gif2epsn.c

来自「在EM85XX」· C语言 代码 · 共 594 行 · 第 1/2 页

    };
    static char Dither3[3][3] = {
	{ 7, 9, 5 },
	{ 2, 1, 4 },
	{ 6, 3, 8 }
    };
    static char Dither4[4][4] = {
	{ 1,  9,  3,  11 },
	{ 13, 5,  15, 7 },
	{ 4,  12, 2,  10 },
	{ 16, 8,  14, 6 }
    };
    int i, j, k, Level;
    long Intensity;
    GifColorType *ColorMapEntry;

    /* Scan the Rows (Size rows) evaluate intensity every Size pixel and use */
    /* the dither matrix to set the dithered result;			     */
    for (i = 0; i <= RowSize - DitherSize; i += DitherSize) {
	Intensity = 0;
	for (j = Row; j < Row + DitherSize; j++)
	    for (k = 0; k < DitherSize; k++) {
		ColorMapEntry = &ColorMap[ScreenBuffer[j][i+k]];
		Intensity += 30 * ((int) ColorMapEntry->Red) +
			     59 * ((int) ColorMapEntry->Green) +
			     11 * ((int) ColorMapEntry->Blue);
	    }

	/* Find the intensity level (between 0 and Size^2) of our matrix:    */
	/* Expression is "Intensity * BWThreshold / (25500 * DefThresh)"     */
	/* but to prevent from overflow in the long evaluation we do this:   */
	Level = ((Intensity / 2550) * ((long) DEFAULT_THRESHOLD) /
						(((long) BWThreshold) * 10));
	switch (DitherSize) {
	    case 2:     
		for (j = 0; j < DitherSize; j++)
		    for (k = 0; k < DitherSize; k++)
			DitherBuffer[j][i+k] = Dither2[j][k] <= Level;
		break;
	    case 3:
		for (j = 0; j < DitherSize; j++)
		    for (k = 0; k < DitherSize; k++)
			DitherBuffer[j][i+k] = Dither3[j][k] <= Level;
		break;
	    case 4:
		for (j = 0; j < DitherSize; j++)
		    for (k = 0; k < DitherSize; k++)
			DitherBuffer[j][i+k] = Dither4[j][k] <= Level;
		break;
	}
    }
}

/******************************************************************************
* The real dumping routine. Few things are taken into account:		      *
* 1. The Nice flag. If TRUE each pixel is printed twice in double density.    *
* 2. The Invert flag. If TRUE each pixel before drawn is inverted.	      *
* 3. The rendering mode and dither matrix flag if dithering is selected.      *
*   The image is drawn from ScreenBuffer ScreenTop/Left in the bottom/right   *
* directions.							     	      *
*   Unfortunatelly, there is a BUG in DOS that does not handle ctrl-Z	      *
* correctly if we open lptx: device in binary mode (should treat it as any    *
* other char). Therefore I had to write to it directly using biosprint. I     *
* dont like it either, and if you have better way to do it, let me know.      *
******************************************************************************/
static void DumpScreen2Epsn(GifRowType *ScreenBuffer,
					int ScreenWidth, int ScreenHeight)
{
    int i, j, p, Size, LeftCWidth, Len, DirectPrint = 0,
	DitheredLinesLeft = 0, DitheredLinesCount = 0, MapInvert[2];
    char LinePrefixLen[2];			     /* Length of scan line. */
    GifByteType *EpsonBuffer;
    GifPixelType *Line;
    GifRowType *DitherBuffer;
    GifColorType *ColorMapEntry;
    FILE *Prt = NULL;

#ifdef __MSDOS__
    for (i = 0;	 i < strlen(PrinterName); i++)
	if (islower(PrinterName[i]))
	    PrinterName[i] = toupper(PrinterName[i]);

    if (strcmp(PrinterName, "LPT1") == 0 ||
	strcmp(PrinterName, "PRN") == 0)
	DirectPrint = 1;
    else if (strcmp(PrinterName, "LPT2") == 0)
        DirectPrint = 2;
    else if (strcmp(PrinterName, "LPT3") == 0)
        DirectPrint = 3;
#endif /* __MSDOS__ */

    if (!DirectPrint) {
#ifdef __MSDOS__
	if (strlen(PrinterName) == 0) {
	    setmode(1, O_BINARY);	  /* Make sure it is in binary mode. */
	    Prt = stdout;
	}
	else if ((Prt = fopen(PrinterName, "wb")) == NULL ||
		 setvbuf(Prt, NULL, _IOFBF, GIF_FILE_BUFFER_SIZE))
#else
	if (strlen(PrinterName) == 0)
	    Prt = stdout;
	else if ((Prt = fopen(PrinterName, "w")) == NULL)
#endif /* __MSDOS__ */
	    GIF_EXIT("Failed to open output (printer) file.");
    }

    if ((EpsonBuffer = (GifByteType *) malloc(ScreenWidth)) == NULL)
	GIF_EXIT("Failed to allocate memory required, aborted.");

    /* Allocate the buffer to save the dithered information. */
    if (ColorToBWMapping == C2BW_DITHER) {
	if ((DitherBuffer = (GifRowType *)
	    malloc(DITHER_MAX_MATRIX * sizeof(GifRowType *))) != NULL) {
	    Size = ScreenWidth * sizeof(GifPixelType);	 /* Size of one row. */
	    for (i = 0; i < DITHER_MAX_MATRIX; i++) {
		if ((DitherBuffer[i] = (GifRowType) malloc(Size)) == NULL) {
		    DitherBuffer = NULL;
		    break;
		}
	    }
	}
	if (DitherBuffer == NULL)
	    GIF_EXIT("Failed to allocate memory required, aborted.");
    }
    else
	DitherBuffer = NULL;

    /* Reset the printer, and make sure no space between adjacent lines: */
    PutString(Prt, DirectPrint, EPSON_RESET, 2);
    PutString(Prt, DirectPrint, EPSON_VERTICAL_SPACE, 3);

    /* Prepar left spacing to begin with, so image will be in the middle.    */
    LeftCWidth = (EPSON_WIDTH - (ScreenWidth / EPSON_PIXEL_2_CHAR)) / 2;

    if (InvertFlag) {		   /* Make the inversion as fast a possible. */
	MapInvert[0] = 1;
	MapInvert[1] = 0;
    }
    else {
	MapInvert[0] = 0;
	MapInvert[1] = 1;
    }

    for (i = 0, p = 0; i < ScreenHeight; i++, p++) {
	GifQprintf("\b\b\b\b%-4d", ScreenHeight - i);
	Line = ScreenBuffer[i];

	/* If 8 lines were accumulated in printer buffer - dump them out.    */
	if (p == 8) {
	    for (Len = ScreenWidth-1; Len >= 0; Len--)
	        if (EpsonBuffer[Len]) break;

	    /* Only in case this line is not empty: */
	    if (Len++ >= 0) {
		/* Make the left space, so image will be centered: */
		for (j = 0; j < LeftCWidth; j++)
		    PutString(Prt, DirectPrint,  " ", 1);

		/* Full printer line is ready to be dumped - send it out: */
		if (NiceFlag) {
		    PutString(Prt, DirectPrint, EPSON_DUAL_DENSITY, 2);
		    LinePrefixLen[0] = (Len * 2) % 256;
		    LinePrefixLen[1] = (Len * 2) / 256;
		    PutString(Prt, DirectPrint, LinePrefixLen, 2);
		    PutString2(Prt, DirectPrint, (char *) EpsonBuffer, Len);
		}
		else {
		    PutString(Prt, DirectPrint, EPSON_REG_DENSITY, 2);
		    LinePrefixLen[0] = Len % 256;
		    LinePrefixLen[1] = Len / 256;
		    PutString(Prt, DirectPrint, LinePrefixLen, 2);
		    PutString(Prt, DirectPrint, (char *) EpsonBuffer, Len);
		}
	    }
	    PutString(Prt, DirectPrint, "\015\012", 2);
	    p = 0;
	}

	/* We decide right here what method to map Colors to BW so the inner */
	/* loop will be independent of it (and therefore faster):	     */
	switch(ColorToBWMapping) {
	    case C2BW_BACK_GROUND:
		for (j = 0; j < ScreenWidth; j++)
		    EpsonBuffer[j] = (EpsonBuffer[j] << 1) +
					MapInvert[Line[j] != BackGround];
		break;
	    case C2BW_GREY_LEVELS:
		for (j = 0; j < ScreenWidth; j++) {
		    ColorMapEntry = &ColorMap[Line[j]];
		    /* For the transformation from RGB to BW, see Folley &   */
		    /* Van Dam pp 613: The Y channel is the BW we need:	     */
		    /* As colors are 255 maximum, the result can be up to    */
		    /* 25500 which is still in range of our 16 bits integers */
		    EpsonBuffer[j] = (EpsonBuffer[j] << 1) +
			MapInvert[(30 * (int) ColorMapEntry->Red) +
				   59 * ((int) ColorMapEntry->Green) +
				   11 * ((int) ColorMapEntry->Blue) >
					BWThreshold];
		}
		break;
	    case C2BW_DITHER:
		if (DitheredLinesLeft-- == 0) {
		    EvalDitheredScanline(ScreenBuffer,
			(i < ScreenHeight - DitherSize ? i :
						 ScreenHeight - DitherSize),
			ScreenWidth, DitherBuffer);
		    DitheredLinesLeft = DitherSize - 1;
		    DitheredLinesCount = 0;
		}
		Line = DitherBuffer[DitheredLinesCount++];
		for (j = 0; j < ScreenWidth; j++)
		    EpsonBuffer[j] = (EpsonBuffer[j] << 1) +
							MapInvert[Line[j]];
		break;
	}
    }

    /* If buffer in incomplete - complete it and dump it out: */
    if (p != 0) {
	for (Len = ScreenWidth - 1; Len >= 0; Len--)
	    if (EpsonBuffer[Len]) break;
	if (Len++ >= 0) {
	    i = 8 - p;					 /* Amount to shift. */
	    for (j = 0; j < ScreenWidth; j++) EpsonBuffer[j] <<= i;

	    /* Make the left space, so image will be centered: */
	    for (j = 0; j < LeftCWidth; j++)
		PutString(Prt, DirectPrint, " ", 1);

	    if (NiceFlag) {
		PutString(Prt, DirectPrint, EPSON_DUAL_DENSITY, 2);
		LinePrefixLen[0] = (Len * 2) % 256;
		LinePrefixLen[1] = (Len * 2) / 256;
		PutString(Prt, DirectPrint, LinePrefixLen, 2);
		PutString2(Prt, DirectPrint, (char *) EpsonBuffer, Len);
	    }
	    else {
		PutString(Prt, DirectPrint, EPSON_REG_DENSITY, 2);
		LinePrefixLen[0] = Len % 256;
		LinePrefixLen[1] = Len / 256;
		PutString(Prt, DirectPrint, LinePrefixLen, 2);
		PutString(Prt, DirectPrint, (char *) EpsonBuffer, Len);
	    }
	}
	PutString(Prt, DirectPrint, "\015\012", 2);
    }

    fclose(Prt);
}

/******************************************************************************
* Dumps the string of given length, to Prt. No char in Str has special	      *
* meaning, and even zero (NULL) chars are dumped.			      *
* If however DirectPrint is non zero, string is dumped to specifed lpt port.  *
******************************************************************************/
static void PutString(FILE *Prt, int DirectPrint, char *Str, int Len)
{
    int i;

    if (DirectPrint) {
#ifdef __MSDOS__
	for (i = 0; i < Len; i++) biosprint(0, Str[i], DirectPrint - 1);
#else
	GIF_EXIT("Can not print directly to a printer if not MSDOS.");
#endif /* __MSDOS__ */
    }
    else
	for (i = 0; i < Len; i++) fputc(Str[i], Prt);
}

/******************************************************************************
* Dumps the string of given length, to Prt. No char in Str has special	      *
* meaning, and even zero (NULL) chars are dumped. Every char is dumped twice. *
* If however DirectPrint is non zero, string is dumped to specifed lpt port.  *
******************************************************************************/
static void PutString2(FILE *Prt, int DirectPrint, char *Str, int Len)
{
    int i;

    if (DirectPrint) {
#ifdef __MSDOS__
	for (i = 0; i < Len; i++) {
	    biosprint(0, Str[i], DirectPrint - 1);
	    biosprint(0, Str[i], DirectPrint - 1);
	}
#else
	GIF_EXIT("Can not print directly to a printer if not MSDOS.");
#endif /* __MSDOS__ */
    }
    else
	for (i = 0; i < Len; i++) {
	    fputc(Str[i], Prt);
	    fputc(Str[i], Prt);
	}
}