www.pudn.com > giflib12.zip > GIFRSIZE.C

/***************************************************************************** 
*   "Gif-Lib" - Yet another gif library.				     * 
*									     * 
* Written by:  Gershon Elber				Ver 0.1, Jul. 1989   * 
****************************************************************************** 
* Program to resize GIF by given factors horizontally and vertically.	     * 
* Options:								     * 
* -q : quite printing mode.						     * 
* -S x y : scale into size as specified by x and y.			     * 
* -s r : resize both x & y direction by factor r.			     * 
* -x r : resize the x direction (horizontally) by factor r.		     * 
* -y r : resize the y direction (vertically) by factor r.		     * 
* -h : on line help.							     * 
****************************************************************************** 
* History:								     * 
* 4 Jul 89 - Version 1.0 by Gershon Elber.				     * 
* 22 Dec 89 - Fix minor bag in discarding last line of input (Version 1.1).  * 
* 3 Aug 91 - make it scale by an arbitrary size value.			     * 
*****************************************************************************/ 
 
#ifdef __MSDOS__ 
#include  
#include  
#endif /* __MSDOS__ */ 
 
#include  
#include  
#include  
#include "gif_lib.h" 
#include "getarg.h" 
 
#define PROGRAM_NAME	"GifRSize" 
 
#define MAX_SCALE	16.0			  /* Maximum scaling factor. */ 
 
#ifdef __MSDOS__ 
extern unsigned int 
    _stklen = 16384;			     /* Increase default stack size. */ 
#endif /* __MSDOS__ */ 
 
#ifdef SYSV 
static char *VersionStr = 
        "Gif library module,\t\tGershon Elber\n\ 
	(C) Copyright 1989 Gershon Elber, Non commercial use only.\n"; 
static char 
    *CtrlStr = "GifRSize q%- S%-X|Y!d!d s%-Scale!F x%-XScale!F y%-YScale!F h%- GifFile!*s"; 
#else 
static char 
    *VersionStr = 
	PROGRAM_NAME 
	GIF_LIB_VERSION 
	"	Gershon Elber,	" 
	__DATE__ ",   " __TIME__ "\n" 
	"(C) Copyright 1989 Gershon Elber, Non commercial use only.\n"; 
static char 
    *CtrlStr = 
	PROGRAM_NAME 
	" q%- S%-X|Y!d!d s%-Scale!F x%-XScale!F y%-YScale!F h%- GifFile!*s"; 
#endif /* SYSV */ 
 
/* Make some variables global, so we could access them faster: */ 
static GifPixelType 
    BackGroundColor = 0; 
static double 
    XScale = 0.5, 
    YScale = 0.5; 
static int 
    XSize = 0, 
    YSize = 0; 
 
static void ResizeLine(GifRowType LineIn, GifRowType LineOut, 
		      int InLineLen, int OutLineLen); 
static void QuitGifError(GifFileType *GifFileIn, GifFileType *GifFileOut); 
 
/****************************************************************************** 
* Interpret the command line and scan the given GIF file.		      * 
******************************************************************************/ 
void main(int argc, char **argv) 
{ 
    int	i, iy, last_iy, l, t, w, h, Error, NumFiles, ExtCode, 
	ImageNum = 0, 
	SizeFlag = FALSE, 
	ScaleFlag = FALSE, 
	XScaleFlag = FALSE, 
	YScaleFlag = FALSE, 
	HelpFlag = FALSE; 
    double Scale, y; 
    GifRecordType RecordType; 
    char s[80]; 
    GifByteType *Extension; 
    GifRowType LineIn, LineOut; 
    char **FileName = NULL; 
    GifFileType *GifFileIn = NULL, *GifFileOut = NULL; 
 
    if ((Error = GAGetArgs(argc, argv, CtrlStr, 
		&GifQuitePrint, &SizeFlag, &XSize, &YSize, &ScaleFlag, &Scale, 
		&XScaleFlag, &XScale, &YScaleFlag, &YScale, 
		&HelpFlag, &NumFiles, &FileName)) != FALSE || 
		(NumFiles > 1 && !HelpFlag)) { 
	if (Error) 
	    GAPrintErrMsg(Error); 
	else if (NumFiles > 1) 
	    GIF_MESSAGE("Error in command line parsing - one GIF file please."); 
	GAPrintHowTo(CtrlStr); 
	exit(1); 
    } 
 
    if (HelpFlag) { 
	fprintf(stderr, VersionStr); 
	GAPrintHowTo(CtrlStr); 
	exit(0); 
    } 
 
    /* If specific direction was set, set other direction to 1: */ 
    if (!XScaleFlag && YScaleFlag) XScale = 1.0; 
    if (!YScaleFlag && XScaleFlag) YScale = 1.0; 
 
    /* If the specific direction was not set, but global one did use it: */ 
    if (!XScaleFlag && ScaleFlag) XScale = Scale; 
    if (!YScaleFlag && ScaleFlag) YScale = Scale; 
 
    if (XScale > MAX_SCALE) { 
	sprintf(s, "XScale too big, maximum scale selected instead (%d).", 
								MAX_SCALE); 
	GIF_MESSAGE(s); 
	XScale = MAX_SCALE; 
    } 
    if (YScale > MAX_SCALE) { 
	sprintf(s, "YScale too big, maximum scale selected instead (%d).", 
								MAX_SCALE); 
	GIF_MESSAGE(s); 
	YScale = MAX_SCALE; 
    } 
 
    if (NumFiles == 1) { 
	if ((GifFileIn = DGifOpenFileName(*FileName)) == NULL) 
	    QuitGifError(GifFileIn, GifFileOut); 
    } 
    else { 
	/* Use the stdin instead: */ 
	if ((GifFileIn = DGifOpenFileHandle(0)) == NULL) 
	    QuitGifError(GifFileIn, GifFileOut); 
    } 
    BackGroundColor = GifFileIn -> SBackGroundColor; 
 
    /* If size was specified, it is used to derive the scale: */ 
    if (SizeFlag) { 
	XScale = XSize / ((double) GifFileIn -> SWidth); 
	YScale = YSize / ((double) GifFileIn -> SHeight); 
    } 
    else 
    { 
	XSize = (int) (GifFileIn -> SWidth * XScale + 0.5); 
	YSize = (int) (GifFileIn -> SHeight * YScale + 0.5); 
    } 
 
    /* As at this time we know the Screen size of the input gif file, and as */ 
    /* all image(s) in file must be less/equal to it, we can allocate the    */ 
    /* scan lines for the input file, and output file. The number of lines   */ 
    /* to allocate for each is set by ScaleDown & XScale & YScale:	     */ 
    LineOut = (GifRowType) malloc(XSize * sizeof(GifPixelType)); 
    LineIn = (GifRowType) malloc(GifFileIn -> SWidth * sizeof(GifPixelType)); 
 
    /* Open stdout for the output file: */ 
    if ((GifFileOut = EGifOpenFileHandle(1)) == NULL) 
	QuitGifError(GifFileIn, GifFileOut); 
 
    /* And dump out its new scaled screen information: */ 
    if (EGifPutScreenDesc(GifFileOut, XSize, YSize, 
	GifFileIn -> SColorResolution, GifFileIn -> SBackGroundColor, 
	GifFileIn -> SBitsPerPixel, GifFileIn -> SColorMap) == GIF_ERROR) 
	QuitGifError(GifFileIn, GifFileOut); 
 
    /* Scan the content of the GIF file and load the image(s) in: */ 
    do { 
	if (DGifGetRecordType(GifFileIn, &RecordType) == GIF_ERROR) 
	    QuitGifError(GifFileIn, GifFileOut); 
 
	switch (RecordType) { 
	    case IMAGE_DESC_RECORD_TYPE: 
		if (DGifGetImageDesc(GifFileIn) == GIF_ERROR) 
		    QuitGifError(GifFileIn, GifFileOut); 
		/* Put the image descriptor to out file: */ 
		l = (int) (GifFileIn -> ILeft * XScale + 0.5); 
		w = (int) (GifFileIn -> IWidth * XScale + 0.5); 
		t = (int) (GifFileIn -> ITop * YScale + 0.5); 
		h = (int) (GifFileIn -> IHeight * YScale + 0.5); 
		if (l < 0) l = 0; 
		if (t < 0) t = 0; 
		if (l + w > XSize) w = XSize - l; 
		if (t + h > YSize) h = YSize - t; 
 
		if (EGifPutImageDesc(GifFileOut, l, t, w, h, 
		    GifFileIn -> IInterlace, GifFileIn -> IBitsPerPixel, 
		    GifFileIn -> IColorMap) == GIF_ERROR) 
		    QuitGifError(GifFileIn, GifFileOut); 
 
		if (GifFileIn -> IInterlace) { 
		    GIF_EXIT("Cannt resize interlaced images - use GifInter first."); 
		} 
		else { 
		    GifQprintf("\n%s: Image %d at (%d, %d) [%dx%d]:     ", 
			PROGRAM_NAME, ++ImageNum, 
			GifFileOut -> ILeft, GifFileOut -> ITop, 
			GifFileOut -> IWidth, GifFileOut -> IHeight); 
 
		    for (i = GifFileIn -> IHeight, y = 0.0, last_iy = -1; 
			 i-- > 0; 
			 y += YScale) { 
			if (DGifGetLine(GifFileIn, LineIn, 
					GifFileIn -> IWidth) == GIF_ERROR) 
			    QuitGifError(GifFileIn, GifFileOut); 
 
			iy = (int) y; 
			if (last_iy < iy && last_iy < YSize) { 
			    ResizeLine(LineIn, LineOut, 
				       GifFileIn -> IWidth, GifFileOut -> IWidth); 
 
			    for (; 
				 last_iy < iy && last_iy < GifFileOut -> IHeight - 1; 
				 last_iy++) { 
				GifQprintf("\b\b\b\b%-4d", last_iy + 1); 
				if (EGifPutLine(GifFileOut, LineOut, 
						GifFileOut -> IWidth) == 
								    GIF_ERROR) 
				    QuitGifError(GifFileIn, GifFileOut); 
			    } 
			} 
		    } 
 
		    /* If scale is not dividable - dump last lines: */ 
		    while (++last_iy < GifFileOut -> IHeight) { 
			GifQprintf("\b\b\b\b%-4d", last_iy); 
			if (EGifPutLine(GifFileOut, LineOut, 
					GifFileOut -> IWidth) == GIF_ERROR) 
			    QuitGifError(GifFileIn, GifFileOut); 
		    } 
		} 
		break; 
	    case EXTENSION_RECORD_TYPE: 
		/* Skip any extension blocks in file: */ 
		if (DGifGetExtension(GifFileIn, &ExtCode, &Extension) == GIF_ERROR) 
		    QuitGifError(GifFileIn, GifFileOut); 
		if (EGifPutExtension(GifFileOut, ExtCode, Extension[0], 
							Extension) == GIF_ERROR) 
		    QuitGifError(GifFileIn, GifFileOut); 
 
		/* No support to more than one extension blocks, so discard: */ 
		while (Extension != NULL) { 
		    if (DGifGetExtensionNext(GifFileIn, &Extension) == GIF_ERROR) 
			QuitGifError(GifFileIn, GifFileOut); 
		} 
		break; 
	    case TERMINATE_RECORD_TYPE: 
		break; 
	    default:		    /* Should be traps by DGifGetRecordType. */ 
		break; 
	} 
    } 
    while (RecordType != TERMINATE_RECORD_TYPE); 
 
    if (DGifCloseFile(GifFileIn) == GIF_ERROR) 
	QuitGifError(GifFileIn, GifFileOut); 
    if (EGifCloseFile(GifFileOut) == GIF_ERROR) 
	QuitGifError(GifFileIn, GifFileOut); 
 
    free(LineOut); 
    free(LineIn); 
} 
 
/****************************************************************************** 
* Line resizing routine - scale given lines as follows:			      * 
* Scale (by pixel duplication/elimination) from InLineLen to OutLineLen.      * 
******************************************************************************/ 
static void ResizeLine(GifRowType LineIn, GifRowType LineOut, 
		      int InLineLen, int OutLineLen) 
{ 
    int i, ix, last_ix; 
    double x; 
 
    OutLineLen--; 
 
    for (i = InLineLen, x = 0.0, last_ix = -1; 
	 i-- > 0; 
	 x += XScale, LineIn++) 
    { 
	ix = (int) x; 
    	for (; last_ix < ix && last_ix < OutLineLen; last_ix++) 
	    *LineOut++ = *LineIn; 
    } 
 
    /* Make sure the line is complete. */ 
    for (LineIn--; last_ix < OutLineLen; last_ix++) 
	*LineOut++ = *LineIn; 
} 
 
/****************************************************************************** 
* Close both input and output file (if open), and exit.			      * 
******************************************************************************/ 
static void QuitGifError(GifFileType *GifFileIn, GifFileType *GifFileOut) 
{ 
    PrintGifError(); 
    if (GifFileIn != NULL) DGifCloseFile(GifFileIn); 
    if (GifFileOut != NULL) EGifCloseFile(GifFileOut); 
    exit(1); 
}