ghostscript-7.07/src/gximage1.c

/* Copyright (C) 1989, 2000 artofcode LLC.  All rights reserved.

  This program is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by the
  Free Software Foundation; either version 2 of the License, or (at your
  option) any later version.

  This program is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License along
  with this program; if not, write to the Free Software Foundation, Inc.,
  59 Temple Place, Suite 330, Boston, MA, 02111-1307.

*/

/*$Id: gximage1.c,v 1.5.6.1.2.1 2003/01/17 00:49:04 giles Exp $ */
/* ImageType 1 initialization */
#include "gx.h"
#include "gserrors.h"
#include "gxiparam.h"
#include "gximage.h"
#include "stream.h"

/* Structure descriptor */
public_st_gs_image1();

/*
 * Define the image types for ImageType 1 images.
 * Note that opaque images and masks have different types, although
 * they have the same ImageType.
 */
private image_proc_sput(gx_image1_sput);
private image_proc_sget(gx_image1_sget);
private image_proc_release(gx_image1_release);
const gx_image_type_t gs_image_type_1 = {
    &st_gs_image1, gx_begin_image1, gx_data_image_source_size,
    gx_image1_sput, gx_image1_sget, gx_image1_release, 1
};
private image_proc_sput(gx_image1_mask_sput);
private image_proc_sget(gx_image1_mask_sget);
/*
 * Image masks are not actually pixel images, so they don't need to
 * worry about releasing the color space.
 */
const gx_image_type_t gs_image_type_mask1 = {
    &st_gs_image1, gx_begin_image1, gx_data_image_source_size,
    gx_image1_mask_sput, gx_image1_mask_sget, gx_image_default_release, 1
};

/* Define the procedures for initializing gs_image_ts to default values. */
void
gs_image_t_init_adjust(gs_image_t * pim, const gs_color_space * color_space,
		       bool adjust)
{
    gs_pixel_image_t_init((gs_pixel_image_t *) pim, color_space);
    pim->ImageMask = (color_space == NULL);
    pim->adjust = adjust;
    pim->type = (pim->ImageMask ? &gs_image_type_mask1 : &gs_image_type_1);
    pim->Alpha = gs_image_alpha_none;
}
void
gs_image_t_init_mask_adjust(gs_image_t * pim, bool write_1s, bool adjust)
{
    gs_image_t_init(pim, NULL);
    if (write_1s)
	pim->Decode[0] = 1, pim->Decode[1] = 0;
    else
	pim->Decode[0] = 0, pim->Decode[1] = 1;
    pim->adjust = adjust;
}

/* Start processing an ImageType 1 image. */
int
gx_begin_image1(gx_device * dev,
		const gs_imager_state * pis, const gs_matrix * pmat,
		const gs_image_common_t * pic, const gs_int_rect * prect,
		const gx_drawing_color * pdcolor, const gx_clip_path * pcpath,
		gs_memory_t * mem, gx_image_enum_common_t ** pinfo)
{
    gx_image_enum *penum;
    const gs_image_t *pim = (const gs_image_t *)pic;
    int code = gx_image_enum_alloc(pic, prect, mem, &penum);

    if (code < 0)
	return code;
    penum->alpha = pim->Alpha;
    penum->use_mask_color = false;
    penum->masked = pim->ImageMask;
    penum->adjust =
	(pim->ImageMask && pim->adjust ? float2fixed(0.25) : fixed_0);
    code = gx_image_enum_begin(dev, pis, pmat, pic, pdcolor, pcpath, mem,
			       penum);
    if (code >= 0)
	*pinfo = (gx_image_enum_common_t *)penum;
    return code;
}

/* Serialization */

/*
 * We add the Alpha value to the control word.
 */

private int
gx_image1_sput(const gs_image_common_t *pic, stream *s,
	       const gs_color_space **ppcs)
{
    const gs_image_t *const pim = (const gs_image_t *)pic;

    return gx_pixel_image_sput((const gs_pixel_image_t *)pic, s, ppcs,
			       (int)pim->Alpha);
}

private int
gx_image1_sget(gs_image_common_t *pic, stream *s,
	       const gs_color_space *pcs)
{
    gs_image1_t *const pim = (gs_image1_t *)pic;
    int code = gx_pixel_image_sget((gs_pixel_image_t *)pim, s, pcs);

    if (code < 0)
	return code;
    pim->type = &gs_image_type_1;
    pim->ImageMask = false;
    pim->Alpha = code;
    return 0;
}

/*
 * Masks have different parameters, so we use a different encoding:
 *	FFFFEEDCBA
 *	    A = 0 if standard ImageMatrix, 1 if explicit ImageMatrix
 *	    B = 0 if Decode=[0 1], 1 if Decode=[1 0]
 *	    C = Interpolate
 *	    D = adjust
 *	    EE = Alpha
 *	    FFFF = BitsPerComponent - 1 (only needed for soft masks)
 *	Width, encoded as a variable-length uint
 *	Height, encoded like Width
 *	ImageMatrix (if A = 1), per gs_matrix_store/fetch
 */
#define MI_ImageMatrix 0x01
#define MI_Decode 0x02
#define MI_Interpolate 0x04
#define MI_adjust 0x08
#define MI_Alpha_SHIFT 4
#define MI_Alpha_MASK 0x3
#define MI_BPC_SHIFT 6
#define MI_BPC_MASK 0xf
#define MI_BITS 10

private int
gx_image1_mask_sput(const gs_image_common_t *pic, stream *s,
		    const gs_color_space **ignore_ppcs)
{
    const gs_image_t *pim = (const gs_image_t *)pic;
    uint control =
	(gx_image_matrix_is_default((const gs_data_image_t *)pim) ? 0 :
	 MI_ImageMatrix) |
	(pim->Decode[0] != 0 ? MI_Decode : 0) |
	(pim->Interpolate ? MI_Interpolate : 0) |
	(pim->adjust ? MI_adjust : 0) |
	(pim->Alpha << MI_Alpha_SHIFT) |
	((pim->BitsPerComponent - 1) << MI_BPC_SHIFT);

    sput_variable_uint(s, control);
    sput_variable_uint(s, (uint)pim->Width);
    sput_variable_uint(s, (uint)pim->Height);
    if (control & MI_ImageMatrix)
	sput_matrix(s, &pim->ImageMatrix);
    return 0;
}

private int
gx_image1_mask_sget(gs_image_common_t *pic, stream *s,
		    const gs_color_space *ignore_pcs)
{
    gs_image1_t *const pim = (gs_image1_t *)pic;
    int code;
    uint control;

    if ((code = sget_variable_uint(s, &control)) < 0)
	return code;
    gs_image_t_init_mask(pim, (control & MI_Decode) != 0);
    if ((code = sget_variable_uint(s, (uint *)&pim->Width)) < 0 ||
	(code = sget_variable_uint(s, (uint *)&pim->Height)) < 0
	)
	return code;
    if (control & MI_ImageMatrix) {
	if ((code = sget_matrix(s, &pim->ImageMatrix)) < 0)
	    return code;
    } else
	gx_image_matrix_set_default((gs_data_image_t *)pim);
    pim->Interpolate = (control & MI_Interpolate) != 0;
    pim->adjust = (control & MI_adjust) != 0;
    pim->Alpha = (control >> MI_Alpha_SHIFT) & MI_Alpha_MASK;
    pim->BitsPerComponent = ((control >> MI_BPC_SHIFT) & MI_BPC_MASK) + 1;
    return 0;
}

private void
gx_image1_release(gs_image_common_t *pic, gs_memory_t *mem)
{
    gx_pixel_image_release((gs_pixel_image_t *)pic, mem);
}