gifclrmp.c - platform/external/giflib - Git at Google

 /*****************************************************************************

 gifclrmap - extract colormaps from GIF images

 SPDX-License-Identifier: MIT

 *****************************************************************************/

 #include <assert.h>
 #include <ctype.h>
 #include <math.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>

 #include "getarg.h"
 #include "gif_lib.h"

 #define PROGRAM_NAME "gifclrmp"

 static char *VersionStr = PROGRAM_NAME VERSION_COOKIE
     "	Gershon Elber,	" __DATE__ ",   " __TIME__ "\n"
     "(C) Copyright 1989 Gershon Elber.\n";
 static char *CtrlStr =
     PROGRAM_NAME " v%- s%- t%-TranslationFile!s l%-ColorMapFile!s g%-Gamma!F "
                  "i%-Image#!d h%- GifFile!*s";

 static bool SaveFlag = false, TranslateFlag = false, LoadFlag = false,
             GammaFlag = false;
 static double Gamma = 1.0;
 static FILE *ColorFile = NULL;
 FILE *TranslateFile = NULL;
 static GifPixelType Translation[256];

 static ColorMapObject *ModifyColorMap(ColorMapObject *ColorMap);
 static void QuitGifError(GifFileType *GifFileIn, GifFileType *GifFileOut);

 /******************************************************************************
  Interpret the command line and scan the given GIF file.
 ******************************************************************************/
 int main(int argc, char **argv) {
 	int NumFiles, ExtCode, CodeSize, ImageNum = 0, ImageN, HasGIFOutput,
 	                                 ErrorCode;
 	bool Error, ImageNFlag = false, HelpFlag = false, GifNoisyPrint = false;
 	GifRecordType RecordType;
 	GifByteType *Extension, *CodeBlock;
 	char **FileName = NULL, *ColorFileName, *TranslateFileName;
 	GifFileType *GifFileIn = NULL, *GifFileOut = NULL;

 	if ((Error = GAGetArgs(argc, argv, CtrlStr, &GifNoisyPrint, &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) {
 		(void)fprintf(stderr, VersionStr, GIFLIB_MAJOR, GIFLIB_MINOR);
 		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.");
 	}

 	/* Default action is to dump colormaps */
 	if (!SaveFlag && !LoadFlag && !GammaFlag && !TranslateFlag) {
 		SaveFlag = true;
 	}

 	if (NumFiles == 1) {
 		if ((GifFileIn = DGifOpenFileName(*FileName, &ErrorCode)) ==
 		    NULL) {
 			PrintGifError(ErrorCode);
 			exit(EXIT_FAILURE);
 		}
 	} else {
 		/* Use stdin instead: */
 		if ((GifFileIn = DGifOpenFileHandle(0, &ErrorCode)) == NULL) {
 			PrintGifError(ErrorCode);
 			exit(EXIT_FAILURE);
 		}
 	}

 	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, &ErrorCode)) == NULL) {
 			PrintGifError(ErrorCode);
 			exit(EXIT_FAILURE);
 		}
 	}

 	if (!ImageNFlag) {
 		/* We are supposed to modify the screen color map, so do it: */
 		if (!GifFileIn->SColorMap) {
 			GIF_EXIT("No colormap to modify");
 		}
 		GifFileIn->SColorMap = ModifyColorMap(GifFileIn->SColorMap);
 		if (!HasGIFOutput) {
 			/* We can quit here, as we have the color map: */
 			DGifCloseFile(GifFileIn, NULL);
 			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: */
 					DGifCloseFile(GifFileIn, NULL);
 					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:
 			assert(GifFileOut != NULL); /* might pacify Coverity */
 			/* pass through extension records */
 			if (DGifGetExtension(GifFileIn, &ExtCode, &Extension) ==
 			    GIF_ERROR) {
 				QuitGifError(GifFileIn, GifFileOut);
 			}
 			if (Extension == NULL) {
 				break;
 			}
 			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);
 		exit(EXIT_FAILURE);
 	}
 	if (HasGIFOutput) {
 		if (EGifCloseFile(GifFileOut, &ErrorCode) == GIF_ERROR) {
 			PrintGifError(ErrorCode);
 			exit(EXIT_FAILURE);
 		}
 	}

 	return 0;
 }

 /******************************************************************************
  Modify the given colormap according to global variables setting.
 ******************************************************************************/
 static ColorMapObject *ModifyColorMap(ColorMapObject *ColorMap) {
 	int i, Dummy, Red, Green, Blue;

 	if (SaveFlag) {
 		/* Save this color map to ColorFile: */
 		for (i = 0; i < ColorMap->ColorCount; i++) {
 			fprintf(ColorFile, "%3d %3d %3d %3d\n", i,
 			        ColorMap->Colors[i].Red,
 			        ColorMap->Colors[i].Green,
 			        ColorMap->Colors[i].Blue);
 		}
 		return (ColorMap);
 	} else if (LoadFlag) {
 		/* Read the color map in ColorFile into this color map: */
 		for (i = 0; i < ColorMap->ColorCount; i++) {
 			if (feof(ColorFile)) {
 				GIF_EXIT("Color file to load color map from, "
 				         "too small.");
 			}
 			if (fscanf(ColorFile, "%3d %3d %3d %3d\n", &Dummy, &Red,
 			           &Green, &Blue) == 4) {
 				ColorMap->Colors[i].Red = Red;
 				ColorMap->Colors[i].Green = Green;
 				ColorMap->Colors[i].Blue = Blue;
 			}
 		}
 		return (ColorMap);
 	} else if (GammaFlag) {
 		/* Apply gamma correction to this color map: */
 		double Gamma1 = 1.0 / Gamma;
 		for (i = 0; i < ColorMap->ColorCount; i++) {
 			ColorMap->Colors[i].Red =
 			    ((int)(255 * pow(ColorMap->Colors[i].Red / 255.0,
 			                     Gamma1)));
 			ColorMap->Colors[i].Green =
 			    ((int)(255 * pow(ColorMap->Colors[i].Green / 255.0,
 			                     Gamma1)));
 			ColorMap->Colors[i].Blue =
 			    ((int)(255 * pow(ColorMap->Colors[i].Blue / 255.0,
 			                     Gamma1)));
 		}
 		return (ColorMap);
 	} else if (TranslateFlag) {
 		ColorMapObject *NewMap;
 		int Max = 0;

 		/* Read the translation table in TranslateFile: */
 		for (i = 0; i < ColorMap->ColorCount; i++) {
 			int tmp;
 			if (feof(TranslateFile)) {
 				GIF_EXIT("Color file to load color map from, "
 				         "too small.");
 			}
 			if (fscanf(TranslateFile, "%3d %3d\n", &Dummy, &tmp) ==
 			    2) {
 				Translation[i] = tmp & 0xff;
 				if (Translation[i] > Max) {
 					Max = Translation[i];
 				}
 			}
 		}

 		if ((NewMap = GifMakeMapObject(1 << GifBitSize(Max + 1),
 		                               NULL)) == NULL) {
 			GIF_EXIT("Out of memory while allocating color map!");
 		}

 		/* Apply the translation; we'll do it to the pixels, too */
 		for (i = 0; i < ColorMap->ColorCount; i++) {
 			NewMap->Colors[i] = ColorMap->Colors[Translation[i]];
 		}

 		return (NewMap);
 	} else {
 		GIF_EXIT("Nothing to do!");
 		return (ColorMap);
 	}
 }

 /******************************************************************************
  Close both input and output file (if open), and exit.
 ******************************************************************************/
 static void QuitGifError(GifFileType *GifFileIn, GifFileType *GifFileOut) {
 	if (GifFileIn != NULL) {
 		PrintGifError(GifFileIn->Error);
 		EGifCloseFile(GifFileIn, NULL);
 	}
 	if (GifFileOut != NULL) {
 		PrintGifError(GifFileOut->Error);
 		EGifCloseFile(GifFileOut, NULL);
 	}
 	exit(EXIT_FAILURE);
 }

 /* end */
	/*****************************************************************************

	gifclrmap - extract colormaps from GIF images

	SPDX-License-Identifier: MIT

	*****************************************************************************/

	#include <assert.h>
	#include <ctype.h>
	#include <math.h>
	#include <stdbool.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>

	#include "getarg.h"
	#include "gif_lib.h"

	#define PROGRAM_NAME "gifclrmp"

	static char *VersionStr = PROGRAM_NAME VERSION_COOKIE
	" Gershon Elber, " __DATE__ ", " __TIME__ "\n"
	"(C) Copyright 1989 Gershon Elber.\n";
	static char *CtrlStr =
	PROGRAM_NAME " v%- s%- t%-TranslationFile!s l%-ColorMapFile!s g%-Gamma!F "
	"i%-Image#!d h%- GifFile!*s";

	static bool SaveFlag = false, TranslateFlag = false, LoadFlag = false,
	GammaFlag = false;
	static double Gamma = 1.0;
	static FILE *ColorFile = NULL;
	FILE *TranslateFile = NULL;
	static GifPixelType Translation[256];

	static ColorMapObject ModifyColorMap(ColorMapObject ColorMap);
	static void QuitGifError(GifFileType GifFileIn, GifFileType GifFileOut);

	/******************************************************************************
	Interpret the command line and scan the given GIF file.
	******************************************************************************/
	int main(int argc, char **argv) {
	int NumFiles, ExtCode, CodeSize, ImageNum = 0, ImageN, HasGIFOutput,
	ErrorCode;
	bool Error, ImageNFlag = false, HelpFlag = false, GifNoisyPrint = false;
	GifRecordType RecordType;
	GifByteType Extension, CodeBlock;
	char *FileName = NULL, ColorFileName, *TranslateFileName;
	GifFileType GifFileIn = NULL, GifFileOut = NULL;

	if ((Error = GAGetArgs(argc, argv, CtrlStr, &GifNoisyPrint, &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) {
	(void)fprintf(stderr, VersionStr, GIFLIB_MAJOR, GIFLIB_MINOR);
	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.");
	}

	/* Default action is to dump colormaps */
	if (!SaveFlag && !LoadFlag && !GammaFlag && !TranslateFlag) {
	SaveFlag = true;
	}

	if (NumFiles == 1) {
	if ((GifFileIn = DGifOpenFileName(*FileName, &ErrorCode)) ==
	NULL) {
	PrintGifError(ErrorCode);
	exit(EXIT_FAILURE);
	}
	} else {
	/* Use stdin instead: */
	if ((GifFileIn = DGifOpenFileHandle(0, &ErrorCode)) == NULL) {
	PrintGifError(ErrorCode);
	exit(EXIT_FAILURE);
	}
	}

	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, &ErrorCode)) == NULL) {
	PrintGifError(ErrorCode);
	exit(EXIT_FAILURE);
	}
	}

	if (!ImageNFlag) {
	/* We are supposed to modify the screen color map, so do it: */
	if (!GifFileIn->SColorMap) {
	GIF_EXIT("No colormap to modify");
	}
	GifFileIn->SColorMap = ModifyColorMap(GifFileIn->SColorMap);
	if (!HasGIFOutput) {
	/* We can quit here, as we have the color map: */
	DGifCloseFile(GifFileIn, NULL);
	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: */
	DGifCloseFile(GifFileIn, NULL);
	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:
	assert(GifFileOut != NULL); /* might pacify Coverity */
	/* pass through extension records */
	if (DGifGetExtension(GifFileIn, &ExtCode, &Extension) ==
	GIF_ERROR) {
	QuitGifError(GifFileIn, GifFileOut);
	}
	if (Extension == NULL) {
	break;
	}
	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);
	exit(EXIT_FAILURE);
	}
	if (HasGIFOutput) {
	if (EGifCloseFile(GifFileOut, &ErrorCode) == GIF_ERROR) {
	PrintGifError(ErrorCode);
	exit(EXIT_FAILURE);
	}
	}

	return 0;
	}

	/******************************************************************************
	Modify the given colormap according to global variables setting.
	******************************************************************************/
	static ColorMapObject ModifyColorMap(ColorMapObject ColorMap) {
	int i, Dummy, Red, Green, Blue;

	if (SaveFlag) {
	/* Save this color map to ColorFile: */
	for (i = 0; i < ColorMap->ColorCount; i++) {
	fprintf(ColorFile, "%3d %3d %3d %3d\n", i,
	ColorMap->Colors[i].Red,
	ColorMap->Colors[i].Green,
	ColorMap->Colors[i].Blue);
	}
	return (ColorMap);
	} else if (LoadFlag) {
	/* Read the color map in ColorFile into this color map: */
	for (i = 0; i < ColorMap->ColorCount; i++) {
	if (feof(ColorFile)) {
	GIF_EXIT("Color file to load color map from, "
	"too small.");
	}
	if (fscanf(ColorFile, "%3d %3d %3d %3d\n", &Dummy, &Red,
	&Green, &Blue) == 4) {
	ColorMap->Colors[i].Red = Red;
	ColorMap->Colors[i].Green = Green;
	ColorMap->Colors[i].Blue = Blue;
	}
	}
	return (ColorMap);
	} else if (GammaFlag) {
	/* Apply gamma correction to this color map: */
	double Gamma1 = 1.0 / Gamma;
	for (i = 0; i < ColorMap->ColorCount; i++) {
	ColorMap->Colors[i].Red =
	((int)(255 * pow(ColorMap->Colors[i].Red / 255.0,
	Gamma1)));
	ColorMap->Colors[i].Green =
	((int)(255 * pow(ColorMap->Colors[i].Green / 255.0,
	Gamma1)));
	ColorMap->Colors[i].Blue =
	((int)(255 * pow(ColorMap->Colors[i].Blue / 255.0,
	Gamma1)));
	}
	return (ColorMap);
	} else if (TranslateFlag) {
	ColorMapObject *NewMap;
	int Max = 0;

	/* Read the translation table in TranslateFile: */
	for (i = 0; i < ColorMap->ColorCount; i++) {
	int tmp;
	if (feof(TranslateFile)) {
	GIF_EXIT("Color file to load color map from, "
	"too small.");
	}
	if (fscanf(TranslateFile, "%3d %3d\n", &Dummy, &tmp) ==
	2) {
	Translation[i] = tmp & 0xff;
	if (Translation[i] > Max) {
	Max = Translation[i];
	}
	}
	}

	if ((NewMap = GifMakeMapObject(1 << GifBitSize(Max + 1),
	NULL)) == NULL) {
	GIF_EXIT("Out of memory while allocating color map!");
	}

	/* Apply the translation; we'll do it to the pixels, too */
	for (i = 0; i < ColorMap->ColorCount; i++) {
	NewMap->Colors[i] = ColorMap->Colors[Translation[i]];
	}

	return (NewMap);
	} else {
	GIF_EXIT("Nothing to do!");
	return (ColorMap);
	}
	}

	/******************************************************************************
	Close both input and output file (if open), and exit.
	******************************************************************************/
	static void QuitGifError(GifFileType GifFileIn, GifFileType GifFileOut) {
	if (GifFileIn != NULL) {
	PrintGifError(GifFileIn->Error);
	EGifCloseFile(GifFileIn, NULL);
	}
	if (GifFileOut != NULL) {
	PrintGifError(GifFileOut->Error);
	EGifCloseFile(GifFileOut, NULL);
	}
	exit(EXIT_FAILURE);
	}

	/* end */