blob: b7cd425ce5998b04212c593d661ee2db53b89693 [file] [log] [blame]
/*
* rdppm.c
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1991-1997, Thomas G. Lane.
* Modified 2009 by Bill Allombert, Guido Vollbeding.
* libjpeg-turbo Modifications:
* Copyright (C) 2015-2017, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
* file.
*
* This file contains routines to read input images in PPM/PGM format.
* The extended 2-byte-per-sample raw PPM/PGM formats are supported.
* The PBMPLUS library is NOT required to compile this software
* (but it is highly useful as a set of PPM image manipulation programs).
*
* These routines may need modification for non-Unix environments or
* specialized applications. As they stand, they assume input from
* an ordinary stdio stream. They further assume that reading begins
* at the start of the file; start_input may need work if the
* user interface has already read some data (e.g., to determine that
* the file is indeed PPM format).
*/
#include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */
#include "cmyk.h"
#ifdef PPM_SUPPORTED
/* Portions of this code are based on the PBMPLUS library, which is:
**
** Copyright (C) 1988 by Jef Poskanzer.
**
** Permission to use, copy, modify, and distribute this software and its
** documentation for any purpose and without fee is hereby granted, provided
** that the above copyright notice appear in all copies and that both that
** copyright notice and this permission notice appear in supporting
** documentation. This software is provided "as is" without express or
** implied warranty.
*/
/* Macros to deal with unsigned chars as efficiently as compiler allows */
#ifdef HAVE_UNSIGNED_CHAR
typedef unsigned char U_CHAR;
#define UCH(x) ((int) (x))
#else /* !HAVE_UNSIGNED_CHAR */
#ifdef __CHAR_UNSIGNED__
typedef char U_CHAR;
#define UCH(x) ((int) (x))
#else
typedef char U_CHAR;
#define UCH(x) ((int) (x) & 0xFF)
#endif
#endif /* HAVE_UNSIGNED_CHAR */
#define ReadOK(file,buffer,len) (JFREAD(file,buffer,len) == ((size_t) (len)))
static int alpha_index[JPEG_NUMCS] = {
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 3, 3, 0, 0, -1
};
/* Private version of data source object */
typedef struct {
struct cjpeg_source_struct pub; /* public fields */
/* Usually these two pointers point to the same place: */
U_CHAR *iobuffer; /* fread's I/O buffer */
JSAMPROW pixrow; /* compressor input buffer */
size_t buffer_width; /* width of I/O buffer */
JSAMPLE *rescale; /* => maxval-remapping array, or NULL */
int maxval;
} ppm_source_struct;
typedef ppm_source_struct *ppm_source_ptr;
LOCAL(int)
pbm_getc (FILE *infile)
/* Read next char, skipping over any comments */
/* A comment/newline sequence is returned as a newline */
{
register int ch;
ch = getc(infile);
if (ch == '#') {
do {
ch = getc(infile);
} while (ch != '\n' && ch != EOF);
}
return ch;
}
LOCAL(unsigned int)
read_pbm_integer (j_compress_ptr cinfo, FILE *infile, unsigned int maxval)
/* Read an unsigned decimal integer from the PPM file */
/* Swallows one trailing character after the integer */
/* Note that on a 16-bit-int machine, only values up to 64k can be read. */
/* This should not be a problem in practice. */
{
register int ch;
register unsigned int val;
/* Skip any leading whitespace */
do {
ch = pbm_getc(infile);
if (ch == EOF)
ERREXIT(cinfo, JERR_INPUT_EOF);
} while (ch == ' ' || ch == '\t' || ch == '\n' || ch == '\r');
if (ch < '0' || ch > '9')
ERREXIT(cinfo, JERR_PPM_NONNUMERIC);
val = ch - '0';
while ((ch = pbm_getc(infile)) >= '0' && ch <= '9') {
val *= 10;
val += ch - '0';
}
if (val > maxval)
ERREXIT(cinfo, JERR_PPM_TOOLARGE);
return val;
}
/*
* Read one row of pixels.
*
* We provide several different versions depending on input file format.
* In all cases, input is scaled to the size of JSAMPLE.
*
* A really fast path is provided for reading byte/sample raw files with
* maxval = MAXJSAMPLE, which is the normal case for 8-bit data.
*/
METHODDEF(JDIMENSION)
get_text_gray_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading text-format PGM files with any maxval */
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
FILE *infile = source->pub.input_file;
register JSAMPROW ptr;
register JSAMPLE *rescale = source->rescale;
JDIMENSION col;
unsigned int maxval = source->maxval;
ptr = source->pub.buffer[0];
for (col = cinfo->image_width; col > 0; col--) {
*ptr++ = rescale[read_pbm_integer(cinfo, infile, maxval)];
}
return 1;
}
#define GRAY_RGB_READ_LOOP(read_op, alpha_set_op) { \
for (col = cinfo->image_width; col > 0; col--) { \
ptr[rindex] = ptr[gindex] = ptr[bindex] = read_op; \
alpha_set_op \
ptr += ps; \
} \
}
METHODDEF(JDIMENSION)
get_text_gray_rgb_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading text-format PGM files with any maxval and
converting to extended RGB */
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
FILE *infile = source->pub.input_file;
register JSAMPROW ptr;
register JSAMPLE *rescale = source->rescale;
JDIMENSION col;
unsigned int maxval = source->maxval;
register int rindex = rgb_red[cinfo->in_color_space];
register int gindex = rgb_green[cinfo->in_color_space];
register int bindex = rgb_blue[cinfo->in_color_space];
register int aindex = alpha_index[cinfo->in_color_space];
register int ps = rgb_pixelsize[cinfo->in_color_space];
ptr = source->pub.buffer[0];
if (maxval == MAXJSAMPLE) {
if (aindex >= 0)
GRAY_RGB_READ_LOOP(read_pbm_integer(cinfo, infile, maxval),
ptr[aindex] = 0xFF;)
else
GRAY_RGB_READ_LOOP(read_pbm_integer(cinfo, infile, maxval),)
} else {
if (aindex >= 0)
GRAY_RGB_READ_LOOP(rescale[read_pbm_integer(cinfo, infile, maxval)],
ptr[aindex] = 0xFF;)
else
GRAY_RGB_READ_LOOP(rescale[read_pbm_integer(cinfo, infile, maxval)],)
}
return 1;
}
METHODDEF(JDIMENSION)
get_text_gray_cmyk_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading text-format PGM files with any maxval and
converting to CMYK */
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
FILE *infile = source->pub.input_file;
register JSAMPROW ptr;
register JSAMPLE *rescale = source->rescale;
JDIMENSION col;
unsigned int maxval = source->maxval;
ptr = source->pub.buffer[0];
if (maxval == MAXJSAMPLE) {
for (col = cinfo->image_width; col > 0; col--) {
JSAMPLE gray = read_pbm_integer(cinfo, infile, maxval);
rgb_to_cmyk(gray, gray, gray, ptr, ptr + 1, ptr + 2, ptr + 3);
ptr += 4;
}
} else {
for (col = cinfo->image_width; col > 0; col--) {
JSAMPLE gray = rescale[read_pbm_integer(cinfo, infile, maxval)];
rgb_to_cmyk(gray, gray, gray, ptr, ptr + 1, ptr + 2, ptr + 3);
ptr += 4;
}
}
return 1;
}
#define RGB_READ_LOOP(read_op, alpha_set_op) { \
for (col = cinfo->image_width; col > 0; col--) { \
ptr[rindex] = read_op; \
ptr[gindex] = read_op; \
ptr[bindex] = read_op; \
alpha_set_op \
ptr += ps; \
} \
}
METHODDEF(JDIMENSION)
get_text_rgb_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading text-format PPM files with any maxval */
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
FILE *infile = source->pub.input_file;
register JSAMPROW ptr;
register JSAMPLE *rescale = source->rescale;
JDIMENSION col;
unsigned int maxval = source->maxval;
register int rindex = rgb_red[cinfo->in_color_space];
register int gindex = rgb_green[cinfo->in_color_space];
register int bindex = rgb_blue[cinfo->in_color_space];
register int aindex = alpha_index[cinfo->in_color_space];
register int ps = rgb_pixelsize[cinfo->in_color_space];
ptr = source->pub.buffer[0];
if (maxval == MAXJSAMPLE) {
if (aindex >= 0)
RGB_READ_LOOP(read_pbm_integer(cinfo, infile, maxval),
ptr[aindex] = 0xFF;)
else
RGB_READ_LOOP(read_pbm_integer(cinfo, infile, maxval),)
} else {
if (aindex >= 0)
RGB_READ_LOOP(rescale[read_pbm_integer(cinfo, infile, maxval)],
ptr[aindex] = 0xFF;)
else
RGB_READ_LOOP(rescale[read_pbm_integer(cinfo, infile, maxval)],)
}
return 1;
}
METHODDEF(JDIMENSION)
get_text_rgb_cmyk_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading text-format PPM files with any maxval and
converting to CMYK */
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
FILE *infile = source->pub.input_file;
register JSAMPROW ptr;
register JSAMPLE *rescale = source->rescale;
JDIMENSION col;
unsigned int maxval = source->maxval;
ptr = source->pub.buffer[0];
if (maxval == MAXJSAMPLE) {
for (col = cinfo->image_width; col > 0; col--) {
JSAMPLE r = read_pbm_integer(cinfo, infile, maxval);
JSAMPLE g = read_pbm_integer(cinfo, infile, maxval);
JSAMPLE b = read_pbm_integer(cinfo, infile, maxval);
rgb_to_cmyk(r, g, b, ptr, ptr + 1, ptr + 2, ptr + 3);
ptr += 4;
}
} else {
for (col = cinfo->image_width; col > 0; col--) {
JSAMPLE r = rescale[read_pbm_integer(cinfo, infile, maxval)];
JSAMPLE g = rescale[read_pbm_integer(cinfo, infile, maxval)];
JSAMPLE b = rescale[read_pbm_integer(cinfo, infile, maxval)];
rgb_to_cmyk(r, g, b, ptr, ptr + 1, ptr + 2, ptr + 3);
ptr += 4;
}
}
return 1;
}
METHODDEF(JDIMENSION)
get_scaled_gray_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading raw-byte-format PGM files with any maxval */
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
register JSAMPROW ptr;
register U_CHAR *bufferptr;
register JSAMPLE *rescale = source->rescale;
JDIMENSION col;
if (! ReadOK(source->pub.input_file, source->iobuffer, source->buffer_width))
ERREXIT(cinfo, JERR_INPUT_EOF);
ptr = source->pub.buffer[0];
bufferptr = source->iobuffer;
for (col = cinfo->image_width; col > 0; col--) {
*ptr++ = rescale[UCH(*bufferptr++)];
}
return 1;
}
METHODDEF(JDIMENSION)
get_gray_rgb_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading raw-byte-format PGM files with any maxval
and converting to extended RGB */
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
register JSAMPROW ptr;
register U_CHAR *bufferptr;
register JSAMPLE *rescale = source->rescale;
JDIMENSION col;
unsigned int maxval = source->maxval;
register int rindex = rgb_red[cinfo->in_color_space];
register int gindex = rgb_green[cinfo->in_color_space];
register int bindex = rgb_blue[cinfo->in_color_space];
register int aindex = alpha_index[cinfo->in_color_space];
register int ps = rgb_pixelsize[cinfo->in_color_space];
if (! ReadOK(source->pub.input_file, source->iobuffer, source->buffer_width))
ERREXIT(cinfo, JERR_INPUT_EOF);
ptr = source->pub.buffer[0];
bufferptr = source->iobuffer;
if (maxval == MAXJSAMPLE) {
if (aindex >= 0)
GRAY_RGB_READ_LOOP(*bufferptr++, ptr[aindex] = 0xFF;)
else
GRAY_RGB_READ_LOOP(*bufferptr++,)
} else {
if (aindex >= 0)
GRAY_RGB_READ_LOOP(rescale[UCH(*bufferptr++)], ptr[aindex] = 0xFF;)
else
GRAY_RGB_READ_LOOP(rescale[UCH(*bufferptr++)],)
}
return 1;
}
METHODDEF(JDIMENSION)
get_gray_cmyk_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading raw-byte-format PGM files with any maxval
and converting to CMYK */
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
register JSAMPROW ptr;
register U_CHAR *bufferptr;
register JSAMPLE *rescale = source->rescale;
JDIMENSION col;
unsigned int maxval = source->maxval;
if (! ReadOK(source->pub.input_file, source->iobuffer, source->buffer_width))
ERREXIT(cinfo, JERR_INPUT_EOF);
ptr = source->pub.buffer[0];
bufferptr = source->iobuffer;
if (maxval == MAXJSAMPLE) {
for (col = cinfo->image_width; col > 0; col--) {
JSAMPLE gray = *bufferptr++;
rgb_to_cmyk(gray, gray, gray, ptr, ptr + 1, ptr + 2, ptr + 3);
ptr += 4;
}
} else {
for (col = cinfo->image_width; col > 0; col--) {
JSAMPLE gray = rescale[UCH(*bufferptr++)];
rgb_to_cmyk(gray, gray, gray, ptr, ptr + 1, ptr + 2, ptr + 3);
ptr += 4;
}
}
return 1;
}
METHODDEF(JDIMENSION)
get_rgb_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading raw-byte-format PPM files with any maxval */
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
register JSAMPROW ptr;
register U_CHAR *bufferptr;
register JSAMPLE *rescale = source->rescale;
JDIMENSION col;
unsigned int maxval = source->maxval;
register int rindex = rgb_red[cinfo->in_color_space];
register int gindex = rgb_green[cinfo->in_color_space];
register int bindex = rgb_blue[cinfo->in_color_space];
register int aindex = alpha_index[cinfo->in_color_space];
register int ps = rgb_pixelsize[cinfo->in_color_space];
if (! ReadOK(source->pub.input_file, source->iobuffer, source->buffer_width))
ERREXIT(cinfo, JERR_INPUT_EOF);
ptr = source->pub.buffer[0];
bufferptr = source->iobuffer;
if (maxval == MAXJSAMPLE) {
if (aindex >= 0)
RGB_READ_LOOP(*bufferptr++, ptr[aindex] = 0xFF;)
else
RGB_READ_LOOP(*bufferptr++,)
} else {
if (aindex >= 0)
RGB_READ_LOOP(rescale[UCH(*bufferptr++)], ptr[aindex] = 0xFF;)
else
RGB_READ_LOOP(rescale[UCH(*bufferptr++)],)
}
return 1;
}
METHODDEF(JDIMENSION)
get_rgb_cmyk_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading raw-byte-format PPM files with any maxval and
converting to CMYK */
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
register JSAMPROW ptr;
register U_CHAR *bufferptr;
register JSAMPLE *rescale = source->rescale;
JDIMENSION col;
unsigned int maxval = source->maxval;
if (! ReadOK(source->pub.input_file, source->iobuffer, source->buffer_width))
ERREXIT(cinfo, JERR_INPUT_EOF);
ptr = source->pub.buffer[0];
bufferptr = source->iobuffer;
if (maxval == MAXJSAMPLE) {
for (col = cinfo->image_width; col > 0; col--) {
JSAMPLE r = *bufferptr++;
JSAMPLE g = *bufferptr++;
JSAMPLE b = *bufferptr++;
rgb_to_cmyk(r, g, b, ptr, ptr + 1, ptr + 2, ptr + 3);
ptr += 4;
}
} else {
for (col = cinfo->image_width; col > 0; col--) {
JSAMPLE r = rescale[UCH(*bufferptr++)];
JSAMPLE g = rescale[UCH(*bufferptr++)];
JSAMPLE b = rescale[UCH(*bufferptr++)];
rgb_to_cmyk(r, g, b, ptr, ptr + 1, ptr + 2, ptr + 3);
ptr += 4;
}
}
return 1;
}
METHODDEF(JDIMENSION)
get_raw_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading raw-byte-format files with maxval = MAXJSAMPLE.
* In this case we just read right into the JSAMPLE buffer!
* Note that same code works for PPM and PGM files.
*/
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
if (! ReadOK(source->pub.input_file, source->iobuffer, source->buffer_width))
ERREXIT(cinfo, JERR_INPUT_EOF);
return 1;
}
METHODDEF(JDIMENSION)
get_word_gray_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading raw-word-format PGM files with any maxval */
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
register JSAMPROW ptr;
register U_CHAR *bufferptr;
register JSAMPLE *rescale = source->rescale;
JDIMENSION col;
unsigned int maxval = source->maxval;
if (! ReadOK(source->pub.input_file, source->iobuffer, source->buffer_width))
ERREXIT(cinfo, JERR_INPUT_EOF);
ptr = source->pub.buffer[0];
bufferptr = source->iobuffer;
for (col = cinfo->image_width; col > 0; col--) {
register unsigned int temp;
temp = UCH(*bufferptr++) << 8;
temp |= UCH(*bufferptr++);
if (temp > maxval)
ERREXIT(cinfo, JERR_PPM_TOOLARGE);
*ptr++ = rescale[temp];
}
return 1;
}
METHODDEF(JDIMENSION)
get_word_rgb_row (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
/* This version is for reading raw-word-format PPM files with any maxval */
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
register JSAMPROW ptr;
register U_CHAR *bufferptr;
register JSAMPLE *rescale = source->rescale;
JDIMENSION col;
unsigned int maxval = source->maxval;
if (! ReadOK(source->pub.input_file, source->iobuffer, source->buffer_width))
ERREXIT(cinfo, JERR_INPUT_EOF);
ptr = source->pub.buffer[0];
bufferptr = source->iobuffer;
for (col = cinfo->image_width; col > 0; col--) {
register unsigned int temp;
temp = UCH(*bufferptr++) << 8;
temp |= UCH(*bufferptr++);
if (temp > maxval)
ERREXIT(cinfo, JERR_PPM_TOOLARGE);
*ptr++ = rescale[temp];
temp = UCH(*bufferptr++) << 8;
temp |= UCH(*bufferptr++);
if (temp > maxval)
ERREXIT(cinfo, JERR_PPM_TOOLARGE);
*ptr++ = rescale[temp];
temp = UCH(*bufferptr++) << 8;
temp |= UCH(*bufferptr++);
if (temp > maxval)
ERREXIT(cinfo, JERR_PPM_TOOLARGE);
*ptr++ = rescale[temp];
}
return 1;
}
/*
* Read the file header; return image size and component count.
*/
METHODDEF(void)
start_input_ppm (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
{
ppm_source_ptr source = (ppm_source_ptr) sinfo;
int c;
unsigned int w, h, maxval;
boolean need_iobuffer, use_raw_buffer, need_rescale;
if (getc(source->pub.input_file) != 'P')
ERREXIT(cinfo, JERR_PPM_NOT);
c = getc(source->pub.input_file); /* subformat discriminator character */
/* detect unsupported variants (ie, PBM) before trying to read header */
switch (c) {
case '2': /* it's a text-format PGM file */
case '3': /* it's a text-format PPM file */
case '5': /* it's a raw-format PGM file */
case '6': /* it's a raw-format PPM file */
break;
default:
ERREXIT(cinfo, JERR_PPM_NOT);
break;
}
/* fetch the remaining header info */
w = read_pbm_integer(cinfo, source->pub.input_file, 65535);
h = read_pbm_integer(cinfo, source->pub.input_file, 65535);
maxval = read_pbm_integer(cinfo, source->pub.input_file, 65535);
if (w <= 0 || h <= 0 || maxval <= 0) /* error check */
ERREXIT(cinfo, JERR_PPM_NOT);
cinfo->data_precision = BITS_IN_JSAMPLE; /* we always rescale data to this */
cinfo->image_width = (JDIMENSION) w;
cinfo->image_height = (JDIMENSION) h;
source->maxval = maxval;
/* initialize flags to most common settings */
need_iobuffer = TRUE; /* do we need an I/O buffer? */
use_raw_buffer = FALSE; /* do we map input buffer onto I/O buffer? */
need_rescale = TRUE; /* do we need a rescale array? */
switch (c) {
case '2': /* it's a text-format PGM file */
if (cinfo->in_color_space == JCS_UNKNOWN)
cinfo->in_color_space = JCS_GRAYSCALE;
TRACEMS2(cinfo, 1, JTRC_PGM_TEXT, w, h);
if (cinfo->in_color_space == JCS_GRAYSCALE)
source->pub.get_pixel_rows = get_text_gray_row;
else if (IsExtRGB(cinfo->in_color_space))
source->pub.get_pixel_rows = get_text_gray_rgb_row;
else if (cinfo->in_color_space == JCS_CMYK)
source->pub.get_pixel_rows = get_text_gray_cmyk_row;
else
ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
need_iobuffer = FALSE;
break;
case '3': /* it's a text-format PPM file */
if (cinfo->in_color_space == JCS_UNKNOWN)
cinfo->in_color_space = JCS_EXT_RGB;
TRACEMS2(cinfo, 1, JTRC_PPM_TEXT, w, h);
if (IsExtRGB(cinfo->in_color_space))
source->pub.get_pixel_rows = get_text_rgb_row;
else if (cinfo->in_color_space == JCS_CMYK)
source->pub.get_pixel_rows = get_text_rgb_cmyk_row;
else
ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
need_iobuffer = FALSE;
break;
case '5': /* it's a raw-format PGM file */
if (cinfo->in_color_space == JCS_UNKNOWN)
cinfo->in_color_space = JCS_GRAYSCALE;
TRACEMS2(cinfo, 1, JTRC_PGM, w, h);
if (maxval > 255) {
source->pub.get_pixel_rows = get_word_gray_row;
} else if (maxval == MAXJSAMPLE && sizeof(JSAMPLE) == sizeof(U_CHAR) &&
cinfo->in_color_space == JCS_GRAYSCALE) {
source->pub.get_pixel_rows = get_raw_row;
use_raw_buffer = TRUE;
need_rescale = FALSE;
} else {
if (cinfo->in_color_space == JCS_GRAYSCALE)
source->pub.get_pixel_rows = get_scaled_gray_row;
else if (IsExtRGB(cinfo->in_color_space))
source->pub.get_pixel_rows = get_gray_rgb_row;
else if (cinfo->in_color_space == JCS_CMYK)
source->pub.get_pixel_rows = get_gray_cmyk_row;
else
ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
}
break;
case '6': /* it's a raw-format PPM file */
if (cinfo->in_color_space == JCS_UNKNOWN)
cinfo->in_color_space = JCS_EXT_RGB;
TRACEMS2(cinfo, 1, JTRC_PPM, w, h);
if (maxval > 255) {
source->pub.get_pixel_rows = get_word_rgb_row;
} else if (maxval == MAXJSAMPLE && sizeof(JSAMPLE) == sizeof(U_CHAR) &&
(cinfo->in_color_space == JCS_EXT_RGB
#if RGB_RED == 0 && RGB_GREEN == 1 && RGB_BLUE == 2 && RGB_PIXELSIZE == 3
|| cinfo->in_color_space == JCS_RGB)) {
#endif
source->pub.get_pixel_rows = get_raw_row;
use_raw_buffer = TRUE;
need_rescale = FALSE;
} else {
if (IsExtRGB(cinfo->in_color_space))
source->pub.get_pixel_rows = get_rgb_row;
else if (cinfo->in_color_space == JCS_CMYK)
source->pub.get_pixel_rows = get_rgb_cmyk_row;
else
ERREXIT(cinfo, JERR_BAD_IN_COLORSPACE);
}
break;
}
if (IsExtRGB(cinfo->in_color_space))
cinfo->input_components = rgb_pixelsize[cinfo->in_color_space];
else if (cinfo->in_color_space == JCS_GRAYSCALE)
cinfo->input_components = 1;
else if (cinfo->in_color_space == JCS_CMYK)
cinfo->input_components = 4;
/* Allocate space for I/O buffer: 1 or 3 bytes or words/pixel. */
if (need_iobuffer) {
if (c == '6')
source->buffer_width = (size_t) w * 3 *
((maxval <= 255) ? sizeof(U_CHAR) : (2 * sizeof(U_CHAR)));
else
source->buffer_width = (size_t) w *
((maxval <= 255) ? sizeof(U_CHAR) : (2 * sizeof(U_CHAR)));
source->iobuffer = (U_CHAR *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
source->buffer_width);
}
/* Create compressor input buffer. */
if (use_raw_buffer) {
/* For unscaled raw-input case, we can just map it onto the I/O buffer. */
/* Synthesize a JSAMPARRAY pointer structure */
source->pixrow = (JSAMPROW) source->iobuffer;
source->pub.buffer = & source->pixrow;
source->pub.buffer_height = 1;
} else {
/* Need to translate anyway, so make a separate sample buffer. */
source->pub.buffer = (*cinfo->mem->alloc_sarray)
((j_common_ptr) cinfo, JPOOL_IMAGE,
(JDIMENSION) w * cinfo->input_components, (JDIMENSION) 1);
source->pub.buffer_height = 1;
}
/* Compute the rescaling array if required. */
if (need_rescale) {
long val, half_maxval;
/* On 16-bit-int machines we have to be careful of maxval = 65535 */
source->rescale = (JSAMPLE *)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
(size_t) (((long) maxval + 1L) *
sizeof(JSAMPLE)));
half_maxval = maxval / 2;
for (val = 0; val <= (long) maxval; val++) {
/* The multiplication here must be done in 32 bits to avoid overflow */
source->rescale[val] = (JSAMPLE) ((val * MAXJSAMPLE + half_maxval) /
maxval);
}
}
}
/*
* Finish up at the end of the file.
*/
METHODDEF(void)
finish_input_ppm (j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
{
/* no work */
}
/*
* The module selection routine for PPM format input.
*/
GLOBAL(cjpeg_source_ptr)
jinit_read_ppm (j_compress_ptr cinfo)
{
ppm_source_ptr source;
/* Create module interface object */
source = (ppm_source_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
sizeof(ppm_source_struct));
/* Fill in method ptrs, except get_pixel_rows which start_input sets */
source->pub.start_input = start_input_ppm;
source->pub.finish_input = finish_input_ppm;
return (cjpeg_source_ptr) source;
}
#endif /* PPM_SUPPORTED */