path: root/devices/gdevpbm.c

/* Copyright (C) 2001-2023 Artifex Software, Inc.
   All Rights Reserved.

   This software is provided AS-IS with no warranty, either express or
   implied.

   This software is distributed under license and may not be copied,
   modified or distributed except as expressly authorized under the terms
   of the license contained in the file LICENSE in this distribution.

   Refer to licensing information at http://www.artifex.com or contact
   Artifex Software, Inc.,  39 Mesa Street, Suite 108A, San Francisco,
   CA 94129, USA, for further information.
*/

/* Portable Bit/Gray/PixMap drivers */
#include "gdevprn.h"
#include "gscdefs.h"
#include "gscspace.h" /* For pnm_begin_typed_image(..) */
#include "gxgetbit.h"
#include "gxlum.h"
#include "gxiparam.h" /* For pnm_begin_typed_image(..) */
#include "gdevmpla.h"
#include "gdevplnx.h"
#include "gdevppla.h"

/*
 * Thanks are due to Jos Vos (jos@bull.nl) for an earlier P*M driver,
 * on which this one is based; to Nigel Roles (ngr@cotswold.demon.co.uk),
 * for the plan9bm changes; and to Leon Bottou (leonb@research.att.com)
 * for the color detection code in pnm_begin_typed_image.
 */

/*
 * There are 8 (families of) drivers here, plus one less related one:
 *      pbm[raw] - outputs PBM (black and white).
 *      pgm[raw] - outputs PGM (gray-scale).
 *      pgnm[raw] - outputs PBM if the page contains only black and white,
 *        otherwise PGM.
 *      ppm[raw] - outputs PPM (RGB).
 *      pnm[raw] - outputs PBM if the page contains only black and white,
 *        otherwise PGM if the page contains only gray shades,
 *        otherwise PPM.
 *        If GrayDetection is true, then the pageneutral color is used to decide
          between PGM and PPM.
 *      pkm[raw] - computes internally in CMYK, outputs PPM (RGB).
 *      pksm[raw] - computes internally in CMYK, outputs 4 PBM pages.
 *      pamcmyk4 - outputs CMYK as PAM 1-bit per color
 *      pamcmyk32 - outputs CMYK as PAM 8-bits per color
 *      pnmcmyk - With GrayDetection true, outputs either the 8-bit K plane as PGM or
 *                32-bit CMYK (pam 8-bit per component) depending on pageneutralcolor.
 *      pam - previous name for the pamcmyk32 device retained for backwards compatibility
 *      plan9bm - outputs Plan 9 bitmap format.
 */

/*
 * The code here is designed to work with variable depths for PGM and PPM.
 * The code will work with any of the values in brackets, but the
 * Ghostscript imager requires that depth be a power of 2 or be 24,
 * so the actual allowed values are more limited.
 *      pgm, pgnm: 1, 2, 4, 8, 16.  [1-16]
 *      pgmraw, pgnmraw: 1, 2, 4, 8.  [1-8]
 *      ppm, pnm: 4(3x1), 8(3x2), 16(3x5), 24(3x8), 32(3x10).  [3-32]
 *      ppmraw, pnmraw: 4(3x1), 8(3x2), 16(3x5), 24(3x8).  [3-24]
 *      pkm, pkmraw: 4(4x1), 8(4x2), 16(4x4), 32(4x8).  [4-32]
 *      pksm, pksmraw: ibid.
 *      pam: 32 (CMYK), 4 (CMYK)
 */

/* Structure for P*M devices, which extend the generic printer device. */

#define MAX_COMMENT 70          /* max user-supplied comment */
struct gx_device_pbm_s {
    gx_device_common;
    gx_prn_device_common;
    /* Additional state for P*M devices */
    char magic;                 /* n for "Pn" */
    char comment[MAX_COMMENT + 1];      /* comment for head of file */
    byte is_raw;                /* 1 if raw format, 0 if plain */
    byte optimize;              /* 1 if optimization OK, 0 if not */
    byte uses_color;            /* 0 if image is black and white, */
                                /* 1 if gray (PGM or PPM only), */
                                /* 2 or 3 if colored (PPM only) */
    bool UsePlanarBuffer;       /* 0 if chunky buffer, 1 if planar */
    dev_proc_copy_alpha((*save_copy_alpha));
    dev_proc_begin_typed_image((*save_begin_typed_image));
};
typedef struct gx_device_pbm_s gx_device_pbm;

/* ------ The device descriptors ------ */

/*
 * Default X and Y resolution.
 */
#define X_DPI 72
#define Y_DPI 72

/* Macro for generating P*M device descriptors. */
#define pbm_prn_device(procs, dev_name, magic, is_raw, num_comp, depth, max_gray, max_rgb, optimize, x_dpi, y_dpi, print_page)\
{       prn_device_body(gx_device_pbm, procs, dev_name,\
          DEFAULT_WIDTH_10THS, DEFAULT_HEIGHT_10THS, x_dpi, y_dpi,\
          0, 0, 0, 0,\
          num_comp, depth, max_gray, max_rgb, max_gray + 1, max_rgb + 1,\
          print_page),\
        magic,\
         { 0 },\
        is_raw,\
        optimize,\
        0, 0, 0\
}

/* For all but PBM, we need our own color mapping and alpha procedures. */
static dev_proc_encode_color(pgm_encode_color);
static dev_proc_encode_color(pnm_encode_color);
static dev_proc_decode_color(pgm_decode_color);
static dev_proc_decode_color(ppm_decode_color);
static dev_proc_map_cmyk_color(pkm_map_cmyk_color);
static dev_proc_map_color_rgb(pkm_map_color_rgb);
static dev_proc_get_params(ppm_get_params);
static dev_proc_put_params(ppm_put_params);
static dev_proc_copy_alpha(pnm_copy_alpha);
static dev_proc_begin_typed_image(pnm_begin_typed_image);

/* We need to initialize uses_color when opening the device, */
/* and after each showpage. */
static dev_proc_open_device(ppm_open);
static dev_proc_open_device(pnmcmyk_open);
static dev_proc_output_page(ppm_output_page);

/* And of course we need our own print-page routines. */
static dev_proc_print_page(pbm_print_page);
static dev_proc_print_page(pgm_print_page);
static dev_proc_print_page(ppm_print_page);
static dev_proc_print_page(pkm_print_page);
static dev_proc_print_page(psm_print_page);
static dev_proc_print_page(psm_print_page);
static dev_proc_print_page(pam_print_page);
static dev_proc_print_page(pam4_print_page);
static dev_proc_print_page(pnmcmyk_print_page);

/* The device procedures */

static void
pbm_initialize_device_procs(gx_device *dev)
{
    gdev_prn_initialize_device_procs_mono(dev);

    set_dev_proc(dev, encode_color, gx_default_b_w_mono_encode_color);
    set_dev_proc(dev, decode_color, gx_default_b_w_mono_decode_color);
    set_dev_proc(dev, put_params, ppm_put_params);
    set_dev_proc(dev, output_page, ppm_output_page);
}

static void
ppm_initialize_device_procs(gx_device *dev)
{
    pbm_initialize_device_procs(dev);

    set_dev_proc(dev, get_params, ppm_get_params);
    set_dev_proc(dev, map_rgb_color, gx_default_rgb_map_rgb_color);
    set_dev_proc(dev, map_color_rgb, ppm_decode_color);
    set_dev_proc(dev, encode_color, gx_default_rgb_map_rgb_color);
    set_dev_proc(dev, decode_color, ppm_decode_color);
    set_dev_proc(dev, open_device, ppm_open);
}

static void
pgm_initialize_device_procs(gx_device *dev)
{
    pbm_initialize_device_procs(dev);

    set_dev_proc(dev, map_rgb_color, pgm_encode_color);
    set_dev_proc(dev, map_color_rgb, pgm_decode_color);
    set_dev_proc(dev, encode_color, pgm_encode_color);
    set_dev_proc(dev, decode_color, pgm_decode_color);
    set_dev_proc(dev, open_device, ppm_open);
}

static void
pnm_initialize_device_procs(gx_device *dev)
{
    ppm_initialize_device_procs(dev);

    set_dev_proc(dev, encode_color, pnm_encode_color);
    set_dev_proc(dev, decode_color, ppm_decode_color);
}

static void
pkm_initialize_device_procs(gx_device *dev)
{
    ppm_initialize_device_procs(dev);

    set_dev_proc(dev, map_rgb_color, NULL);
    set_dev_proc(dev, decode_color, cmyk_1bit_map_color_rgb);
    set_dev_proc(dev, encode_color, cmyk_1bit_map_cmyk_color);
}

static void
pam32_initialize_device_procs(gx_device *dev)
{
    ppm_initialize_device_procs(dev);

    set_dev_proc(dev, map_rgb_color, NULL);
    set_dev_proc(dev, map_color_rgb, cmyk_8bit_map_color_rgb);
    set_dev_proc(dev, map_cmyk_color, cmyk_8bit_map_cmyk_color);
    set_dev_proc(dev, decode_color, cmyk_8bit_map_color_cmyk);
    set_dev_proc(dev, encode_color, cmyk_8bit_map_cmyk_color);
}

static void
pam4_initialize_device_procs(gx_device *dev)
{
    ppm_initialize_device_procs(dev);

    set_dev_proc(dev, map_rgb_color, NULL);
    set_dev_proc(dev, map_color_rgb, NULL);
    set_dev_proc(dev, map_cmyk_color, cmyk_1bit_map_cmyk_color);
    set_dev_proc(dev, decode_color, cmyk_1bit_map_color_cmyk);
    set_dev_proc(dev, encode_color, cmyk_1bit_map_cmyk_color);
}

static void
pnmcmyk_initialize_device_procs(gx_device *dev)
{
    pam32_initialize_device_procs(dev);

    set_dev_proc(dev, open_device, pnmcmyk_open);
}

/* The device descriptors themselves */
const gx_device_pbm gs_pbm_device =
pbm_prn_device(pbm_initialize_device_procs, "pbm", '1', 0, 1, 1, 1, 0, 0,
               X_DPI, Y_DPI, pbm_print_page);
const gx_device_pbm gs_pbmraw_device =
pbm_prn_device(pbm_initialize_device_procs, "pbmraw", '4', 1, 1, 1, 1, 1, 0,
               X_DPI, Y_DPI, pbm_print_page);
const gx_device_pbm gs_pgm_device =
pbm_prn_device(pgm_initialize_device_procs, "pgm", '2', 0, 1, 8, 255, 0, 0,
               X_DPI, Y_DPI, pgm_print_page);
const gx_device_pbm gs_pgmraw_device =
pbm_prn_device(pgm_initialize_device_procs, "pgmraw", '5', 1, 1, 8, 255, 0, 0,
               X_DPI, Y_DPI, pgm_print_page);
const gx_device_pbm gs_pgnm_device =
pbm_prn_device(pgm_initialize_device_procs, "pgnm", '2', 0, 1, 8, 255, 0, 1,
               X_DPI, Y_DPI, pgm_print_page);
const gx_device_pbm gs_pgnmraw_device =
pbm_prn_device(pgm_initialize_device_procs, "pgnmraw", '5', 1, 1, 8, 255, 0, 1,
               X_DPI, Y_DPI, pgm_print_page);
const gx_device_pbm gs_ppm_device =
pbm_prn_device(ppm_initialize_device_procs, "ppm", '3', 0, 3, 24, 255, 255, 0,
               X_DPI, Y_DPI, ppm_print_page);
const gx_device_pbm gs_ppmraw_device =
pbm_prn_device(ppm_initialize_device_procs, "ppmraw", '6', 1, 3, 24, 255, 255, 0,
               X_DPI, Y_DPI, ppm_print_page);
const gx_device_pbm gs_pnm_device =
pbm_prn_device(pnm_initialize_device_procs, "pnm", '3', 0, 3, 24, 255, 255, 1,
               X_DPI, Y_DPI, ppm_print_page);
const gx_device_pbm gs_pnmraw_device =
pbm_prn_device(pnm_initialize_device_procs, "pnmraw", '6', 1, 3, 24, 255, 255, 1,
               X_DPI, Y_DPI, ppm_print_page);
const gx_device_pbm gs_pkm_device =
pbm_prn_device(pkm_initialize_device_procs, "pkm", '3', 0, 4, 4, 1, 1, 0,
               X_DPI, Y_DPI, pkm_print_page);
const gx_device_pbm gs_pkmraw_device =
pbm_prn_device(pkm_initialize_device_procs, "pkmraw", '6', 1, 4, 4, 1, 1, 0,
               X_DPI, Y_DPI, pkm_print_page);
const gx_device_pbm gs_pksm_device =
pbm_prn_device(pkm_initialize_device_procs, "pksm", '1', 0, 4, 4, 1, 1, 0,
               X_DPI, Y_DPI, psm_print_page);
const gx_device_pbm gs_pksmraw_device =
pbm_prn_device(pkm_initialize_device_procs, "pksmraw", '4', 1, 4, 4, 1, 1, 0,
               X_DPI, Y_DPI, psm_print_page);
const gx_device_pbm gs_pamcmyk32_device =
pbm_prn_device(pam32_initialize_device_procs, "pamcmyk32", '7', 1, 4, 32, 255, 255, 0,
               X_DPI, Y_DPI, pam_print_page);
const gx_device_pbm gs_pnmcmyk_device =
pbm_prn_device(pnmcmyk_initialize_device_procs, "pnmcmyk", '7', 1, 4, 32, 255, 255, 0, /* optimize false since this relies on GrayDetection */
               X_DPI, Y_DPI, pnmcmyk_print_page);	/* May output PGM, magic = 5 */
const gx_device_pbm gs_pamcmyk4_device =
pbm_prn_device(pam4_initialize_device_procs, "pamcmyk4", '7', 1, 4, 4, 1, 1, 0,
               X_DPI, Y_DPI, pam4_print_page);
/* Also keep the old device name so anyone using it won't be surprised */
const gx_device_pbm gs_pam_device =
pbm_prn_device(pam32_initialize_device_procs, "pam", '7', 1, 4, 32, 255, 255, 0,
               X_DPI, Y_DPI, pam_print_page);

/* Plan 9 bitmaps default to 100 dpi. */
const gx_device_pbm gs_plan9bm_device =
pbm_prn_device(pbm_initialize_device_procs, "plan9bm", '9', 1, 1, 1, 1, 1, 1,
               100, 100, pbm_print_page);

/* ------ Initialization ------ */

/* Set the copy_alpha and color mapping procedures if necessary. */
static void
ppm_set_dev_procs(gx_device * pdev)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;

    if (dev_proc(pdev, copy_alpha) != pnm_copy_alpha) {
        bdev->save_copy_alpha = dev_proc(pdev, copy_alpha);
        if (pdev->color_info.depth > 4)
            set_dev_proc(pdev, copy_alpha, pnm_copy_alpha);
    }
    if (dev_proc(pdev, begin_typed_image) != pnm_begin_typed_image) {
        bdev->save_begin_typed_image = dev_proc(pdev, begin_typed_image);
        set_dev_proc(pdev, begin_typed_image, pnm_begin_typed_image);
    }
    if (bdev->color_info.num_components == 4) {
        if (bdev->color_info.depth == 4) {
            set_dev_proc(pdev, map_color_rgb, cmyk_1bit_map_color_rgb);
            set_dev_proc(pdev, map_cmyk_color, cmyk_1bit_map_cmyk_color);
        } else if (bdev->magic == '7') {
            set_dev_proc(pdev, map_color_rgb, cmyk_8bit_map_color_rgb);
            set_dev_proc(pdev, map_cmyk_color, cmyk_8bit_map_cmyk_color);
        } else {
            set_dev_proc(pdev, map_color_rgb, pkm_map_color_rgb);
            set_dev_proc(pdev, map_cmyk_color, pkm_map_cmyk_color);
        }
    }
}

/*
 * Define a special open procedure that changes create_buf_device to use
 * a planar device.
 */

static int
ppm_open(gx_device * pdev)
{
    gx_device_pbm * bdev = (gx_device_pbm *)pdev;
    int code;

#ifdef TEST_PAD_AND_ALIGN
    pdev->pad = 5;
    pdev->log2_align_mod = 6;
#endif

    code = gdev_prn_open_planar(pdev, bdev->UsePlanarBuffer);
    while (pdev->child)
        pdev = pdev->child;

    bdev = (gx_device_pbm *)pdev;;

    if (code < 0)
        return code;
    pdev->color_info.separable_and_linear = GX_CINFO_SEP_LIN;
    set_linear_color_bits_mask_shift(pdev);
    bdev->uses_color = 0;
    ppm_set_dev_procs(pdev);
    return code;
}

/*
 * For pnmcmyk, we set GrayDection true by default. This may be overridden by
 * the default_put_params, but that's OK.
 */
static int
pnmcmyk_open(gx_device *pdev)
{
    pdev->icc_struct->graydetection = true;
    pdev->icc_struct->pageneutralcolor = true;   /* enable detection */

    return ppm_open(pdev);
}

/* Print a page, and reset uses_color if this is a showpage. */
static int
ppm_output_page(gx_device * pdev, int num_copies, int flush)
{
    /* Safe to start the page in the background */
    int code = gdev_prn_bg_output_page(pdev, num_copies, flush);
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;

    if (code < 0)
        return code;
    if (flush)
        bdev->uses_color = 0;
    return code;
}

/* ------ Color mapping routines ------ */

/* Map an RGB color to a PGM gray value. */
/* Keep track of whether the image is black-and-white or gray. */
static gx_color_index
pgm_encode_color(gx_device * pdev, const gx_color_value cv[])
{
    gx_color_value gray;
    gray = cv[0] * pdev->color_info.max_gray / gx_max_color_value;

    if (!(gray == 0 || gray == pdev->color_info.max_gray)) {
        gx_device_pbm * const bdev = (gx_device_pbm *)pdev;

        bdev->uses_color = 1;
    }
    return gray;
}

/* Map a PGM gray value back to an RGB color. */
static int
pgm_decode_color(gx_device * dev, gx_color_index color,
                  gx_color_value *pgray)
{
    gx_color_value gray =
    color * gx_max_color_value / dev->color_info.max_gray;

    pgray[0] = gray;
    return 0;
}

/*
 * Pre gs8.00 version of RGB mapping for 24-bit true (RGB) color devices
 * It is kept here for backwards comparibility since the gs8.00 version
 * has changed in functionality.  The new one requires that the device be
 * 'separable'.  This routine is logically separable but does not require
 * the various color_info fields associated with separability (comp_shift,
 * comp_bits, and comp_mask) be setup.
 */

static gx_color_index
gx_old_default_rgb_map_rgb_color(gx_device * dev,
                       gx_color_value r, gx_color_value g, gx_color_value b)
{
    if (dev->color_info.depth == 24)
        return gx_color_value_to_byte(b) +
            ((uint) gx_color_value_to_byte(g) << 8) +
            ((ulong) gx_color_value_to_byte(r) << 16);
    else {
        int bpc = dev->color_info.depth / 3;
        int drop = sizeof(gx_color_value) * 8 - bpc;

        return (((((gx_color_index)(r >> drop)) << bpc) + (g >> drop)) << bpc) + (b >> drop);
    }
}

/* Map an RGB color to a PPM color tuple. */
/* Keep track of whether the image is black-and-white, gray, or colored. */
static gx_color_index
pnm_encode_color(gx_device * pdev, const gx_color_value cv[])
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;
    gx_color_index color =
            gx_old_default_rgb_map_rgb_color(pdev, cv[0], cv[1], cv[2]);
    uint bpc = pdev->color_info.depth / 3;
    gx_color_index mask =
        ((gx_color_index)1 << (pdev->color_info.depth - bpc)) - 1;
    if (!(((color >> bpc) ^ color) & mask)) { /* gray shade */
        if (color != 0 && (~color & mask))
            bdev->uses_color |= 1;
    } else                      /* color */
        bdev->uses_color = 2;
    return color;
}

/* Map a PPM color tuple back to an RGB color. */
static int
ppm_decode_color(gx_device * dev, gx_color_index color,
                 gx_color_value prgb[])
{
    uint bitspercolor = dev->color_info.depth / 3;
    uint colormask = (1 << bitspercolor) - 1;
    uint max_rgb = dev->color_info.max_color;

    prgb[0] = ((color >> (bitspercolor * 2)) & colormask) *
        (ulong) gx_max_color_value / max_rgb;
    prgb[1] = ((color >> bitspercolor) & colormask) *
        (ulong) gx_max_color_value / max_rgb;
    prgb[2] = (color & colormask) *
        (ulong) gx_max_color_value / max_rgb;
    return 0;
}

/* Map a CMYK color to a pixel value. */
static gx_color_index
pkm_map_cmyk_color(gx_device * pdev, const gx_color_value cv[])
{
    uint bpc = pdev->color_info.depth >> 2;
    uint max_value = pdev->color_info.max_color;
    uint cc = cv[0] * max_value / gx_max_color_value;
    uint mc = cv[1] * max_value / gx_max_color_value;
    uint yc = cv[2] * max_value / gx_max_color_value;
    uint kc = cv[3] * max_value / gx_max_color_value;
    gx_color_index color =
        ((((((gx_color_index)cc << bpc) + mc) << bpc) + yc) << bpc) + kc;

    return (color == gx_no_color_index ? color ^ 1 : color);
}

/* Map a CMYK pixel value to RGB. */
static int
pkm_map_color_rgb(gx_device * dev, gx_color_index color, gx_color_value rgb[3])
{
    int bpc = dev->color_info.depth >> 2;
    gx_color_index cshift = color;
    uint mask = (1 << bpc) - 1;
    uint k = cshift & mask;
    uint y = (cshift >>= bpc) & mask;
    uint m = (cshift >>= bpc) & mask;
    uint c = cshift >> bpc;
    uint max_value = dev->color_info.max_color;
    uint not_k = max_value - k;

#define CVALUE(c)\
  ((gx_color_value)((ulong)(c) * gx_max_color_value / max_value))
        /* We use our improved conversion rule.... */
        rgb[0] = CVALUE((max_value - c) * not_k / max_value);
    rgb[1] = CVALUE((max_value - m) * not_k / max_value);
    rgb[2] = CVALUE((max_value - y) * not_k / max_value);
#undef CVALUE
    return 0;
}

/* Augment get/put_params to add UsePlanarBuffer */

static int
ppm_get_params(gx_device * pdev, gs_param_list * plist)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;
    int code;

    code = gdev_prn_get_params_planar(pdev, plist, &bdev->UsePlanarBuffer);
    if (code < 0) return code;
    code = param_write_null(plist, "OutputIntent");
    return code;
}

static int
ppm_put_params(gx_device * pdev, gs_param_list * plist)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;
    gx_device_color_info save_info;
    int ncomps = pdev->color_info.num_components;
    int bpc = pdev->color_info.depth / ncomps;
    int ecode = 0;
    int code;
    long v;
    gs_param_string_array intent;
    const char *vname;

    if ((code = param_read_string_array(plist, "OutputIntent", &intent)) == 0) {
        /* This device does not use the OutputIntent parameter.
           We include this code just as a sample how to handle it.
           The PDF interpreter extracts OutputIntent from a PDF file and sends it to here,
           if a device includes it in the .getdeviceparams response.
           This device does include due to ppm_get_params implementation.
           ppm_put_params must handle it (and ingore it) against 'rangecheck'.
         */
        static const bool debug_print_OutputIntent = false;

        if (debug_print_OutputIntent) {
            int i, j;

            dmlprintf1(pdev->memory, "%d strings:\n", intent.size);
            for (i = 0; i < intent.size; i++) {
                const gs_param_string *s = &intent.data[i];
                dmlprintf2(pdev->memory, "  %d: size %d:", i, s->size);
                if (i < 4) {
                    for (j = 0; j < s->size; j++)
                        dmlprintf1(pdev->memory, "%c", s->data[j]);
                } else {
                    for (j = 0; j < s->size; j++)
                        dmlprintf1(pdev->memory, " %02x", s->data[j]);
                }
                dmlprintf(pdev->memory, "\n");
            }
        }
    }
    save_info = pdev->color_info;
    if ((code = param_read_long(plist, (vname = "GrayValues"), &v)) != 1 ||
        (code = param_read_long(plist, (vname = "RedValues"), &v)) != 1 ||
        (code = param_read_long(plist, (vname = "GreenValues"), &v)) != 1 ||
        (code = param_read_long(plist, (vname = "BlueValues"), &v)) != 1
        ) {
        if (code < 0)
            ecode = code;
        else if (v < 2 || v > (bdev->is_raw || ncomps > 1 ? 256 : 65536L))
            param_signal_error(plist, vname,
                               ecode = gs_error_rangecheck);
        else if (v == 2)
            bpc = 1;
        else if (v <= 4)
            bpc = 2;
        else if (v <= 16)
            bpc = 4;
        else if (v <= 32 && ncomps == 3)
            bpc = 5;
        else if (v <= 256)
            bpc = 8;
        else
            bpc = 16;
        if (ecode >= 0) {
            static const byte depths[4][16] =
            {
                {1, 2, 0, 4, 0, 0, 0, 8, 0, 0, 0, 0, 0, 0, 0, 16},
                {0},
                {4, 8, 0, 16, 16, 0, 0, 24},
                {4, 8, 0, 16, 0, 0, 0, 32},
            };

            pdev->color_info.depth = depths[ncomps - 1][bpc - 1];
            pdev->color_info.max_gray = pdev->color_info.max_color =
                (pdev->color_info.dither_grays =
                 pdev->color_info.dither_colors = (int)v) - 1;
        }
    }
    if ((code = ecode) < 0 ||
        (code = gdev_prn_put_params_planar(pdev, plist, &bdev->UsePlanarBuffer)) < 0
        )
        pdev->color_info = save_info;
    ppm_set_dev_procs(pdev);
    return code;
}

/* Copy an alpha map, noting whether we may generate some non-black/white */
/* colors through blending. */
static int
pnm_copy_alpha(gx_device * pdev, const byte * data, int data_x,
           int raster, gx_bitmap_id id, int x, int y, int width, int height,
               gx_color_index color, int depth)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;

    if (pdev->color_info.depth < 24 ||
        (color >> 8) == (color & 0xffff)
        )
        bdev->uses_color |= 1;
    else
        bdev->uses_color |= 2;
    return (*bdev->save_copy_alpha) (pdev, data, data_x, raster, id,
                                     x, y, width, height, color, depth);
}

/* Begin processing an image, noting whether we may generate some */
/* non-black/white colors in the process. */
static int
pnm_begin_typed_image(gx_device *dev,
                      const gs_gstate *pgs, const gs_matrix *pmat,
                      const gs_image_common_t *pim, const gs_int_rect *prect,
                      const gx_drawing_color *pdcolor,
                      const gx_clip_path *pcpath,
                      gs_memory_t *memory, gx_image_enum_common_t **pinfo)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)dev;
    bool has_gray_icc;

    /* Conservatively guesses whether this operation causes color usage
       that might not be otherwise captured by ppm_map_color_rgb. */
    if (pim && pim->type) {
        switch (pim->type->index) {
        case 1: case 3: case 4: {
            /* Use colorspace to handle image types 1,3,4 */
            const gs_pixel_image_t *pim1 = (const gs_pixel_image_t *)pim;

            if (pim1->ColorSpace) {
                has_gray_icc = false;
                if (pim1->ColorSpace->cmm_icc_profile_data) {
                    if (pim1->ColorSpace->cmm_icc_profile_data->num_comps == 1) {
                        has_gray_icc = true;
                    }
                }
                if (gs_color_space_get_index(pim1->ColorSpace) ==
                            gs_color_space_index_DeviceGray || has_gray_icc) {
                    if (pim1->BitsPerComponent > 1)
                        bdev->uses_color |= 1;
                } else
                    bdev->uses_color = 2;
            }
            break;
        }
        default:
            /* Conservatively handles other image types */
            bdev->uses_color = 2;
        }
    }
    /* Forward to saved routine */
    return (*bdev->save_begin_typed_image)(dev, pgs, pmat, pim, prect,
                                           pdcolor, pcpath, memory, pinfo);
}

/* ------ Internal routines ------ */

/* NOP row processing function used when no output */
static int nop_row_proc(gx_device_printer *pdev, byte *data, int len, gp_file *f)
{
    return 0;
}

/* Print a page using a given row printing routine. */
static int
pbm_print_page_loop(gx_device_printer * pdev, char magic, gp_file * pstream,
             int (*row_proc) (gx_device_printer *, byte *, int, gp_file *))
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;
    uint raster = gdev_prn_raster_chunky(pdev);
    byte *data = gs_alloc_bytes(pdev->memory, raster, "pbm_print_page_loop");
    int lnum = 0;
    int code = 0;
    int output_is_nul = !strncmp(pdev->fname, "nul:", min(strlen(pdev->fname), 4)) ||
        !strncmp(pdev->fname, "/dev/null", min(strlen(pdev->fname), 9));

    if (data == 0)
        return_error(gs_error_VMerror);
    if (!output_is_nul) {
        /* Hack.  This should be done in the callers.  */
        if (magic == '9') {
            if (gp_fprintf(pstream, "%11d %11d %11d %11d %11d ",
                0, 0, 0, pdev->width, pdev->height) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
        } else if (magic == '7') {
            int ncomps = pdev->color_info.num_components;
            if (gp_fprintf(pstream, "P%c\n", magic) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
            if (gp_fprintf(pstream, "WIDTH %d\n", pdev->width) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
            if (gp_fprintf(pstream, "HEIGHT %d\n", pdev->height) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
            if (gp_fprintf(pstream, "DEPTH %d\n", ncomps) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
            if (gp_fprintf(pstream, "MAXVAL %d\n", 255) < 0) { /* force MAXVAL to 255 */
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
            if (gp_fprintf(pstream, "TUPLTYPE %s\n",
                (ncomps == 4) ? "CMYK" :
                ((ncomps == 3) ? "RGB" : "GRAYSCALE")) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
            if (bdev->comment[0]) {
                if (gp_fprintf(pstream, "# %s\n", bdev->comment) < 0) {
                    code = gs_note_error(gs_error_ioerror);
                    goto punt;
                }
            } else {
                if (gp_fprintf(pstream, "# Image generated by %s\n", gs_product) < 0) {
                    code = gs_note_error(gs_error_ioerror);
                    goto punt;
                }
            }
            if (gp_fprintf(pstream, "ENDHDR\n") < 0) {
                 code = gs_note_error(gs_error_ioerror);
                 goto punt;
            }
        } else {
            if (gp_fprintf(pstream, "P%c\n", magic) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
            if (bdev->comment[0]) {
                if (gp_fprintf(pstream, "# %s\n", bdev->comment) < 0) {
                    code = gs_note_error(gs_error_ioerror);
                    goto punt;
                }
            } else {
                if (gp_fprintf(pstream, "# Image generated by %s (device=%s)\n",
                        gs_product, pdev->dname) < 0) {
                    code = gs_note_error(gs_error_ioerror);
                    goto punt;
                }
            }
            if (gp_fprintf(pstream, "%d %d\n", pdev->width, pdev->height) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
        }
        switch (magic) {
        case '1':               /* pbm */
        case '4':               /* pbmraw */
        case '7':               /* pam */
        case '9':               /* plan9bm */
            break;
        case '3':               /* pkm */
        case '6':               /* pkmraw */
            if (gp_fprintf(pstream, "%d\n", 255) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
            break;
        default:
            if (gp_fprintf(pstream, "%d\n", pdev->color_info.max_gray) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
        }
    }
    if (output_is_nul)
        row_proc = nop_row_proc;
    for (; lnum < pdev->height; lnum++) {
        byte *row;

        code = gdev_prn_get_bits(pdev, lnum, data, &row);
        if (code < 0)
            break;
        code = (*row_proc) (pdev, row, pdev->color_info.depth, pstream);
        if (code < 0)
            break;
    }
  punt:
    gs_free_object(pdev->memory, data, "pbm_print_page_loop");
    return (code < 0 ? code : 0);
}

/* ------ Individual page printing routines ------ */

/* Print a monobit page. */
static int
pbm_print_row(gx_device_printer * pdev, byte * data, int depth,
              gp_file * pstream)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;

    if (bdev->is_raw) {
        uint n = (pdev->width + 7) >> 3;

        if (gp_fwrite(data, 1, n, pstream) != n)
            return_error(gs_error_ioerror);
    } else {
        byte *bp;
        uint x, mask;

        for (bp = data, x = 0, mask = 0x80; x < pdev->width;) {
            if (gp_fputc((*bp & mask ? '1' : '0'), pstream) == EOF)
                return_error(gs_error_ioerror);
            if (++x == pdev->width || !(x & 63)) {
                if (gp_fputc('\n', pstream) == EOF)
                    return_error(gs_error_ioerror);
            }
            if ((mask >>= 1) == 0)
                bp++, mask = 0x80;
        }
    }
    return 0;
}
static int
pbm_print_page(gx_device_printer * pdev, gp_file * pstream)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;

    return pbm_print_page_loop(pdev, bdev->magic, pstream, pbm_print_row);
}

/* Print a gray-mapped page. */
static int
pgm_print_row(gx_device_printer * pdev, byte * data, int depth,
              gp_file * pstream)
{                               /* Note that bpp <= 8 for raw format, bpp <= 16 for plain. */
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;
    uint mask = (1 << depth) - 1;
    /*
     * If we're writing planes for a CMYK device, we have 0 = white,
     * mask = black, which is the opposite of the pgm convention.
     */
    uint invert = (pdev->color_info.polarity == GX_CINFO_POLARITY_SUBTRACTIVE);
    byte *bp;
    uint x;
    int shift;

    if (bdev->is_raw && depth == 8) {
        if (invert) {
            for (bp = data, x = 0; x < pdev->width; bp++, x++) {
                if (gp_fputc((byte)~*bp, pstream) == EOF)
                    return_error(gs_error_ioerror);
            }
        } else {
            if (gp_fwrite(data, 1, pdev->width, pstream) != pdev->width)
                return_error(gs_error_ioerror);
        }
    } else
        for (bp = data, x = 0, shift = 8 - depth; x < pdev->width;) {
            uint pixel;

            if (shift < 0) {    /* bpp = 16 */
                pixel = ((uint) * bp << 8) + bp[1];
                bp += 2;
            } else {
                pixel = (*bp >> shift) & mask;
                if ((shift -= depth) < 0)
                    bp++, shift += 8;
            }
            ++x;
            pixel ^= invert;
            if (bdev->is_raw) {
                if (gp_fputc(pixel, pstream) == EOF)
                    return_error(gs_error_ioerror);
            } else {
                if (gp_fprintf(pstream, "%d%c", pixel,
                        (x == pdev->width || !(x & 15) ? '\n' : ' ')) < 0)
                    return_error(gs_error_ioerror);
            }
        }
    return 0;
}
static int
pxm_pbm_print_row(gx_device_printer * pdev, byte * data, int depth,
                  gp_file * pstream)
{                               /* Compress a PGM or PPM row to a PBM row. */
    /* This doesn't have to be very fast. */
    /* Note that we have to invert the data as well. */
    int delta = (depth + 7) >> 3;
    byte *src = data + delta - 1;       /* always big-endian */
    byte *dest = data;
    int x;
    byte out_mask = 0x80;
    byte out = 0;

    if (depth >= 8) {           /* One or more bytes per source pixel. */
        for (x = 0; x < pdev->width; x++, src += delta) {
            if (!(*src & 1))
                out |= out_mask;
            out_mask >>= 1;
            if (!out_mask)
                out_mask = 0x80,
                    *dest++ = out,
                    out = 0;
        }
    } else {                    /* Multiple source pixels per byte. */
        byte in_mask = 0x100 >> depth;

        for (x = 0; x < pdev->width; x++) {
            if (!(*src & in_mask))
                out |= out_mask;
            in_mask >>= depth;
            if (!in_mask)
                in_mask = 0x100 >> depth,
                    src++;
            out_mask >>= 1;
            if (!out_mask)
                out_mask = 0x80,
                    *dest++ = out,
                    out = 0;
        }
    }
    if (out_mask != 0x80)
        *dest = out;
    return pbm_print_row(pdev, data, 1, pstream);
}
static int
pgm_print_page(gx_device_printer * pdev, gp_file * pstream)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;

    return (bdev->uses_color == 0 && bdev->optimize ?
            pbm_print_page_loop(pdev, (char)((int)bdev->magic - 1), pstream,
                                pxm_pbm_print_row) :
            pbm_print_page_loop(pdev, bdev->magic, pstream,
                                pgm_print_row));
}

/* Print a color-mapped page. */
static int
ppgm_print_row(gx_device_printer * pdev, byte * data, int depth,
               gp_file * pstream, bool color)
{                               /* If color=false, write only one value per pixel; */
    /* if color=true, write 3 values per pixel. */
    /* Note that depth <= 24 for raw format, depth <= 32 for plain. */
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;
    uint bpe = depth / 3;       /* bits per r/g/b element */
    uint mask = (1 << bpe) - 1;
    byte *bp;
    uint x;
    uint eol_mask = (color ? 7 : 15);
    int shift;

    if (bdev->is_raw && depth == 24 && color) {
        uint n = pdev->width * (depth / 8);

        if (gp_fwrite(data, 1, n, pstream) != n)
            return_error(gs_error_ioerror);
    } else {
        for (bp = data, x = 0, shift = 8 - depth; x < pdev->width;) {
            bits32 pixel = 0;
            uint r, g, b;

            switch (depth >> 3) {
                case 4:
                    pixel = (bits32) * bp << 24;
                    bp++;
                    /* falls through */
                case 3:
                    pixel += (bits32) * bp << 16;
                    bp++;
                    /* falls through */
                case 2:
                    pixel += (uint) * bp << 8;
                    bp++;
                    /* falls through */
                case 1:
                    pixel += *bp;
                    bp++;
                    break;
                case 0: /* bpp == 4, bpe == 1 */
                    pixel = *bp >> shift;
                    if ((shift -= depth) < 0)
                        bp++, shift += 8;
                    break;
            }
            ++x;
            b = pixel & mask;
            pixel >>= bpe;
            g = pixel & mask;
            pixel >>= bpe;
            r = pixel & mask;
            if (bdev->is_raw) {
                if (color) {
                    if (gp_fputc(r, pstream) == EOF)
                        return_error(gs_error_ioerror);
                    if (gp_fputc(g, pstream) == EOF)
                        return_error(gs_error_ioerror);
                }
                if (gp_fputc(b, pstream) == EOF)
                    return_error(gs_error_ioerror);
            } else {
                if (color) {
                    if (gp_fprintf(pstream, "%d %d ", r, g) < 0)
                        return_error(gs_error_ioerror);
                }
                if (gp_fprintf(pstream, "%d%c", b,
                        (x == pdev->width || !(x & eol_mask) ?
                         '\n' : ' ')) < 0)
                    return_error(gs_error_ioerror);
            }
        }
    }
    return 0;
}
static int
ppm_print_row(gx_device_printer * pdev, byte * data, int depth,
              gp_file * pstream)
{
    return ppgm_print_row(pdev, data, depth, pstream, true);
}
static int
ppm_pgm_print_row(gx_device_printer * pdev, byte * data, int depth,
                  gp_file * pstream)
{
    return ppgm_print_row(pdev, data, depth, pstream, false);
}
static int
ppm_print_page(gx_device_printer * pdev, gp_file * pstream)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;

    return (bdev->uses_color >= 2 || !bdev->optimize ?
            pbm_print_page_loop(pdev, bdev->magic, pstream,
                                ppm_print_row) :
            bdev->uses_color == 1 ?
            pbm_print_page_loop(pdev, (char)((int)bdev->magic - 1), pstream,
                                ppm_pgm_print_row) :
            pbm_print_page_loop(pdev, (char)((int)bdev->magic - 2), pstream,
                                pxm_pbm_print_row));
}

static int
pam_print_row(gx_device_printer * pdev, byte * data, int depth,
               gp_file * pstream)
{
    if (depth == 32) {
        uint n = pdev->width * (depth / 8);

        if (gp_fwrite(data, 1, n, pstream) != n)
            return_error(gs_error_ioerror);
    }
    return 0;
}

static int
pam_print_page(gx_device_printer * pdev, gp_file * pstream)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;

    return pbm_print_page_loop(pdev, bdev->magic, pstream,
                                pam_print_row);
}

static int
pnmcmyk_print_page(gx_device_printer *pdev, gp_file *pstream)
{
    if (pdev->icc_struct->graydetection == true && pdev->icc_struct->pageneutralcolor == true) {
        /* Here we need to convert the data from CMYK to K (gray) then print */
        gx_device_pbm * const bdev = (gx_device_pbm *)pdev;
        uint raster = gdev_prn_raster_chunky(pdev);	/* enough space for the CMYK data */
        byte *data = gs_alloc_bytes(pdev->memory, raster, "pbm_print_page_loop");
        int lnum = 0;
        int code = 0;
        int output_is_nul = !strncmp(pdev->fname, "nul:", min(strlen(pdev->fname), 4)) ||
            !strncmp(pdev->fname, "/dev/null", min(strlen(pdev->fname), 9));
        int (*row_proc) (gx_device_printer *, byte *, int, gp_file *);

        if (data == NULL)
            return_error(gs_error_VMerror);
        if (!output_is_nul) {
            if (gp_fprintf(pstream, "P5\n") < 0) {	/* PGM raw */
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
            if (bdev->comment[0]) {
                if (gp_fprintf(pstream, "# %s\n", bdev->comment) < 0) {
                    code = gs_note_error(gs_error_ioerror);
                    goto punt;
                }
            } else {
                if (gp_fprintf(pstream, "# Image generated by %s (device=%s)\n",
                        gs_product, pdev->dname) < 0) {
                    code = gs_note_error(gs_error_ioerror);
                    goto punt;
                }
            }
            if (gp_fprintf(pstream, "%d %d\n", pdev->width, pdev->height) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
            if (gp_fprintf(pstream, "255\n") < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
            row_proc = pgm_print_row;
        } else
            row_proc = nop_row_proc;


        for (; lnum < pdev->height; lnum++) {
            byte *row, *row_end;
            byte *pcmyk, *pgray;		/* scan pointers through the row */

            code = gdev_prn_get_bits(pdev, lnum, data, &row);
            if (code < 0)
                break;
            /* convert the CMYK to Gray */
            pgray = row;			/* destination for converted color */
            row_end = row + (4 * pdev->width);
            for (pcmyk = row; pcmyk < row_end;) {
                int32_t cmy;
                byte k;

                /* For now we assume that the CMYK may have gone through an ICC profile */
                /* so we do a more complex conversion from CMYK to K. If we are using   */
                /* FastColor, we may be able to do this more efficiently.               */
                cmy  = ((255 - *pcmyk++) * lum_red_weight);
                cmy += ((255 - *pcmyk++) * lum_green_weight);
                cmy += ((255 - *pcmyk++) * lum_blue_weight);
                cmy += (lum_all_weights / 2);
                cmy /= lum_all_weights;

                k = *pcmyk++;
                if (k > cmy)
                    k = 0;		/* additive black */
                else
                    k = cmy - k;	/* additive gray */
                *pgray++ = k;		/* store it */
            }
            /* we converted to normal "additive" gray (white == 1) so set */
            /* the color_info.polarity so that pgm_print_row doesn't invert */
            pdev->color_info.polarity = GX_CINFO_POLARITY_ADDITIVE;
            code = (*row_proc) (pdev, row, 8, pstream);
            pdev->color_info.polarity = GX_CINFO_POLARITY_SUBTRACTIVE; /* restore actual polarity */
            if (code < 0)
                break;
        }
        punt:
        gs_free_object(pdev->memory, data, "pbm_print_page_loop");
        return (code < 0 ? code : 0);
    }
    /* otherwise, just spit out the CMYK 32-bit PAM format */
    return pam_print_page(pdev, pstream);
}

static int
pam4_print_row(gx_device_printer * pdev, byte * data, int depth,
               gp_file * pstream)
{
    int w, s;
    if (depth == 4) {
        for (w = pdev->width; w > 0;) {
            byte C = *data++;
            for (s = 7; s >= 0; s -= 4)
            {
                gp_fputc(((C>>s    )&1)*0xff, pstream);
                gp_fputc(((C>>(s-1))&1)*0xff, pstream);
                gp_fputc(((C>>(s-2))&1)*0xff, pstream);
                gp_fputc(((C>>(s-3))&1)*0xff, pstream);
                w--;
                if (w == 0)
                    break;
            }
        }
    }
    return 0;
}

static int
pam4_print_page(gx_device_printer * pdev, gp_file * pstream)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;

    return pbm_print_page_loop(pdev, bdev->magic, pstream,
                               pam4_print_row);
}

/* Print a faux CMYK page. */
/* Print a row where each pixel occupies 4 bits (depth == 4). */
/* In this case, we also know pdev->color_info.max_color == 1. */
static int
pkm_print_row_4(gx_device_printer * pdev, byte * data, int depth,
                gp_file * pstream)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;
    byte *bp;
    uint x;
    byte rv[16], gv[16], bv[16], i;

    /* Precompute all the possible pixel values. */
    for (i = 0; i < 16; ++i) {
        gx_color_value rgb[3];

        cmyk_1bit_map_color_rgb((gx_device *)pdev, (gx_color_index)i, rgb);
        rv[i] = rgb[0] / gx_max_color_value * 0xff;
        gv[i] = rgb[1] / gx_max_color_value * 0xff;
        bv[i] = rgb[2] / gx_max_color_value * 0xff;
    }
    /*
     * Contrary to what the documentation implies, gcc compiles putc
     * as a procedure call.  This is ridiculous, but since we can't
     * change it, we buffer groups of pixels ourselves and use fwrite.
     */
    if (bdev->is_raw) {
#ifdef PACIFY_VALGRIND
        if ((pdev->width & 1) != 0) {
            data[pdev->width>>1] &= 0xf0;
        }
#endif
        for (bp = data, x = 0; x < pdev->width;) {
            byte raw[50 * 3];   /* 50 is arbitrary, but must be even */
            int end = min(x + sizeof(raw) / 3, pdev->width);
            byte *outp = raw;

            for (; x < end; bp++, outp += 6, x += 2) {
                uint b = *bp;
                uint pixel = b >> 4;

                outp[0] = rv[pixel], outp[1] = gv[pixel], outp[2] = bv[pixel];
                pixel = b & 0xf;
                outp[3] = rv[pixel], outp[4] = gv[pixel], outp[5] = bv[pixel];
            }
            /* x might overshoot the width by 1 pixel. */
            if (x > end)
                outp -= 3;
            if (gp_fwrite(raw, 1, outp - raw, pstream) != outp - raw)
                return_error(gs_error_ioerror);
        }
    } else {
        int shift;

        for (bp = data, x = 0, shift = 4; x < pdev->width;) {
            int pixel = (*bp >> shift) & 0xf;

            shift ^= 4;
            bp += shift >> 2;
            ++x;
            if (gp_fprintf(pstream, "%d %d %d%c", rv[pixel], gv[pixel], bv[pixel],
                    (x == pdev->width || !(x & 7) ?
                     '\n' : ' ')) < 0)
                return_error(gs_error_ioerror);
        }
    }
    return 0;
}
/* Print a row where each pixel occupies 1 or more bytes (depth >= 8). */
/* Note that the output is scaled up to 255 max value.                 */
static int
pkm_print_row(gx_device_printer * pdev, byte * data, int depth,
              gp_file * pstream)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;
    byte *bp;
    uint x;

    for (bp = data, x = 0; x < pdev->width;) {
        bits32 pixel = 0;
        gx_color_value rgb[3];
        uint r, g, b;

        switch (depth >> 3) {
            case 4:
                pixel = (bits32) * bp << 24;
                bp++;
                /* falls through */
            case 3:
                pixel += (bits32) * bp << 16;
                bp++;
                /* falls through */
            case 2:
                pixel += (uint) * bp << 8;
                bp++;
                /* falls through */
            case 1:
                pixel += *bp;
                bp++;
        }
        ++x;
        pkm_map_color_rgb((gx_device *) pdev, pixel, rgb);
        r = rgb[0] * 0xff / gx_max_color_value;
        g = rgb[1] * 0xff / gx_max_color_value;
        b = rgb[2] * 0xff / gx_max_color_value;
        if (bdev->is_raw) {
            if (gp_fputc(r, pstream) == EOF)
                return_error(gs_error_ioerror);
            if (gp_fputc(g, pstream) == EOF)
                return_error(gs_error_ioerror);
            if (gp_fputc(b, pstream) == EOF)
                return_error(gs_error_ioerror);
        } else {
            if (gp_fprintf(pstream, "%d %d %d%c", r, g, b,
                    (x == pdev->width || !(x & 7) ?
                     '\n' : ' ')) < 0)
                return_error(gs_error_ioerror);
        }
    }
    return 0;
}
static int
pkm_print_page(gx_device_printer * pdev, gp_file * pstream)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;

    return pbm_print_page_loop(pdev, bdev->magic, pstream,
                               (pdev->color_info.depth < 8 ?
                                pkm_print_row_4 :
                                pkm_print_row));
}

/* Print individual separations on a single file. */
static int
psm_print_page(gx_device_printer * pdev, gp_file * pstream)
{
    gx_device_pbm * const bdev = (gx_device_pbm *)pdev;
    /*
     * Allocate a large enough buffer for full pixels, on the theory that we
     * don't know how many bits will be allocated to each component.  (This
     * is for didactic purposes only: we know perfectly well that each
     * component will have 1/N of the bits.)
     */
    uint max_raster = bitmap_raster(pdev->width * pdev->color_info.depth);
    byte *data = gs_alloc_bytes(pdev->memory, max_raster, "pksm_print_page");
    int code = 0;
    unsigned char plane;

    if (data == 0)
        return_error(gs_error_VMerror);
    for (plane = 0; plane < pdev->color_info.num_components; ++plane) {
        int lnum, band_end;
        /*
         * The following initialization is unnecessary: lnum == band_end on
         * the first pass through the loop below, so marked will always be
         * set before it is used.  We initialize marked solely to suppress
         * bogus warning messages from certain compilers.
         */
        gx_color_index marked = 0;
        gx_render_plane_t render_plane;
        int plane_depth;
        int plane_shift;
        gx_color_index plane_mask;
        int raster;

        gx_render_plane_init(&render_plane, (gx_device *)pdev, plane);
        plane_depth = render_plane.depth;
        plane_shift = render_plane.shift;
        plane_mask = ((gx_color_index)1 << plane_depth) - 1;
        raster = bitmap_raster(pdev->width * plane_depth);
        if (gp_fprintf(pstream, "P%c\n", bdev->magic + (plane_depth > 1)) < 0) {
            code = gs_note_error(gs_error_ioerror);
            goto punt;
        }
        if (bdev->comment[0]) {
            if (gp_fprintf(pstream, "# %s\n", bdev->comment) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
        } else {
            if (gp_fprintf(pstream, "# Image generated by %s (device=%s)\n",
                    gs_product, pdev->dname) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
        }
        if (gp_fprintf(pstream, "%d %d\n", pdev->width, pdev->height) < 0) {
            code = gs_note_error(gs_error_ioerror);
            goto punt;
        }
        if (plane_depth > 1) {
            if (gp_fprintf(pstream, "%d\n", pdev->color_info.max_gray) < 0) {
                code = gs_note_error(gs_error_ioerror);
                goto punt;
            }
        }
        for (lnum = band_end = 0; lnum < pdev->height; lnum++) {
            byte *row;

            if (lnum == band_end) {
                gx_color_usage_t color_usage;
                int band_start;
                int band_height =
                    gdev_prn_color_usage((gx_device *)pdev, lnum, 1,
                                         &color_usage, &band_start);

                band_end = band_start + band_height;
                marked = color_usage.or & (plane_mask << plane_shift);
                if (!marked)
                    memset(data, 0, raster);
#ifdef DEBUG
                if (plane == 0)
                    if_debug4m(':', pdev->memory,
                               "[:]%4d - %4d mask = 0x%lx, slow_rop = %d\n",
                               lnum, band_end - 1, (ulong)color_usage.or,
                               color_usage.slow_rop);
#endif
            }
            if (marked) {
                gx_render_plane_t render_plane;
                uint actual_raster;

                render_plane.index = plane;
                code = gdev_prn_get_lines(pdev, lnum, 1, data, raster,
                                          &row, &actual_raster,
                                          &render_plane);
                if (code < 0)
                    break;
            } else
                row = data;
            code =
                (plane_depth == 1 ?
                 pbm_print_row(pdev, row, plane_depth, pstream) :
                 pgm_print_row(pdev, row, plane_depth, pstream));
            if (code < 0)
                break;
        }
    }
  punt:
    gs_free_object(pdev->memory, data, "pksm_print_page");
    return (code < 0 ? code : 0);
}