphicControlExtension(fp);
if (!GIFWriteImageDesc(fp, 0, lpbi)) // just do the original way without writing delay etc
{
MessageBox(GlobalHwnd, "Can't write screen descriptor in file ", "GIF write", MB_ICONEXCLAMATION | MB_OK);
CleanupGIF(fp, bp, extrabuffer);
SetCursor(hStdCursor);
return -1;
}
if (!GIFCompressImage(fp,lpbi))
{
MessageBox(GlobalHwnd, "Can't write GIFCompressImage in file ", "GIF write", MB_ICONEXCLAMATION | MB_OK);
CleanupGIF(fp, bp, extrabuffer);
SetCursor(hStdCursor);
return -1;
}
for (i = 1; i < TotalFrames; i++) // must be an animated GIF or animated cursor
{
/*
if (ANIM[i] == NULL)
{
MessageBox(GlobalHwnd, "Can't write GIF file due to no image in memory ", "GIF write", MB_ICONEXCLAMATION | MB_OK);
fclose (fp);
SetCursor(hStdCursor);
return -1;
}
*/
Dib = (AnimationForward) ? ANIM[i].animDIB : ANIM[TotalFrames - i - 1].animDIB;
// Dib = ANIM[i].animDIB;
if ((lpbi = Dither(DitherBitsPerPixel)) == NULL)
{
MessageBox(GlobalHwnd, "Can't write GIF file due to dither fail ", "GIF write", MB_ICONEXCLAMATION | MB_OK);
CleanupGIF(fp, bp, extrabuffer);
return -1;
}
wsprintf (s, "Writing GIF frame <%d>of<%d>: ", i + 1, TotalFrames);
SetWindowText(GlobalHwnd, s); // Show formatted text in the caption bar
if (!GIFWriteImageDesc(fp, i, lpbi))
{
MessageBox(GlobalHwnd, "Can't write screen descriptor in file ", "GIF write", MB_ICONEXCLAMATION | MB_OK);
CleanupGIF(fp, bp, extrabuffer);
return -1;
}
if (!GIFCompressImage(fp,lpbi))
{
MessageBox(GlobalHwnd, "Can't write GIFCompressImage in file ", "GIF write", MB_ICONEXCLAMATION | MB_OK);
CleanupGIF(fp, bp, extrabuffer);
return -1;
}
CloseDitherPointers(TRUE);
user_data(GlobalHwnd); // allow breaking of loop
if (!RunGIF) // user hit the escape key
{
CleanupGIF(fp, bp, extrabuffer);
return -1;
}
}
#if WRITE_GIF89
if (GIFWriteComment(fp, GIFCOMMENT) < 0)
{
MessageBox(GlobalHwnd, "Can't write comment in file ", "GIF write", MB_ICONEXCLAMATION | MB_OK);
CleanupGIF(fp, bp, extrabuffer);
SetCursor(hStdCursor);
return -1;
}
#endif
if (putbyte(';',fp) == EOF)
{
MessageBox(GlobalHwnd, "Can't write image tag ';' in file ", "GIF write", MB_ICONEXCLAMATION | MB_OK);
CleanupGIF(fp, bp, extrabuffer);
SetCursor(hStdCursor);
return -1;
}
CleanupGIF(fp, bp, extrabuffer);
SetCursor(hStdCursor);
RunGIF = FALSE;
return(TRUE);
}
/**************************************************************************
Start of routines
**************************************************************************/
int GIFWriteScreenDesc(FILE *fh, LPBITMAPINFOHEADER lpbi, LPSTR sig)
{
GIFHEADER gh;
BYTE palette[VGA_PAL_SIZE];
WORD n;
memset((LPSTR)&gh, 0, sizeof(GIFHEADER));
memcpy(gh.sig, sig, 6);
gh.screenwidth = (WORD)lpbi->biWidth;
gh.screendepth = (WORD)lpbi->biHeight;
gh.background = 0;
gh.flags = (BYTE)(0x80 | ((DitherBitsPerPixel - 1) << 4) | ((DitherBitsPerPixel - 1) & 0x07));
if (fwrite((LPSTR)&gh, 1, sizeof(GIFHEADER), fh) != sizeof(GIFHEADER))
return(FALSE);
putbyte(0, fh);
GetDibPalette((LPBITMAPINFO)lpbi, palette);
n = 3 * (1 << DitherBitsPerPixel);
if (fwrite(palette, 1, n, fh) != n)
return(FALSE);
return(TRUE);
}
int GIFGraphicControlExtension (FILE *fh)
{
if (TotalFrames > 0) // this is only needed if we write animation frames
{
putbyte('!',fh); // Extension introducer
putbyte(0xff,fh); // Graphic control extension label
putbyte(0x0b,fh); // block size (= 11)
putbyte('N',fh); // Application Identifier
putbyte('E',fh);
putbyte('T',fh);
putbyte('S',fh);
putbyte('C',fh);
putbyte('A',fh);
putbyte('P',fh);
putbyte('E',fh);
putbyte('2',fh);
putbyte('.',fh);
putbyte('0',fh);
putbyte(0x03,fh); // Application data ???
putbyte(0x01,fh);
putbyte(0x00,fh); // loop animation
putbyte(0x00,fh); // loop animation
putbyte(0x00,fh); // end
}
return(TRUE);
}
int GIFWriteImageDesc(FILE *fh, int i, LPBITMAPINFOHEADER lpbi)
{
GIFIMAGEBLOCK ib;
BYTE flags, transparent_colour;
WORD delay, n, local_colours, planes;
BYTE palette[VGA_PAL_SIZE];
memset((LPSTR)&ib, 0, sizeof(GIFIMAGEBLOCK));
putbyte('!',fh); // Extension introducer
putbyte(0xf9,fh); // Graphic control label
putbyte(0x04,fh); // block size (= 4)
flags = 0;
putbyte(flags,fh);
delay = (WORD)(CurrentDelay/10.0); // CurrentDelay in milliseconds GIF is in 100 ms
if (fwrite((LPSTR)&delay, 1, sizeof(WORD), fh) != sizeof(WORD))
return(FALSE);
transparent_colour = 0;
putbyte(transparent_colour, fh); // transparency index
putbyte(0x00,fh); // block terminator
putbyte(',',fh);
ib.left = 0;
ib.top = 0;
//ib.width = (WORD)ImageWidth;
//ib.depth = (WORD)ImageHeight;
ib.width = (WORD)lpbi->biWidth;
ib.depth = (WORD)lpbi->biHeight;
flags = (BYTE)(DitherBitsPerPixel - 1);
if (TotalFrames > 0)
flags |= 0x80; // force local palette
if (fwrite((LPSTR)&ib, 1, sizeof(GIFIMAGEBLOCK), fh) != sizeof(GIFIMAGEBLOCK))
return(FALSE);
putbyte(flags,fh);
if (flags & 0x80) // local map?
{
planes = (flags & 0x07) + 1;
local_colours = 1 << planes;
GetDibPalette((LPBITMAPINFO)lpbi, palette);
n = 3 * (1 << DitherBitsPerPixel);
if (fwrite(palette, 1, n, fh) != n)
return(FALSE);
}
return(TRUE);
}
void GIFInitTable(int min_code_size)
{
int i;
code_size = min_code_size + 1;
clear_code = (1 << min_code_size);
eof_code = clear_code + 1;
free_code = clear_code + 2;
max_code = (1 << code_size);
for (i = 0; i < GIFTABLESIZE; i++)
*(currentcode + i) = 0;
}
int GIFFlush(FILE *fh, int n)
{
putbyte(n,fh);
if ((int)fwrite((LPSTR)code_buffer, 1, n, fh) != n)
return(FALSE);
else
return(TRUE);
}
void GIFWriteCode(FILE *fh, int code)
{
long temp;
byte_offset = bit_offset >> 3;
bits_left = bit_offset & 7;
if (byte_offset >= 251)
{
GIFFlush(fh,byte_offset);
code_buffer[0] = code_buffer[byte_offset];
bit_offset = bits_left;
byte_offset = 0;
}
if (bits_left > 0)
{
temp = ((long)code << bits_left) | code_buffer[byte_offset];
code_buffer[byte_offset] = (BYTE)temp;
code_buffer[byte_offset+1] = (BYTE)(temp >> 8);
code_buffer[byte_offset+2] = (BYTE)(temp >> 16);
}
else
{
code_buffer[byte_offset] = (BYTE)code;
code_buffer[byte_offset+1]=(BYTE)(code >> 8);
}
bit_offset += code_size;
}
int GIFCompressImage(FILE *fh, LPBITMAPINFOHEADER lpbi)
{
BYTE *linebuffer, *extrabuffer;
int prefix_code;
int suffix_char;
int hx,d,min_code_size;
int bytes_left = 0, next_byte = 0, this_line = 0;
int i;
WORD linewidth;
int percent, display_count;
char s[120];
ImageWidth = (WORD)lpbi->biWidth;
ImageHeight = (WORD)lpbi->biHeight;
percent = 0;
// SetWindowText (GlobalHwnd, "Writing GIF File"); // Show formatted text in the caption bar
//linewidth = width;
linewidth = WIDTHBYTES(ImageWidth * Dib.BitsPerPixel);
if ((linebuffer = new BYTE [linewidth]) == NULL)
return(BAD_ALLOC);
if ((extrabuffer = new BYTE [linewidth]) == NULL)
{
delete [] linebuffer;
return(BAD_ALLOC);
}
min_code_size = DitherBitsPerPixel;
if (min_code_size < 2 || min_code_size > 9)
{
if (min_code_size == 1)
min_code_size = 2;
else
{
delete [] extrabuffer;
delete [] linebuffer;
return(BAD_WRITE);
}
}
putbyte(min_code_size, fh);
bit_offset = 0;
GIFInitTable(min_code_size);
GIFWriteCode(fh,clear_code);
memcpy(linebuffer,LPBimage(lpbi) + WIDTHBYTES((DWORD)ImageWidth * (DWORD)DitherBitsPerPixel)
* (DWORD)(ImageHeight - 1 - this_line++), (DWORD)LPBlinewidth(lpbi));
if (DitherBitsPerPixel == 1)
{
memcpy(extrabuffer,linebuffer,LPBlinewidth(lpbi));
for (i = 0; i < ImageWidth; ++i)
{
if (extrabuffer[i >> 3] & masktable[i & 0x0007])
linebuffer[i] = 1;
else
linebuffer[i] = 0;
}
}
else if(DitherBitsPerPixel > 1 && DitherBitsPerPixel <= 4)
{
memcpy(extrabuffer,linebuffer,LPBlinewidth(lpbi));
for (i = 0; i < ImageWidth; ++i)
{
linebuffer[i]=GetChunkyPixel(extrabuffer,i);
}
}
bytes_left = ImageWidth - 1;
next_byte = 0;
suffix_char = linebuffer[next_byte++];
prefix_code = suffix_char;
for (;;)
{
display_count = (10 * this_line) / ImageHeight;
if (display_count > percent)
{
percent = display_count;
sprintf (s, "Writing File: %d%%", percent * 10);
// SetWindowText(GlobalHwnd, s);
}
if (bytes_left > 0) // we still have bytes left to compress in this line
{
suffix_char = linebuffer[next_byte++];
--bytes_left;
}
else
{
if (this_line >= ImageHeight) // we have compressed all the lines
break;
memcpy(linebuffer,LPBimage(lpbi) + WIDTHBYTES((DWORD)ImageWidth * (DWORD)DitherBitsPerPixel)
* (DWORD)(ImageHeight - 1 - this_line++), (DWORD)LPBlinewidth(lpbi)); // load next line
if(DitherBitsPerPixel == 1)
{
memcpy(extrabuffer,linebuffer,LPBlinewidth(lpbi));
for (i = 0; i < LPBwidth(lpbi); ++i)
{
if (extrabuffer[i >> 3] & masktable[i & 0x0007])
linebuffer[i] = 1;
else
linebuffer[i] = 0;
}
}
else if (DitherBitsPerPixel > 1 && DitherBitsPerPixel <= 4)
{
memcpy(extrabuffer,linebuffer,LPBlinewidth(lpbi));
for (i = 0; i < LPBwidth(lpbi); ++i)
{
linebuffer[i] = GetChunkyPixel(extrabuffer, i);
}
}
bytes_left = ImageWidth - 1;
next_byte = 0;
suffix_char = linebuffer[next_byte++];
}
hx = (prefix_code ^ (suffix_char << 5)) % GIFTABLESIZE;
d = 1;
for (;;) // start the compression
{
if (*(currentcode + hx) == 0)
{
GIFWriteCode(fh,prefix_code);
d = free_code;
if(free_code <= GIFLARGESTCODE)
{
*(oldcode + hx) = prefix_code;
*(newcode + hx) = (BYTE)suffix_char;
*(currentcode + hx) = free_code;
free_code++;
}
if (d == max_code)
{
if (code_size < 12)
{
code_size++;
max_code <<= 1;
}
else
{
GIFWriteCode(fh,clear_code);
GIFInitTable(min_code_size);
}
}
prefix_code = suffix_char;
break;
}
if(*(oldcode + hx) == prefix_code && *(newcode + hx) == suffix_char)
{
prefix_code = *(currentcode + hx);
break;
}
hx += d;
d += 2;
// if (hx >= GIFTABLESIZE)
// hx -= GIFTABLESIZE;
if (hx >= GIFTABLESIZE) // catch any silly values
{
hx -= GIFTABLESIZE;
d = 1;
}
}
}
GIFWriteCode(fh,prefix_code);
GIFWriteCode(fh,eof_code);
if(bit_offset > 0)
GIFFlush(fh,(bit_offset + 7) / 8);
if(!GIFFlush(fh,0))
{
delete [] extrabuffer;
delete [] linebuffer;
return(FALSE);
}
delete [] extrabuffer;
delete [] linebuffer;
return(TRUE);
}
int GIFWriteComment(FILE *fh,LPSTR comment)
{
int n;
n=lstrlen(comment);
putbyte('!',fh);
putbyte(0xfe,fh);
do {
if (n > 255)
{
putbyte(255,fh);
if(fwrite(comment, 1,255, fh) != 255)
return(FALSE);
comment +=255;
n-=255;
}
else
{
putbyte(n,fh);
if((int)fwrite(comment,1,n,fh) != n)
return(FALSE);
putbyte(0,fh);
n=0;
}
} while(n);
return(TRUE);
}