wrppm.c | Explore in Territory

/*
 * wrppm.c
 *
 * This file was part of the Independent JPEG Group's software:
 * Copyright (C) 1991-1996, Thomas G. Lane.
 * Modified 2009 by Guido Vollbeding.
 * libjpeg-turbo Modifications:
 * Copyright (C) 2017, 2019-2020, 2022, D. R. Commander.
 * For conditions of distribution and use, see the accompanying README.ijg
 * file.
 *
 * This file contains routines to write output 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 output to
 * an ordinary stdio stream.
 */

#include "cmyk.h"
#include "cdjpeg.h"             /* Common decls for cjpeg/djpeg applications */

#ifdef PPM_SUPPORTED


/*
 * For 12-bit JPEG data, we either downscale the values to 8 bits
 * (to write standard byte-per-sample PPM/PGM files), or output
 * nonstandard word-per-sample PPM/PGM files.  Downscaling is done
 * if PPM_NORAWWORD is defined (this can be done in the Makefile
 * or in jconfig.h).
 * (When the core library supports data precision reduction, a cleaner
 * implementation will be to ask for that instead.)
 */

#if BITS_IN_JSAMPLE == 8
#define PUTPPMSAMPLE(ptr, v) …
#define BYTESPERSAMPLE …
#define PPM_MAXVAL …
#else
#ifdef PPM_NORAWWORD
#define PUTPPMSAMPLE …
#define BYTESPERSAMPLE …
#define PPM_MAXVAL …
#else
/* The word-per-sample format always puts the MSB first. */
#define PUTPPMSAMPLE …
#define BYTESPERSAMPLE …
#define PPM_MAXVAL …
#endif
#endif


/*
 * When JSAMPLE is the same size as char, we can just fwrite() the
 * decompressed data to the PPM or PGM file.
 */


/* Private version of data destination object */

ppm_dest_struct;

ppm_dest_ptr;


/*
 * Write some pixel data.
 * In this module rows_supplied will always be 1.
 *
 * put_pixel_rows handles the "normal" 8-bit case where the decompressor
 * output buffer is physically the same as the fwrite buffer.
 */

METHODDEF(void)
put_pixel_rows(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
               JDIMENSION rows_supplied)
{ … }


/*
 * This code is used when we have to copy the data and apply a pixel
 * format translation.  Typically this only happens in 12-bit mode.
 */

METHODDEF(void)
copy_pixel_rows(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
                JDIMENSION rows_supplied)
{ … }


/*
 * Convert extended RGB to RGB.
 */

METHODDEF(void)
put_rgb(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo, JDIMENSION rows_supplied)
{ … }


/*
 * Convert CMYK to RGB.
 */

METHODDEF(void)
put_cmyk(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
         JDIMENSION rows_supplied)
{ … }


/*
 * Write some pixel data when color quantization is in effect.
 * We have to demap the color index values to straight data.
 */

METHODDEF(void)
put_demapped_rgb(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
                 JDIMENSION rows_supplied)
{ … }


METHODDEF(void)
put_demapped_gray(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
                  JDIMENSION rows_supplied)
{ … }


/*
 * Startup: write the file header.
 */

METHODDEF(void)
start_output_ppm(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
{ … }


/*
 * Finish up at the end of the file.
 */

METHODDEF(void)
finish_output_ppm(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
{ … }


/*
 * Re-calculate buffer dimensions based on output dimensions.
 */

METHODDEF(void)
calc_buffer_dimensions_ppm(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
{ … }


/*
 * The module selection routine for PPM format output.
 */

GLOBAL(djpeg_dest_ptr)
jinit_write_ppm(j_decompress_ptr cinfo)
{ … }

#endif /* PPM_SUPPORTED */
chromium/third_party/libjpeg_turbo/wrppm.c
