/* * wrraw.c * * Copyright (C) 1991-1994, 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 the raw YCC subsampled data * read from the jpeg file. * * These routines may need modification for non-Unix environments or * specialized applications.  As they stand, they assume output to * an ordinary stdio stream. *   *  Based on code contributed by James Arthur Boucher */#include "cdjpeg.h"             /* Common decls for cjpeg/djpeg applications */#ifdef RAW_SUPPORTED/* * Haven't yet got around to making this work with text-format output, * hence cannot handle pixels wider than 8 bits. */#if BITS_IN_JSAMPLE != 8  Sorry, this code only copes with 8-bit JSAMPLEs. /* deliberate syntax err */#endif/* * * The output buffer needs to be writable by fwrite().  On PCs, we must * allocate the buffer in near data space, because we are assuming small-data * memory model, wherein fwrite() can't reach far memory.  If you need to * process very wide images on a PC, you might have to compile in large-memory * model, or else replace fwrite() with a putc() loop --- which will be much * slower. *//* Private version of data destination object */typedef struct {  struct djpeg_dest_struct pub; /* public fields */  JSAMPLE *iobuffer;            /* non-FAR pointer to I/O buffer */  JSAMPROW pixrow;              /* FAR pointer to same */  JDIMENSION buffer_width;      /* width of one row */} raw_dest_struct;typedef raw_dest_struct * raw_dest_ptr;/* * Write some pixel data. In this module rows_supplied can be variable */METHODDEF voidput_pixel_rows (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,		JDIMENSION rows_supplied){  raw_dest_ptr dest = (raw_dest_ptr) dinfo;  int ci,cp;  JDIMENSION ncols,nrows;  jpeg_component_info *compptr;  TRACEMS(cinfo,2,JERR_RAW_PPR);  for(cp=0,compptr = cinfo->comp_info; cp <cinfo->num_components;       cp++,compptr++){   ncols = (JDIMENSION)((cinfo->image_width*compptr->h_samp_factor)/           cinfo->max_h_samp_factor);   nrows = (JDIMENSION)((rows_supplied*compptr->v_samp_factor)/           cinfo->max_v_samp_factor);  for(ci =0;ci<nrows;ci++){  TRACEMS1(cinfo,3,JTRC_RAW_PUTROW,ci);  (void) JFWRITE(dest->pub.output_file, dest->pub.image_buffer[cp][ci],               ncols);   }}   TRACEMS(cinfo,2,JTRC_RAW_PUTEND);  }/* * Startup: write null header. */METHODDEF voidstart_output (j_decompress_ptr cinfo, djpeg_dest_ptr dinfo){ /* do nothing*/}/* * Finish up at the end of the file. */METHODDEF voidfinish_output (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 raw format output. */GLOBAL djpeg_dest_ptrjinit_write_raw (j_decompress_ptr cinfo){  raw_dest_ptr dest;  int cp;  JDIMENSION ncols,nrows;  jpeg_component_info *compptr;  int temp;  int h_samp[3],v_samp[3];  TRACEMS(cinfo,1,JTRC_RAW_INIT);  cinfo->out_color_space = JCS_YCbCr; /* We want YCbCr or YUV output */  cinfo->want_raw_output = TRUE;     /* boolean used in main and api */  /* This module does not work unless JSAMPLE is a char. */  /* Unfortunately, we can't test it at compile time. */  if (SIZEOF(JSAMPLE) != SIZEOF(char))    ERREXIT(cinfo, JERR_RAW_SAMPLESIZE);  /* Create module interface object, fill in method pointers */  dest = (raw_dest_ptr)      (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,				  SIZEOF(raw_dest_struct));  dest->pub.start_output = start_output;  dest->pub.finish_output = finish_output;  /* Calculate output image dimensions so we can allocate space */  jpeg_calc_output_dimensions(cinfo);  /* Create I/O buffer.  Note we make this near on a PC. */  dest->buffer_width = (cinfo->output_width);/* calculate max_h(v)_samp_factors since not done yet */  for(cp=0,compptr = cinfo->comp_info;cp<cinfo->num_components;          cp++,compptr++){   h_samp[cp] = compptr->h_samp_factor;   v_samp[cp] = compptr->v_samp_factor; }  /* assumes three components */  temp = (h_samp[0]<h_samp[1]) ? h_samp[1] : h_samp[0];  cinfo->max_h_samp_factor = (temp<h_samp[2]) ? h_samp[2]:temp;  temp = (v_samp[0]<v_samp[1]) ? v_samp[1]:v_samp[0];  cinfo->max_v_samp_factor = (temp<v_samp[2]) ? v_samp[2]:temp;  /* chose to make buffer up to 8 rows high, 2 and 4 also valid */  dest->pub.buffer_height = 8;/* allocate sample arrays for each component */  for(cp=0,compptr = cinfo->comp_info;cp<cinfo->num_components;            cp++,compptr++){    ncols = (JDIMENSION)((cinfo->image_width*compptr->h_samp_factor)/          cinfo->max_h_samp_factor);    nrows = (JDIMENSION)((dest->pub.buffer_height*compptr->v_samp_factor)/            cinfo->max_v_samp_factor);    dest->pub.image_buffer[cp] = (*cinfo->mem->alloc_sarray)((j_common_ptr)                      cinfo,JPOOL_IMAGE,ncols,nrows);   }    dest->pub.put_pixel_rows = put_pixel_rows;    TRACEMS(cinfo,1,JTRC_RAW_IEND);  return (djpeg_dest_ptr) dest;}#endif /* RAW_SUPPORTED */