Esempio n. 1
0
/******************************************************************************
 Put the image code in compressed form. This routine can be called if the
 information needed to be piped out as is. Obviously this is much faster
 than decoding and encoding again. This routine should be followed by calls
 to EGifPutCodeNext, until NULL block is given.
 The block should NOT be freed by the user (not dynamically allocated).
******************************************************************************/
int
EGifPutCode(GifFileType *GifFile, int CodeSize, const GifByteType *CodeBlock)
{
    GifFilePrivateType *Private = (GifFilePrivateType *)GifFile->Private;

    if (!IS_WRITEABLE(Private)) {
        /* This file was NOT open for writing: */
        GifFile->Error = E_GIF_ERR_NOT_WRITEABLE;
        return GIF_ERROR;
    }

    /* No need to dump code size as Compression set up does any for us: */
    /* 
     * Buf = CodeSize;
     * if (InternalWrite(GifFile, &Buf, 1) != 1) {
     *      GifFile->Error = E_GIF_ERR_WRITE_FAILED;
     *      return GIF_ERROR;
     * }
     */

    return EGifPutCodeNext(GifFile, CodeBlock);
}
Esempio n. 2
0
/******************************************************************************
* Interpret the command line and scan the given GIF file.		      *
******************************************************************************/
int main(int argc, char **argv)
{
    int	Error, NumFiles, ExtCode, CodeSize, ImageNum = 0,
	ImageNFlag = FALSE, ImageN, HelpFlag = FALSE, HasGIFOutput;
    GifRecordType RecordType;
    GifByteType *Extension, *CodeBlock;
    char **FileName = NULL, *ColorFileName, *TranslateFileName;
    GifFileType *GifFileIn = NULL, *GifFileOut = NULL;

    if ((Error = GAGetArgs(argc, argv, CtrlStr, &GifQuietPrint, &SaveFlag, 
		&TranslateFlag, &TranslateFileName,
		&LoadFlag, &ColorFileName,
		&GammaFlag, &Gamma, &ImageNFlag, &ImageN,
		&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(EXIT_FAILURE);
    }

    if (HelpFlag) {
	fprintf(stderr, VersionStr);
	GAPrintHowTo(CtrlStr);
	exit(EXIT_SUCCESS);
    }

    if (SaveFlag + LoadFlag + GammaFlag + TranslateFlag > 1)
	GIF_EXIT("Can not handle more than one of -s -l, -t, or -g at the same time.");

    if (NumFiles == 1) {
	if ((GifFileIn = DGifOpenFileName(*FileName)) == NULL)
	    QuitGifError(GifFileIn, GifFileOut);
    }
    else {
	/* Use stdin instead: */
	if ((GifFileIn = DGifOpenFileHandle(0)) == NULL)
	    QuitGifError(GifFileIn, GifFileOut);
    }

    if (SaveFlag) {
	/* We are dumping out the color map as text file to stdout: */
	ColorFile = stdout;
    }
    else {
	if (TranslateFlag) {
	    /* We are loading new color map from specified file: */
	    if ((TranslateFile = fopen(TranslateFileName, "rt")) == NULL)
		GIF_EXIT("Failed to open specified color translation file.");
	}

	if (LoadFlag) {
	    /* We are loading new color map from specified file: */
	    if ((ColorFile = fopen(ColorFileName, "rt")) == NULL)
		GIF_EXIT("Failed to open specified color map file.");
	}
    }

    if ((HasGIFOutput = (LoadFlag || TranslateFlag || GammaFlag)) != 0) {
	/* Open stdout for GIF output file: */
	if ((GifFileOut = EGifOpenFileHandle(1)) == NULL)
	    QuitGifError(GifFileIn, GifFileOut);
    }

    if (!ImageNFlag) {
	/* We are suppose to modify the screen color map, so do it: */
	GifFileIn->SColorMap = ModifyColorMap(GifFileIn->SColorMap);
	if (!HasGIFOutput) {
	    /* We can quit here, as we have the color map: */
	    if (GifFileIn != NULL) DGifCloseFile(GifFileIn);
	    fclose(ColorFile);
	    exit(EXIT_SUCCESS);
	}
    }
    /* And dump out its new possible repositioned screen information: */
    if (HasGIFOutput)
	if (EGifPutScreenDesc(GifFileOut,
	    GifFileIn->SWidth, GifFileIn->SHeight,
	    GifFileIn->SColorResolution, GifFileIn->SBackGroundColor,
	    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);
		if ((++ImageNum == ImageN) && ImageNFlag) {
		    /* We are suppose to modify this image color map, do it: */
		    GifFileIn->SColorMap =ModifyColorMap(GifFileIn->SColorMap);
		    if (!HasGIFOutput) {
			/* We can quit here, as we have the color map: */
			if (GifFileIn != NULL) DGifCloseFile(GifFileIn);
			fclose(ColorFile);
			exit(EXIT_SUCCESS);
		    }
		}
		if (HasGIFOutput)
		    if (EGifPutImageDesc(GifFileOut,
			GifFileIn->Image.Left, GifFileIn->Image.Top,
			GifFileIn->Image.Width, GifFileIn->Image.Height,
			GifFileIn->Image.Interlace,
			GifFileIn->Image.ColorMap) == GIF_ERROR)
			QuitGifError(GifFileIn, GifFileOut);

		if (!TranslateFlag || (ImageNFlag && (ImageN != ImageNum)))
		{
		    /* Now read image itself in decoded form as we don't */
		    /* really care what we have there, and this is much  */
		    /* faster.						 */
		    if (DGifGetCode(GifFileIn, &CodeSize, &CodeBlock) == GIF_ERROR)
			QuitGifError(GifFileIn, GifFileOut);
		    if (HasGIFOutput)
			if (EGifPutCode(GifFileOut, CodeSize, CodeBlock) == GIF_ERROR)
			    QuitGifError(GifFileIn, GifFileOut);
		    while (CodeBlock != NULL) {
			if (DGifGetCodeNext(GifFileIn, &CodeBlock) == GIF_ERROR)
			    QuitGifError(GifFileIn, GifFileOut);
			if (HasGIFOutput)
			    if (EGifPutCodeNext(GifFileOut, CodeBlock) == GIF_ERROR)
				QuitGifError(GifFileIn, GifFileOut);
		    }
		}
		else	/* we need to mung pixels intices */
		{
		    int	i;
		    register GifPixelType *cp;

		    GifPixelType *Line
			= (GifPixelType *) malloc(GifFileIn->Image.Width *
						  sizeof(GifPixelType));
		    for (i = 0; i < GifFileIn->Image.Height; i++) {
			if (DGifGetLine(GifFileIn, Line,GifFileIn->Image.Width)
			    == GIF_ERROR) {
			    QuitGifError(GifFileIn, GifFileOut);
			}

			/* translation step goes here */
			for (cp = Line; cp < Line+GifFileIn->Image.Width; cp++)
			    *cp = Translation[*cp];

			if (EGifPutLine(GifFileOut,
					Line, GifFileIn->Image.Width)
			    == GIF_ERROR) {
			    QuitGifError(GifFileIn, GifFileOut);
			}
		    }
		    free((char *) Line);
		}
		break;
	    case EXTENSION_RECORD_TYPE:
		/* Skip any extension blocks in file: */
		if (DGifGetExtension(GifFileIn, &ExtCode, &Extension) == GIF_ERROR)
		    QuitGifError(GifFileIn, GifFileOut);
		if (HasGIFOutput)
		    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 (HasGIFOutput)
	if (EGifCloseFile(GifFileOut) == GIF_ERROR)
	    QuitGifError(GifFileIn, GifFileOut);

    return 0;
}
Esempio n. 3
0
/******************************************************************************
 Main sequence
******************************************************************************/
int main(int argc, char **argv)
{
    GifFileType *GifFileIn = NULL, *GifFileOut = NULL;
    GifRecordType RecordType;
    int CodeSize, ExtCode, ErrorCode;
    GifByteType *CodeBlock, *Extension;

    /*
     * Command-line processing goes here.
     */

    /* Use stdin as input (note this also read screen descriptor in: */
    if ((GifFileIn = DGifOpenFileHandle(0, &ErrorCode)) == NULL) {
	PrintGifError(ErrorCode);
	exit(EXIT_FAILURE);
    }

    /* Use the stdout as output: */
    if ((GifFileOut = EGifOpenFileHandle(1, &ErrorCode)) == NULL) {
	PrintGifError(ErrorCode);
	exit(EXIT_FAILURE);
    }

    /* And dump out its screen information: */
    if (EGifPutScreenDesc(GifFileOut,
	GifFileIn->SWidth, GifFileIn->SHeight,
	GifFileIn->SColorResolution, GifFileIn->SBackGroundColor,
	GifFileIn->SColorMap) == GIF_ERROR)
	QuitGifError(GifFileIn, GifFileOut);

    /* Scan the content of the input 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 image descriptor to out file: */
		if (EGifPutImageDesc(GifFileOut,
		    GifFileIn->Image.Left, GifFileIn->Image.Top,
		    GifFileIn->Image.Width, GifFileIn->Image.Height,
		    GifFileIn->Image.Interlace,
		    GifFileIn->Image.ColorMap) == GIF_ERROR)
		    QuitGifError(GifFileIn, GifFileOut);

		/* Now read image itself in decoded form as we dont really   */
		/* care what we have there, and this is much faster.	     */
		if (DGifGetCode(GifFileIn, &CodeSize, &CodeBlock) == GIF_ERROR ||
		    EGifPutCode(GifFileOut, CodeSize, CodeBlock) == GIF_ERROR)
		    QuitGifError(GifFileIn, GifFileOut);
		while (CodeBlock != NULL) {
		    if (DGifGetCodeNext(GifFileIn, &CodeBlock) == GIF_ERROR ||
			EGifPutCodeNext(GifFileOut, CodeBlock) == GIF_ERROR)
		    QuitGifError(GifFileIn, GifFileOut);
		}
		break;
	    case EXTENSION_RECORD_TYPE:
		/* pass through extension records */
		if (DGifGetExtension(GifFileIn, &ExtCode, &Extension) == GIF_ERROR)
		    QuitGifError(GifFileIn, GifFileOut);
		if (EGifPutExtensionLeader(GifFileOut, ExtCode) == GIF_ERROR)
		    QuitGifError(GifFileIn, GifFileOut);
		if (EGifPutExtensionBlock(GifFileOut, 
					  Extension[0],
					  Extension + 1) == GIF_ERROR)
		    QuitGifError(GifFileIn, GifFileOut);
		while (Extension != NULL) {
		    if (DGifGetExtensionNext(GifFileIn, &Extension)==GIF_ERROR)
			QuitGifError(GifFileIn, GifFileOut);
		    if (Extension != NULL)
			if (EGifPutExtensionBlock(GifFileOut, 
						  Extension[0],
						  Extension + 1) == GIF_ERROR)
			    QuitGifError(GifFileIn, GifFileOut);
		}
		if (EGifPutExtensionTrailer(GifFileOut) == GIF_ERROR)
		    QuitGifError(GifFileIn, GifFileOut);
		break;
	    case TERMINATE_RECORD_TYPE:
		break;
	    default:	     /* Should be trapped by DGifGetRecordType */
		break;
	}
    }
    while (RecordType != TERMINATE_RECORD_TYPE);

    if (DGifCloseFile(GifFileIn, &ErrorCode) == GIF_ERROR)
    {
	PrintGifError(ErrorCode);
	if (GifFileIn != NULL) {
	    EGifCloseFile(GifFileIn, NULL);
	}
	exit(EXIT_FAILURE);
    }
    if (EGifCloseFile(GifFileOut, &ErrorCode) == GIF_ERROR)
    {
	PrintGifError(ErrorCode);
	if (GifFileOut != NULL) {
	    EGifCloseFile(GifFileOut, NULL);
	}
	exit(EXIT_FAILURE);
    }

    return 0;
}
Esempio n. 4
0
/******************************************************************************
* Perform the disassembly operation - take one input files into few output.   *
******************************************************************************/
static int DoDisassemblyNum(const char *InFileName, char *OutFileName, int FileNum)
{
    int	ExtCode, CodeSize, FileEmpty;
    GifRecordType RecordType;
    char CrntFileName[80], *p;
    GifByteType *Extension, *CodeBlock;
    GifFileType *GifFileIn = NULL, *GifFileOut = NULL;
	int ErrorCode;

    /* If name has type postfix, strip it out, and make sure name is less    */
    /* or equal to 6 chars, so we will have 2 chars in name for numbers.     */
    //strupr(OutFileName);		      /* Make sure all is upper case */
	#if 0
	printf("OutFileName : %s\n", OutFileName);
	if ((p = strrchr(OutFileName, '.')) != NULL && strlen(p) <= 4) p[0] = 0;
    if ((p = strrchr(OutFileName, '/')) != NULL ||
	(p = strrchr(OutFileName, '\\')) != NULL ||
	(p = strrchr(OutFileName, ':')) != NULL) {
	if (strlen(p) > 7) p[7] = 0;   /* p includes the '/', '\\', ':' char */
    }
    else {
	/* Only name is given for current directory: */
	//if (strlen(OutFileName) > 6) OutFileName[6] = 0;
    }
	printf("OutFileName : %s\n", OutFileName);
	#endif

    /* Open input file: */
    if (InFileName != NULL) {
	if ((GifFileIn = DGifOpenFileName(InFileName, &ErrorCode)) == NULL)
	    return QuitGifError(GifFileIn, GifFileOut);
    }
    else {
	/* Use the stdin instead: */
	if ((GifFileIn = DGifOpenFileHandle(0, &ErrorCode)) == NULL)
	    return QuitGifError(GifFileIn, GifFileOut);
    }

    /* Scan the content of GIF file and dump image(s) to seperate file(s): */
	//sprintf(CrntFileName, "%s_%02d.gif", OutFileName, FileNum);
	sprintf(CrntFileName, "%s", OutFileName);
	if ((GifFileOut = EGifOpenFileName(CrntFileName, TRUE, &ErrorCode)) == NULL)
	    return QuitGifError(GifFileIn, GifFileOut);
	FileEmpty = TRUE;

	/* And dump out its exactly same screen information: */
	if (EGifPutScreenDesc(GifFileOut,
	    GifFileIn->SWidth, GifFileIn->SHeight,
	    GifFileIn->SColorResolution, GifFileIn->SBackGroundColor,
	    GifFileIn->SColorMap) == GIF_ERROR)
	    return QuitGifError(GifFileIn, GifFileOut);

	do {
	    if (DGifGetRecordType(GifFileIn, &RecordType) == GIF_ERROR)
			return QuitGifError(GifFileIn, GifFileOut);

	    switch (RecordType) {
		case IMAGE_DESC_RECORD_TYPE:
		    FileEmpty = FALSE;
		    if (DGifGetImageDesc(GifFileIn) == GIF_ERROR)
				return QuitGifError(GifFileIn, GifFileOut);
		    /* Put same image descriptor to out file: */
		    if (EGifPutImageDesc(GifFileOut,
			GifFileIn->Image.Left, GifFileIn->Image.Top,
			GifFileIn->Image.Width, GifFileIn->Image.Height,
			GifFileIn->Image.Interlace,
			GifFileIn->Image.ColorMap) == GIF_ERROR)
				return QuitGifError(GifFileIn, GifFileOut);

		    /* Now read image itself in decoded form as we dont      */
		    /* really care what is there, and this is much faster.   */
		    if (DGifGetCode(GifFileIn, &CodeSize, &CodeBlock) == GIF_ERROR
		     || EGifPutCode(GifFileOut, CodeSize, CodeBlock) == GIF_ERROR)
				return QuitGifError(GifFileIn, GifFileOut);
		    while (CodeBlock != NULL)
			if (DGifGetCodeNext(GifFileIn, &CodeBlock) == GIF_ERROR ||
			    EGifPutCodeNext(GifFileOut, CodeBlock) == GIF_ERROR)
				return QuitGifError(GifFileIn, GifFileOut);
		    break;
		case EXTENSION_RECORD_TYPE:
		    FileEmpty = FALSE;
		    /* Skip any extension blocks in file: */
		    if (DGifGetExtension(GifFileIn, &ExtCode, &Extension)
			== GIF_ERROR)
				return QuitGifError(GifFileIn, GifFileOut);
		    if (EGifPutExtension(GifFileOut, ExtCode, Extension[0],
							Extension) == GIF_ERROR)
				return QuitGifError(GifFileIn, GifFileOut);

		    /* No support to more than one extension blocks, discard */
		    while (Extension != NULL)
			if (DGifGetExtensionNext(GifFileIn, &Extension)
			    == GIF_ERROR)
			    return QuitGifError(GifFileIn, GifFileOut);
		    break;
		case TERMINATE_RECORD_TYPE:
		    break;
		default:	     /* Should be traps by DGifGetRecordType */
		    break;
	    }
	}
	while (RecordType != IMAGE_DESC_RECORD_TYPE &&
	       RecordType != TERMINATE_RECORD_TYPE);

	if (EGifCloseFile(GifFileOut, &ErrorCode) == GIF_ERROR)
	    return QuitGifError(GifFileIn, GifFileOut);
	if (FileEmpty) {
	    /* Might happen on last file - delete it if so: */
	    unlink(CrntFileName);
	}

    if (DGifCloseFile(GifFileIn, &ErrorCode) == GIF_ERROR)
		return QuitGifError(GifFileIn, GifFileOut);
}
Esempio n. 5
0
/******************************************************************************
* Perform the assembly operation - take few input files into one output.      *
******************************************************************************/
static void DoAssembly(int NumFiles, char **FileNames)
{
    int	i, ExtCode, CodeSize;
    GifRecordType RecordType;
    GifByteType *Extension, *CodeBlock;
    GifFileType *GifFileIn = NULL, *GifFileOut = NULL;

    /* Open stdout for the output file: */
    if ((GifFileOut = EGifOpenFileHandle(1)) == NULL)
	QuitGifError(GifFileIn, GifFileOut);

    /* Scan the content of the GIF file and load the image(s) in: */
    for (i = 0; i < NumFiles; i++) {
	if ((GifFileIn = DGifOpenFileName(FileNames[i])) == NULL)
	    QuitGifError(GifFileIn, GifFileOut);

	/* And dump out screen descriptor iff its first image.	*/
	if (i == 0)
	    if (EGifPutScreenDesc(GifFileOut,
		GifFileIn -> SWidth, GifFileIn -> SHeight,
		GifFileIn -> SColorResolution, GifFileIn -> SBackGroundColor,
		GifFileIn -> SBitsPerPixel, GifFileIn -> SColorMap) == GIF_ERROR)
		QuitGifError(GifFileIn, GifFileOut);

	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 image descriptor to out file: */
		    if (EGifPutImageDesc(GifFileOut,
			GifFileIn -> ILeft, GifFileIn -> ITop,
			GifFileIn -> IWidth, GifFileIn -> IHeight,
			GifFileIn -> IInterlace, GifFileIn -> IBitsPerPixel,
			GifFileIn -> IColorMap) == GIF_ERROR)
			QuitGifError(GifFileIn, GifFileOut);

		    /* Now read image itself in decoded form as we dont      */
		    /* dont care what is there, and this is much faster.     */
		    if (DGifGetCode(GifFileIn, &CodeSize, &CodeBlock) == GIF_ERROR
		     || EGifPutCode(GifFileOut, CodeSize, CodeBlock) == GIF_ERROR)
			QuitGifError(GifFileIn, GifFileOut);
		    while (CodeBlock != NULL)
			if (DGifGetCodeNext(GifFileIn, &CodeBlock) == GIF_ERROR ||
			    EGifPutCodeNext(GifFileOut, CodeBlock) == 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, 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);
}
Esempio n. 6
0
/******************************************************************************
* Interpret the command line and scan the given GIF file.		      *
******************************************************************************/
int main(int argc, char **argv)
{
    int	i, Error, NumFiles, ExtCode, CodeSize, ImageNum = 0,
	ImageFlag = FALSE, ImageNFlag = FALSE, ImageN, ImageX1, ImageY1,
	ImageX2, ImageY2, ImageWidth, ImageDepth,
	Complement = FALSE, HelpFlag = FALSE;
    GifRecordType RecordType;
    GifByteType *Extension, *CodeBlock;
    char **FileName = NULL;
    GifRowType Line;
    GifFileType *GifFileIn = NULL, *GifFileOut = NULL;

    /* Same image dimension vars for both Image & ImageN as only one allowed.*/
    if ((Error = GAGetArgs(argc, argv, CtrlStr, &GifQuietPrint, &Complement,
		&ImageFlag, &ImageX1, &ImageY1, &ImageX2, &ImageY2,
		&ImageNFlag, &ImageN, &ImageX1, &ImageY1, &ImageX2, &ImageY2,
		&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(EXIT_FAILURE);
    }

    if (HelpFlag) {
	fprintf(stderr, VersionStr);
	GAPrintHowTo(CtrlStr);
	exit(EXIT_SUCCESS);
    }

    /* Test to make sure exactly one of ImageFlag & ImageNFlag is set: */
    if ((ImageFlag && ImageNFlag) || (!ImageFlag && !ImageNFlag)) {
	GIF_MESSAGE("Exactly one of [-i ...] && [-n ...] please.");
	GAPrintHowTo(CtrlStr);
	exit(EXIT_FAILURE);
    }
    if (ImageFlag) ImageN = 1;		    /* Its first image we are after. */

    /* Make sure the first coordinates of clipping box are smaller: */
    if (ImageX1 > ImageX2) {
	i = ImageX1;
	ImageX1 = ImageX2;
	ImageX2 = i;
    }
    if (ImageY1 > ImageY2) {
	i = ImageX1;
	ImageY1 = ImageY2;
	ImageY2 = i;
    }

    if (NumFiles == 1) {
	if ((GifFileIn = DGifOpenFileName(*FileName)) == NULL)
	    QuitGifError(GifFileIn, GifFileOut);
    }
    else {
	/* Use the stdin instead: */
	if ((GifFileIn = DGifOpenFileHandle(0)) == NULL)
	    QuitGifError(GifFileIn, GifFileOut);
    }

    /* Open stdout for the output file: */
    if ((GifFileOut = EGifOpenFileHandle(1)) == NULL)
	QuitGifError(GifFileIn, GifFileOut);

    /* Width and depth of clipped image. */
    if (!Complement)
	ImageWidth = ImageX2 - ImageX1 + 1;
    else
	ImageWidth = GifFileIn->SWidth
	    - (ImageX2 != ImageX1) * (ImageX2 - ImageX1 + 1);
    if (!Complement)
	ImageDepth = ImageY2 - ImageY1 + 1;
    else
	ImageDepth = GifFileIn->SHeight
	    - (ImageY2 != ImageY1) * (ImageY2 - ImageY1 + 1);

    /* And dump out exactly same screen information: */
    if (EGifPutScreenDesc(GifFileOut,
	GifFileIn->SWidth, GifFileIn->SHeight,
	GifFileIn->SColorResolution, GifFileIn->SBackGroundColor,
	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);
		if (++ImageNum == ImageN) {
		    /* We can handle only non interlaced images here: */
		    if (GifFileIn->Image.Interlace)
			GIF_EXIT("Image to clip is interlaced - use GifInter first.");

		    /* This is the image we should clip - test sizes and     */
		    /* dump out new clipped screen descriptor if o.k.	     */
		    if (GifFileIn->Image.Width <= ImageX2 ||
			GifFileIn->Image.Height <= ImageY2)
			GIF_EXIT("Image is smaller than given clip dimensions.");

		    /* Put the image descriptor to out file: */
		    if (EGifPutImageDesc(GifFileOut,
			GifFileIn->Image.Left, GifFileIn->Image.Top,
			ImageWidth, ImageDepth,
			FALSE, GifFileIn->Image.ColorMap) == GIF_ERROR)
			QuitGifError(GifFileIn, GifFileOut);

		    /* o.k. - read the image and clip it: */
		    Line = (GifRowType) malloc(GifFileIn->Image.Width *
							sizeof(GifPixelType));
		    GifQprintf("\n%s: Image %d at (%d, %d) [%dx%d]:     ",
			PROGRAM_NAME, ImageNum,
			GifFileIn->Image.Left, GifFileIn->Image.Top,
			GifFileIn->Image.Width, GifFileIn->Image.Height);

		    /* Skip lines below ImageY1: */
		    for (i = 0; i < ImageY1; i++) {
			if (DGifGetLine(GifFileIn, Line, GifFileIn->Image.Width)
			    == GIF_ERROR)
			    QuitGifError(GifFileIn, GifFileOut);

			if (Complement) {
			    if (ImageX1 == ImageX2) {
				/* don't remove any vertical band */
				if (EGifPutLine(GifFileOut, Line,
						ImageWidth) == GIF_ERROR)
				    QuitGifError(GifFileIn, GifFileOut);
			    }
			    else
			    {
				if (EGifPutLine(GifFileOut, Line,
						ImageX1) == GIF_ERROR)
				    QuitGifError(GifFileIn, GifFileOut);

				if (EGifPutLine(GifFileOut,
						&Line[ImageX2 + 1],
						GifFileIn->SWidth - (ImageX2 + 1)
						) == GIF_ERROR)
				    QuitGifError(GifFileIn, GifFileOut);
			    }
			}

			GifQprintf("\b\b\b\b%-4d", i);
		    }

		    /* Clip the lines from ImageY1 to ImageY2 (to X1 - X2): */
		    for (i = ImageY1; i <= ImageY2; i++) {
			if (DGifGetLine(GifFileIn, Line, GifFileIn->Image.Width)
			    == GIF_ERROR)
			    QuitGifError(GifFileIn, GifFileOut);

			if (!Complement)
			    if (EGifPutLine(GifFileOut, &Line[ImageX1],
					    ImageWidth) == GIF_ERROR)
				QuitGifError(GifFileIn, GifFileOut);

			GifQprintf("\b\b\b\b%-4d", i);
		    }

		    /* Skip lines above ImageY2: */
		    for (i = ImageY2 + 1; i < GifFileIn->Image.Height; i++) {
			if (DGifGetLine(GifFileIn, Line, GifFileIn->Image.Width)
			    == GIF_ERROR)
			    QuitGifError(GifFileIn, GifFileOut);

			if (Complement) {
			    if (ImageX1 == ImageX2) {
				/* don't remove any vertical band */
				if (EGifPutLine(GifFileOut, Line,
						ImageWidth) == GIF_ERROR)
				    QuitGifError(GifFileIn, GifFileOut);
			    }
			    else
			    {
				if (EGifPutLine(GifFileOut, Line,
						ImageX1) == GIF_ERROR)
				    QuitGifError(GifFileIn, GifFileOut);

				if (EGifPutLine(GifFileOut,
						&Line[ImageX2 + 1],
						GifFileIn->SWidth - (ImageX2 + 1)
						) == GIF_ERROR)
				    QuitGifError(GifFileIn, GifFileOut);
			    }
			}

			GifQprintf("\b\b\b\b%-4d", i);
		    }

		    free((char *) Line);
		}
		else {
		    /* Copy the image as is (we dont modify this one): */
		    if (EGifPutImageDesc(GifFileOut,
			GifFileIn->Image.Left, GifFileIn->Image.Top,
			GifFileIn->Image.Width, GifFileIn->Image.Height,
			GifFileIn->Image.Interlace,
			GifFileIn->Image.ColorMap) == GIF_ERROR)
			QuitGifError(GifFileIn, GifFileOut);

		    /* Now read image itself in decoded form as we dont      */
		    /* really care what is there, and this is much faster.   */
		    if (DGifGetCode(GifFileIn, &CodeSize, &CodeBlock) == GIF_ERROR
		     || EGifPutCode(GifFileOut, CodeSize, CodeBlock) == GIF_ERROR)
			QuitGifError(GifFileIn, GifFileOut);
		    while (CodeBlock != NULL)
			if (DGifGetCodeNext(GifFileIn, &CodeBlock) == GIF_ERROR ||
			    EGifPutCodeNext(GifFileOut, CodeBlock) == 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);

    return 0;
}