xtiff.c

tiff格式传真源码例子

    dBlue = (double *) malloc(colormapSize * sizeof(double));
    MCHECK(dRed); MCHECK(dGreen); MCHECK(dBlue);

    /*
     * If TIFFTAG_PHOTOMETRIC is not present then assign a reasonable default.
     * The TIFF 5.0 specification doesn't give a default.
     */
    if (!TIFFGetField(tfFile, TIFFTAG_PHOTOMETRIC,
            &tfPhotometricInterpretation)) {
        if (tfSamplesPerPixel != 1)
            tfPhotometricInterpretation = PHOTOMETRIC_RGB;
        else if (tfBitsPerSample == 1)
            tfPhotometricInterpretation = PHOTOMETRIC_MINISBLACK;
        else if (TIFFGetField(tfFile, TIFFTAG_COLORMAP,
                &redMap, &greenMap, &blueMap)) {
            tfPhotometricInterpretation = PHOTOMETRIC_PALETTE;
            redMap = greenMap = blueMap = NULL;
        } else
            tfPhotometricInterpretation = PHOTOMETRIC_MINISBLACK;
    }

    /*
     * Given TIFFTAG_PHOTOMETRIC extract or create the response curves.
     */
    switch (tfPhotometricInterpretation) {
    case PHOTOMETRIC_RGB:
	redMap = (u_short *) malloc(colormapSize * sizeof(u_short));
	greenMap = (u_short *) malloc(colormapSize * sizeof(u_short));
	blueMap = (u_short *) malloc(colormapSize * sizeof(u_short));
	MCHECK(redMap); MCHECK(greenMap); MCHECK(blueMap);
	for (i = 0; i < colormapSize; i++)
	    dRed[i] = dGreen[i] = dBlue[i]
		= (double) SCALE(i, colormapSize - 1);
        break;
    case PHOTOMETRIC_PALETTE:
        if (!TIFFGetField(tfFile, TIFFTAG_COLORMAP,
                &redMap, &greenMap, &blueMap)) {
            redMap = (u_short *) malloc(colormapSize * sizeof(u_short));
            greenMap = (u_short *) malloc(colormapSize * sizeof(u_short));
            blueMap = (u_short *) malloc(colormapSize * sizeof(u_short));
            MCHECK(redMap); MCHECK(greenMap); MCHECK(blueMap);
            for (i = 0; i < colormapSize; i++)
                dRed[i] = dGreen[i] = dBlue[i]
                    = (double) SCALE(i, colormapSize - 1);
        } else {
            CheckAndCorrectColormap();
            for (i = 0; i < colormapSize; i++) {
                dRed[i] = (double) redMap[i];
                dGreen[i] = (double) greenMap[i];
                dBlue[i] = (double) blueMap[i];
            }
        }
        break;
    case PHOTOMETRIC_MINISWHITE:
        redMap = (u_short *) malloc(colormapSize * sizeof(u_short));
        greenMap = (u_short *) malloc(colormapSize * sizeof(u_short));
        blueMap = (u_short *) malloc(colormapSize * sizeof(u_short));
        MCHECK(redMap); MCHECK(greenMap); MCHECK(blueMap);
	for (i = 0; i < colormapSize; i++)
	    dRed[i] = dGreen[i] = dBlue[i] = (double)
		 SCALE(colormapSize-1-i, colormapSize-1);
        break;
    case PHOTOMETRIC_MINISBLACK:
        redMap = (u_short *) malloc(colormapSize * sizeof(u_short));
        greenMap = (u_short *) malloc(colormapSize * sizeof(u_short));
        blueMap = (u_short *) malloc(colormapSize * sizeof(u_short));
        MCHECK(redMap); MCHECK(greenMap); MCHECK(blueMap);
	for (i = 0; i < colormapSize; i++)
	    dRed[i] = dGreen[i] = dBlue[i] = (double) SCALE(i, colormapSize-1);
        break;
    default:
        fprintf(stderr,
            "xtiff: can't display photometric interpretation type %d\n",
            tfPhotometricInterpretation);
        exit(0);
    }
}

void
SetNameLabel()
{
    char buffer[BUFSIZ];
    Arg args[1];

    if (tfMultiPage)
        sprintf(buffer, "%s - page %d", fileName, tfDirectory);
    else
        strcpy(buffer, fileName);
    XtSetArg(args[0], XtNlabel, buffer);
    XtSetValues(labelWidget, args, 1);
}

/*
 * Many programs get TIFF colormaps wrong.  They use 8-bit colormaps instead of
 * 16-bit colormaps.  This function is a heuristic to detect and correct this.
 */
void
CheckAndCorrectColormap()
{
    register int i;

    for (i = 0; i < colormapSize; i++)
        if ((redMap[i] > 255) || (greenMap[i] > 255) || (blueMap[i] > 255))
            return;

    for (i = 0; i < colormapSize; i++) {
        redMap[i] = SCALE(redMap[i], 255);
        greenMap[i] = SCALE(greenMap[i], 255);
        blueMap[i] = SCALE(blueMap[i], 255);
    }
    TIFFWarning(fileName, "Assuming 8-bit colormap");
}

void
SimpleGammaCorrection()
{
    register int i;
    register double i_gamma = 1.0 / appData.gamma;

    for (i = 0; i < colormapSize; i++) {
        if (((tfPhotometricInterpretation == PHOTOMETRIC_MINISWHITE)
            && (i == colormapSize - 1))
            || ((tfPhotometricInterpretation == PHOTOMETRIC_MINISBLACK)
            && (i == 0)))
            redMap[i] = greenMap[i] = blueMap[i] = 0;
        else {
            redMap[i] = ROUND((pow(dRed[i] / 65535.0, i_gamma) * 65535.0));
            greenMap[i] = ROUND((pow(dGreen[i] / 65535.0, i_gamma) * 65535.0));
            blueMap[i] = ROUND((pow(dBlue[i] / 65535.0, i_gamma) * 65535.0));
        }
    }

    free(dRed); free(dGreen); free(dBlue);
}

static char* classNames[] = {
    "StaticGray",
    "GrayScale",
    "StaticColor",
    "PseudoColor",
    "TrueColor",
    "DirectColor"
};

/*
 * Current limitation: the visual is set initially by the first file.
 * It cannot be changed.
 */
void
GetVisual()
{
    register XColor *colors = NULL;
    register u_long *pixels = NULL;
    register int i;

    switch (tfImageDepth) {
    /*
     * X really wants a 32-bit image with the fourth channel unused,
     * but the visual structure thinks it's 24-bit.  bitmap_unit is 32.
     */
    case 32:
    case 24:
        if (SearchVisualList(24, DirectColor, &xVisual) == False) {
            fprintf(stderr, "xtiff: 24-bit DirectColor visual not available\n");
            exit(0);
        }

        colors = (XColor *) malloc(3 * colormapSize * sizeof(XColor));
        MCHECK(colors);

        for (i = 0; i < colormapSize; i++) {
            colors[i].pixel = (u_long) (i << 16) + (i << 8) + i;
            colors[i].red = redMap[i];
            colors[i].green = greenMap[i];
            colors[i].blue = blueMap[i];
            colors[i].flags = DoRed | DoGreen | DoBlue;
        }

        xColormap = XCreateColormap(xDisplay, RootWindow(xDisplay, xScreen),
            xVisual, AllocAll);
        XStoreColors(xDisplay, xColormap, colors, colormapSize);
        break;
    case 8:
    case 4:
    case 2:
        /*
         * We assume that systems with 24-bit visuals also have 8-bit visuals.
         * We don't promote from 8-bit PseudoColor to 24/32 bit DirectColor.
         */
        switch (tfPhotometricInterpretation) {
        case PHOTOMETRIC_MINISWHITE:
        case PHOTOMETRIC_MINISBLACK:
            if (SearchVisualList((int) tfImageDepth, GrayScale, &xVisual) == True)
                break;
        case PHOTOMETRIC_PALETTE:
            if (SearchVisualList((int) tfImageDepth, PseudoColor, &xVisual) == True)
                break;
        default:
            fprintf(stderr, "xtiff: Unsupported TIFF/X configuration\n");
            exit(0);
        }

        colors = (XColor *) malloc(colormapSize * sizeof(XColor));
        MCHECK(colors);

        for (i = 0; i < colormapSize; i++) {
            colors[i].pixel = (u_long) i;
            colors[i].red = redMap[i];
            colors[i].green = greenMap[i];
            colors[i].blue = blueMap[i];
            colors[i].flags = DoRed | DoGreen | DoBlue;
        }

        /*
         * xtiff's colormap allocation is private.  It does not attempt
         * to detect whether any existing colormap entries are suitable
         * for its use.  This will cause colormap flashing.  Furthermore,
         * background and foreground are taken from the environment.
         * For example, the foreground color may be red when the visual
         * is GrayScale.  If the colormap is completely populated,
         * Xt will not be able to allocate fg and bg.
         */
        if (tfImageDepth == 8)
            xColormap = XCreateColormap(xDisplay, RootWindow(xDisplay, xScreen),
                xVisual, AllocAll);
        else {
            xColormap = XCreateColormap(xDisplay, RootWindow(xDisplay, xScreen),
                xVisual, AllocNone);
            pixels = (u_long *) malloc(colormapSize * sizeof(u_long));
            MCHECK(pixels);
            (void) XAllocColorCells(xDisplay, xColormap, True,
                NULL, 0, pixels, colormapSize);
            basePixel = (u_char) pixels[0];
            free(pixels);
        }
        XStoreColors(xDisplay, xColormap, colors, colormapSize);
        break;
    case 1:
        xImageDepth = 1;
        xVisual = DefaultVisual(xDisplay, xScreen);
        xColormap = DefaultColormap(xDisplay, xScreen);
        break;
    default:
        fprintf(stderr, "xtiff: unsupported image depth %d\n", tfImageDepth);
        exit(0);
    }

    if (appData.verbose == True)
	fprintf(stderr, "%s: Using %d-bit %s visual.\n",
	    fileName, xImageDepth, classNames[xVisual->class]);

    if (colors != NULL)
        free(colors);
    if (grayMap != NULL)
        free(grayMap);
    if (redMap != NULL)
        free(redMap);
    if (greenMap != NULL)
        free(greenMap);
    if (blueMap != NULL)
        free(blueMap);

    colors = NULL; grayMap = redMap = greenMap = blueMap = NULL;
}

/*
 * Search for an appropriate visual.  Promote where necessary.
 * Check to make sure that ENOUGH colormap entries are writeable.
 * basePixel was determined when XAllocColorCells() contiguously
 * allocated enough entries.  basePixel is used below in GetTIFFImage.
 */
Boolean
SearchVisualList(image_depth, visual_class, visual)
    int image_depth, visual_class;
    Visual **visual;
{
    XVisualInfo template_visual, *visual_list, *vl;
    int i, n_visuals;

    template_visual.screen = xScreen;
    vl = visual_list = XGetVisualInfo(xDisplay, VisualScreenMask,
        &template_visual, &n_visuals);

    if (n_visuals == 0) {
        fprintf(stderr, "xtiff: visual list not available\n");
        exit(0);
    }

    for (i = 0; i < n_visuals; vl++, i++) {
        if ((vl->class == visual_class) && (vl->depth >= image_depth)
            && (vl->visual->map_entries >= (1 << vl->depth))) {
            *visual = vl->visual;
            xImageDepth = vl->depth;
            xRedMask = vl->red_mask;
            xGreenMask = vl->green_mask;
            xBlueMask = vl->blue_mask;
            XFree((char *) visual_list);
            return True;
        }
    }

    XFree((char *) visual_list);
    return False;
}

void
GetTIFFImage()
{
    int pixel_map[3], red_shift, green_shift, blue_shift;
    register u_char *scan_line, *output_p, *input_p;
    register int i, j, s;

    scan_line = (u_char *) malloc(tfBytesPerRow = TIFFScanlineSize(tfFile));
    MCHECK(scan_line);

    if ((tfImageDepth == 32) || (tfImageDepth == 24)) {
        output_p = imageMemory = (u_char *)
            malloc(tfImageWidth * tfImageHeight * 4);
        MCHECK(imageMemory);

        /*
         * Handle different color masks for different frame buffers.
         */
        if (ImageByteOrder(xDisplay) == LSBFirst) { /* DECstation 5000 */
            red_shift = pixel_map[0] = xRedMask == 0xFF000000 ? 3
                : (xRedMask == 0xFF0000 ? 2 : (xRedMask == 0xFF00 ? 1 : 0));
            green_shift = pixel_map[1] = xGreenMask == 0xFF000000 ? 3
                : (xGreenMask == 0xFF0000 ? 2 : (xGreenMask == 0xFF00 ? 1 : 0));
            blue_shift = pixel_map[2] = xBlueMask == 0xFF000000 ? 3
                : (xBlueMask == 0xFF0000 ? 2 : (xBlueMask == 0xFF00 ? 1 : 0));
        } else { /* Ardent */
            red_shift = pixel_map[0] = xRedMask == 0xFF000000 ? 0
                : (xRedMask == 0xFF0000 ? 1 : (xRedMask == 0xFF00 ? 2 : 3));
            green_shift = pixel_map[0] = xGreenMask == 0xFF000000 ? 0
                : (xGreenMask == 0xFF0000 ? 1 : (xGreenMask == 0xFF00 ? 2 : 3));
            blue_shift = pixel_map[0] = xBlueMask == 0xFF000000 ? 0
                : (xBlueMask == 0xFF0000 ? 1 : (xBlueMask == 0xFF00 ? 2 : 3));
        }

        if (tfPlanarConfiguration == PLANARCONFIG_CONTIG) {
            for (i = 0; i < tfImageHeight; i++) {
                if (TIFFReadScanline(tfFile, scan_line, i, 0) < 0)
                    break;
                for (input_p = scan_line, j = 0; j < tfImageWidth; j++) {
                    *(output_p + red_shift) = *input_p++;
                    *(output_p + green_shift) = *input_p++;
                    *(output_p + blue_shift) = *input_p++;
                    output_p += 4;
                    if (tfSamplesPerPixel == 4) /* skip the fourth channel */
                        input_p++;
                }
            }
        } else {
            for (s = 0; s < tfSamplesPerPixel; s++) {
                if (s == 3)             /* skip the fourth channel */
                    continue;
                for (i = 0; i < tfImageHeight; i++) {
                    if (TIFFReadScanline(tfFile, scan_line, i, s) < 0)
                        break;
                    input_p = scan_line;
                    output_p = imageMemory + (i*tfImageWidth*4) + pixel_map[s];
                    for (j = 0; j < tfImageWidth; j++, output_p += 4)
                        *output_p = *input_p++;
                }
            }
        }
    } else {
        if (xImageDepth == tfImageDepth) {
            output_p = imageMemory = (u_char *)
                malloc(tfBytesPerRow * tfImageHeight);
            MCHECK(imageMemory);

            for (i = 0; i < tfImageHeight; i++, output_p += tfBytesPerRow)
                if (TIFFReadScanline(tfFile, output_p, i, 0) < 0)
                    break;
        } else if ((xImageDepth == 8) && (tfImageDepth == 4)) {
            output_p = imageMemory = (u_char *)
                malloc(tfBytesPerRow * 2 * tfImageHeight + 2);
            MCHECK(imageMemory);

            /*
             * If a scanline is of odd size the inner loop below will overshoot.
             * This is handled very simply by recalculating the start point at
             * each scanline and padding imageMemory a little at the end.
             */
            for (i = 0; i < tfImageHeight; i++) {
                if (TIFFReadScanline(tfFile, scan_line, i, 0) < 0)
                    break;
                output_p = &imageMemory[i * tfImageWidth];
                input_p = scan_line;
                for (j = 0; j < tfImageWidth; j += 2, input_p++) {
                    *output_p++ = (*input_p >> 4) + basePixel;
                    *output_p++ = (*input_p & 0xf) + basePixel;
                }
            }
        } else if ((xImageDepth == 8) && (tfImageDepth == 2)) {
            output_p = imageMemory = (u_char *)
                malloc(tfBytesPerRow * 4 * tfImageHeight + 4);
            MCHECK(imageMemory);

            for (i = 0; i < tfImageHeight; i++) {
                if (TIFFReadScanline(tfFile, scan_line, i, 0) < 0)
                    break;
                output_p = &imageMemory[i * tfImageWidth];
                input_p = scan_line;
                for (j = 0; j < tfImageWidth; j += 4, input_p++) {
                    *output_p++ = (*input_p >> 6) + basePixel;
                    *output_p++ = ((*input_p >> 4) & 3) + basePixel;
                    *output_p++ = ((*input_p >> 2) & 3) + basePixel;
                    *output_p++ = (*input_p & 3) + basePixel;
                }
            }
        } else if ((xImageDepth == 4) && (tfImageDepth == 2)) {
            output_p = imageMemory = (u_char *)
                malloc(tfBytesPerRow * 2 * tfImageHeight + 2);
            MCHECK(imageMemory);

            for (i = 0; i < tfImageHeight; i++) {
                if (TIFFReadScanline(tfFile, scan_line, i, 0) < 0)
                    break;
                output_p = &imageMemory[i * tfBytesPerRow * 2];
                input_p = scan_line;
                for (j = 0; j < tfImageWidth; j += 4, input_p++) {
                    *output_p++ = (((*input_p>>6) << 4)
                        | ((*input_p >> 4) & 3)) + basePixel;
                    *output_p++ = ((((*input_p>>2) & 3) << 4)