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/*
* jwrppm.c
*
* Copyright (C) 1991, 1992, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains routines to write output images in PPM format.
* The PBMPLUS library is required (well, it will be in the real version).
*
* These routines may need modification for non-Unix environments or
* specialized applications. As they stand, they assume output to
* an ordinary stdio stream.
*
* These routines are invoked via the methods put_pixel_rows, put_color_map,
* and output_init/term.
*/
#include "jinclude.h"
#ifdef PPM_SUPPORTED
/*
* Haven't yet got around to making this work with text-format output,
* hence cannot handle pixels wider than 8 bits.
*/
#ifndef EIGHT_BIT_SAMPLES
Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */
#endif
/*
* Write the file header.
*/
METHODDEF void
output_init (decompress_info_ptr cinfo)
{
if (cinfo->out_color_space == CS_GRAYSCALE) {
/* emit header for raw PGM format */
fprintf(cinfo->output_file, "P5\n%ld %ld\n%d\n",
cinfo->image_width, cinfo->image_height, 255);
} else if (cinfo->out_color_space == CS_RGB) {
/* emit header for raw PPM format */
fprintf(cinfo->output_file, "P6\n%ld %ld\n%d\n",
cinfo->image_width, cinfo->image_height, 255);
} else {
ERREXIT(cinfo->emethods, "PPM output must be grayscale or RGB");
}
}
/*
* Write some pixel data.
*/
METHODDEF void
put_pixel_rows (decompress_info_ptr cinfo, int num_rows,
JSAMPIMAGE pixel_data)
{
register FILE * outfile = cinfo->output_file;
register JSAMPROW ptr0, ptr1, ptr2;
register long col;
register long width = cinfo->image_width;
register int row;
if (cinfo->out_color_space == CS_GRAYSCALE) {
for (row = 0; row < num_rows; row++) {
ptr0 = pixel_data[0][row];
for (col = width; col > 0; col--) {
putc(GETJSAMPLE(*ptr0), outfile);
ptr0++;
}
}
} else {
for (row = 0; row < num_rows; row++) {
ptr0 = pixel_data[0][row];
ptr1 = pixel_data[1][row];
ptr2 = pixel_data[2][row];
for (col = width; col > 0; col--) {
putc(GETJSAMPLE(*ptr0), outfile);
ptr0++;
putc(GETJSAMPLE(*ptr1), outfile);
ptr1++;
putc(GETJSAMPLE(*ptr2), outfile);
ptr2++;
}
}
}
}
/*
* Write some pixel data when color quantization is in effect.
*/
METHODDEF void
put_demapped_rows (decompress_info_ptr cinfo, int num_rows,
JSAMPIMAGE pixel_data)
{
register FILE * outfile = cinfo->output_file;
register JSAMPARRAY color_map = cinfo->colormap;
register JSAMPROW ptr;
register long col;
long width = cinfo->image_width;
int row;
if (cinfo->out_color_space == CS_GRAYSCALE) {
for (row = 0; row < num_rows; row++) {
ptr = pixel_data[0][row];
for (col = width; col > 0; col--) {
putc(GETJSAMPLE(color_map[0][GETJSAMPLE(*ptr)]), outfile);
ptr++;
}
}
} else {
for (row = 0; row < num_rows; row++) {
ptr = pixel_data[0][row];
for (col = width; col > 0; col--) {
register int pixval = GETJSAMPLE(*ptr);
putc(GETJSAMPLE(color_map[0][pixval]), outfile);
putc(GETJSAMPLE(color_map[1][pixval]), outfile);
putc(GETJSAMPLE(color_map[2][pixval]), outfile);
ptr++;
}
}
}
}
/*
* Write the color map.
* For PPM output, we just demap the output data!
*/
METHODDEF void
put_color_map (decompress_info_ptr cinfo, int num_colors, JSAMPARRAY colormap)
{
cinfo->methods->put_pixel_rows = put_demapped_rows;
}
/*
* Finish up at the end of the file.
*/
METHODDEF void
output_term (decompress_info_ptr cinfo)
{
/* No work except to make sure we wrote the output file OK */
fflush(cinfo->output_file);
if (ferror(cinfo->output_file))
ERREXIT(cinfo->emethods, "Output file write error");
}
/*
* The method selection routine for PPM format output.
* This should be called from d_ui_method_selection if PPM output is wanted.
*/
GLOBAL void
jselwppm (decompress_info_ptr cinfo)
{
cinfo->methods->output_init = output_init;
cinfo->methods->put_color_map = put_color_map;
cinfo->methods->put_pixel_rows = put_pixel_rows;
cinfo->methods->output_term = output_term;
}
#endif /* PPM_SUPPORTED */
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.