wrppm.c - third_party/libjpeg-turbo - Git at Google

 /*
  * 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.
  * It was modified by The libjpeg-turbo Project to include only code and
  * information relevant to libjpeg-turbo.
  * 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 "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)  *ptr++ = (char) (v)
 #define BYTESPERSAMPLE 1
 #define PPM_MAXVAL 255
 #else
 #ifdef PPM_NORAWWORD
 #define PUTPPMSAMPLE(ptr,v)  *ptr++ = (char) ((v) >> (BITS_IN_JSAMPLE-8))
 #define BYTESPERSAMPLE 1
 #define PPM_MAXVAL 255
 #else
 /* The word-per-sample format always puts the MSB first. */
 #define PUTPPMSAMPLE(ptr,v)                     \
         { register int val_ = v;                \
           *ptr++ = (char) ((val_ >> 8) & 0xFF); \
           *ptr++ = (char) (val_ & 0xFF);        \
         }
 #define BYTESPERSAMPLE 2
 #define PPM_MAXVAL ((1<<BITS_IN_JSAMPLE)-1)
 #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 */

 typedef struct {
   struct djpeg_dest_struct pub; /* public fields */

   /* Usually these two pointers point to the same place: */
   char *iobuffer;               /* fwrite's I/O buffer */
   JSAMPROW pixrow;              /* decompressor output buffer */
   size_t buffer_width;          /* width of I/O buffer */
   JDIMENSION samples_per_row;   /* JSAMPLEs per output row */
 } ppm_dest_struct;

 typedef 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)
 {
   ppm_dest_ptr dest = (ppm_dest_ptr) dinfo;

   (void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
 }


 /*
  * 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)
 {
   ppm_dest_ptr dest = (ppm_dest_ptr) dinfo;
   register char * bufferptr;
   register JSAMPROW ptr;
   register JDIMENSION col;

   ptr = dest->pub.buffer[0];
   bufferptr = dest->iobuffer;
   for (col = dest->samples_per_row; col > 0; col--) {
     PUTPPMSAMPLE(bufferptr, GETJSAMPLE(*ptr++));
   }
   (void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
 }


 /*
  * 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)
 {
   ppm_dest_ptr dest = (ppm_dest_ptr) dinfo;
   register char * bufferptr;
   register int pixval;
   register JSAMPROW ptr;
   register JSAMPROW color_map0 = cinfo->colormap[0];
   register JSAMPROW color_map1 = cinfo->colormap[1];
   register JSAMPROW color_map2 = cinfo->colormap[2];
   register JDIMENSION col;

   ptr = dest->pub.buffer[0];
   bufferptr = dest->iobuffer;
   for (col = cinfo->output_width; col > 0; col--) {
     pixval = GETJSAMPLE(*ptr++);
     PUTPPMSAMPLE(bufferptr, GETJSAMPLE(color_map0[pixval]));
     PUTPPMSAMPLE(bufferptr, GETJSAMPLE(color_map1[pixval]));
     PUTPPMSAMPLE(bufferptr, GETJSAMPLE(color_map2[pixval]));
   }
   (void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
 }


 METHODDEF(void)
 put_demapped_gray (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
                    JDIMENSION rows_supplied)
 {
   ppm_dest_ptr dest = (ppm_dest_ptr) dinfo;
   register char * bufferptr;
   register JSAMPROW ptr;
   register JSAMPROW color_map = cinfo->colormap[0];
   register JDIMENSION col;

   ptr = dest->pub.buffer[0];
   bufferptr = dest->iobuffer;
   for (col = cinfo->output_width; col > 0; col--) {
     PUTPPMSAMPLE(bufferptr, GETJSAMPLE(color_map[GETJSAMPLE(*ptr++)]));
   }
   (void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
 }


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

 METHODDEF(void)
 start_output_ppm (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
 {
   ppm_dest_ptr dest = (ppm_dest_ptr) dinfo;

   /* Emit file header */
   switch (cinfo->out_color_space) {
   case JCS_GRAYSCALE:
     /* emit header for raw PGM format */
     fprintf(dest->pub.output_file, "P5\n%ld %ld\n%d\n",
             (long) cinfo->output_width, (long) cinfo->output_height,
             PPM_MAXVAL);
     break;
   case JCS_RGB:
     /* emit header for raw PPM format */
     fprintf(dest->pub.output_file, "P6\n%ld %ld\n%d\n",
             (long) cinfo->output_width, (long) cinfo->output_height,
             PPM_MAXVAL);
     break;
   default:
     ERREXIT(cinfo, JERR_PPM_COLORSPACE);
   }
 }


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

 METHODDEF(void)
 finish_output_ppm (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
 {
   /* Make sure we wrote the output file OK */
   fflush(dinfo->output_file);
   if (ferror(dinfo->output_file))
     ERREXIT(cinfo, JERR_FILE_WRITE);
 }


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

 GLOBAL(djpeg_dest_ptr)
 jinit_write_ppm (j_decompress_ptr cinfo)
 {
   ppm_dest_ptr dest;

   /* Create module interface object, fill in method pointers */
   dest = (ppm_dest_ptr)
       (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                                   sizeof(ppm_dest_struct));
   dest->pub.start_output = start_output_ppm;
   dest->pub.finish_output = finish_output_ppm;

   /* Calculate output image dimensions so we can allocate space */
   jpeg_calc_output_dimensions(cinfo);

   /* Create physical I/O buffer */
   dest->samples_per_row = cinfo->output_width * cinfo->out_color_components;
   dest->buffer_width = dest->samples_per_row * (BYTESPERSAMPLE * sizeof(char));
   dest->iobuffer = (char *) (*cinfo->mem->alloc_small)
     ((j_common_ptr) cinfo, JPOOL_IMAGE, dest->buffer_width);

   if (cinfo->quantize_colors || BITS_IN_JSAMPLE != 8 ||
       sizeof(JSAMPLE) != sizeof(char)) {
     /* When quantizing, we need an output buffer for colormap indexes
      * that's separate from the physical I/O buffer.  We also need a
      * separate buffer if pixel format translation must take place.
      */
     dest->pub.buffer = (*cinfo->mem->alloc_sarray)
       ((j_common_ptr) cinfo, JPOOL_IMAGE,
        cinfo->output_width * cinfo->output_components, (JDIMENSION) 1);
     dest->pub.buffer_height = 1;
     if (! cinfo->quantize_colors)
       dest->pub.put_pixel_rows = copy_pixel_rows;
     else if (cinfo->out_color_space == JCS_GRAYSCALE)
       dest->pub.put_pixel_rows = put_demapped_gray;
     else
       dest->pub.put_pixel_rows = put_demapped_rgb;
   } else {
     /* We will fwrite() directly from decompressor output buffer. */
     /* Synthesize a JSAMPARRAY pointer structure */
     dest->pixrow = (JSAMPROW) dest->iobuffer;
     dest->pub.buffer = & dest->pixrow;
     dest->pub.buffer_height = 1;
     dest->pub.put_pixel_rows = put_pixel_rows;
   }

   return (djpeg_dest_ptr) dest;
 }

 #endif /* PPM_SUPPORTED */
	/*
	* 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.
	* It was modified by The libjpeg-turbo Project to include only code and
	* information relevant to libjpeg-turbo.
	* 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 "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) *ptr++ = (char) (v)
	#define BYTESPERSAMPLE 1
	#define PPM_MAXVAL 255
	#else
	#ifdef PPM_NORAWWORD
	#define PUTPPMSAMPLE(ptr,v) *ptr++ = (char) ((v) >> (BITS_IN_JSAMPLE-8))
	#define BYTESPERSAMPLE 1
	#define PPM_MAXVAL 255
	#else
	/* The word-per-sample format always puts the MSB first. */
	#define PUTPPMSAMPLE(ptr,v) \
	{ register int val_ = v; \
	*ptr++ = (char) ((val_ >> 8) & 0xFF); \
	*ptr++ = (char) (val_ & 0xFF); \
	}
	#define BYTESPERSAMPLE 2
	#define PPM_MAXVAL ((1<<BITS_IN_JSAMPLE)-1)
	#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 */

	typedef struct {
	struct djpeg_dest_struct pub; /* public fields */

	/* Usually these two pointers point to the same place: */
	char iobuffer; / fwrite's I/O buffer */
	JSAMPROW pixrow; /* decompressor output buffer */
	size_t buffer_width; /* width of I/O buffer */
	JDIMENSION samples_per_row; /* JSAMPLEs per output row */
	} ppm_dest_struct;

	typedef 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)
	{
	ppm_dest_ptr dest = (ppm_dest_ptr) dinfo;

	(void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
	}


	/*
	* 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)
	{
	ppm_dest_ptr dest = (ppm_dest_ptr) dinfo;
	register char * bufferptr;
	register JSAMPROW ptr;
	register JDIMENSION col;

	ptr = dest->pub.buffer[0];
	bufferptr = dest->iobuffer;
	for (col = dest->samples_per_row; col > 0; col--) {
	PUTPPMSAMPLE(bufferptr, GETJSAMPLE(*ptr++));
	}
	(void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
	}


	/*
	* 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)
	{
	ppm_dest_ptr dest = (ppm_dest_ptr) dinfo;
	register char * bufferptr;
	register int pixval;
	register JSAMPROW ptr;
	register JSAMPROW color_map0 = cinfo->colormap[0];
	register JSAMPROW color_map1 = cinfo->colormap[1];
	register JSAMPROW color_map2 = cinfo->colormap[2];
	register JDIMENSION col;

	ptr = dest->pub.buffer[0];
	bufferptr = dest->iobuffer;
	for (col = cinfo->output_width; col > 0; col--) {
	pixval = GETJSAMPLE(*ptr++);
	PUTPPMSAMPLE(bufferptr, GETJSAMPLE(color_map0[pixval]));
	PUTPPMSAMPLE(bufferptr, GETJSAMPLE(color_map1[pixval]));
	PUTPPMSAMPLE(bufferptr, GETJSAMPLE(color_map2[pixval]));
	}
	(void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
	}


	METHODDEF(void)
	put_demapped_gray (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
	JDIMENSION rows_supplied)
	{
	ppm_dest_ptr dest = (ppm_dest_ptr) dinfo;
	register char * bufferptr;
	register JSAMPROW ptr;
	register JSAMPROW color_map = cinfo->colormap[0];
	register JDIMENSION col;

	ptr = dest->pub.buffer[0];
	bufferptr = dest->iobuffer;
	for (col = cinfo->output_width; col > 0; col--) {
	PUTPPMSAMPLE(bufferptr, GETJSAMPLE(color_map[GETJSAMPLE(*ptr++)]));
	}
	(void) JFWRITE(dest->pub.output_file, dest->iobuffer, dest->buffer_width);
	}


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

	METHODDEF(void)
	start_output_ppm (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
	{
	ppm_dest_ptr dest = (ppm_dest_ptr) dinfo;

	/* Emit file header */
	switch (cinfo->out_color_space) {
	case JCS_GRAYSCALE:
	/* emit header for raw PGM format */
	fprintf(dest->pub.output_file, "P5\n%ld %ld\n%d\n",
	(long) cinfo->output_width, (long) cinfo->output_height,
	PPM_MAXVAL);
	break;
	case JCS_RGB:
	/* emit header for raw PPM format */
	fprintf(dest->pub.output_file, "P6\n%ld %ld\n%d\n",
	(long) cinfo->output_width, (long) cinfo->output_height,
	PPM_MAXVAL);
	break;
	default:
	ERREXIT(cinfo, JERR_PPM_COLORSPACE);
	}
	}


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

	METHODDEF(void)
	finish_output_ppm (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
	{
	/* Make sure we wrote the output file OK */
	fflush(dinfo->output_file);
	if (ferror(dinfo->output_file))
	ERREXIT(cinfo, JERR_FILE_WRITE);
	}


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

	GLOBAL(djpeg_dest_ptr)
	jinit_write_ppm (j_decompress_ptr cinfo)
	{
	ppm_dest_ptr dest;

	/* Create module interface object, fill in method pointers */
	dest = (ppm_dest_ptr)
	(*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
	sizeof(ppm_dest_struct));
	dest->pub.start_output = start_output_ppm;
	dest->pub.finish_output = finish_output_ppm;

	/* Calculate output image dimensions so we can allocate space */
	jpeg_calc_output_dimensions(cinfo);

	/* Create physical I/O buffer */
	dest->samples_per_row = cinfo->output_width * cinfo->out_color_components;
	dest->buffer_width = dest->samples_per_row * (BYTESPERSAMPLE * sizeof(char));
	dest->iobuffer = (char ) (cinfo->mem->alloc_small)
	((j_common_ptr) cinfo, JPOOL_IMAGE, dest->buffer_width);

	if (cinfo->quantize_colors \|\| BITS_IN_JSAMPLE != 8 \|\|
	sizeof(JSAMPLE) != sizeof(char)) {
	/* When quantizing, we need an output buffer for colormap indexes
	* that's separate from the physical I/O buffer. We also need a
	* separate buffer if pixel format translation must take place.
	*/
	dest->pub.buffer = (*cinfo->mem->alloc_sarray)
	((j_common_ptr) cinfo, JPOOL_IMAGE,
	cinfo->output_width * cinfo->output_components, (JDIMENSION) 1);
	dest->pub.buffer_height = 1;
	if (! cinfo->quantize_colors)
	dest->pub.put_pixel_rows = copy_pixel_rows;
	else if (cinfo->out_color_space == JCS_GRAYSCALE)
	dest->pub.put_pixel_rows = put_demapped_gray;
	else
	dest->pub.put_pixel_rows = put_demapped_rgb;
	} else {
	/* We will fwrite() directly from decompressor output buffer. */
	/* Synthesize a JSAMPARRAY pointer structure */
	dest->pixrow = (JSAMPROW) dest->iobuffer;
	dest->pub.buffer = & dest->pixrow;
	dest->pub.buffer_height = 1;
	dest->pub.put_pixel_rows = put_pixel_rows;
	}

	return (djpeg_dest_ptr) dest;
	}

	#endif /* PPM_SUPPORTED */