util/gifclrmp.c

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
main
ModifyColorMap
QuitGifError
/*****************************************************************************

gifclrmap - extract colormaps from GIF images

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

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

#include "gif_lib.h"
#include "getarg.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;
    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 (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 */
/* [<][>][^][v][top][bottom][index][help] */
root/util/gifclrmp.c

DEFINITIONS
