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/*
 * jcapimin.c
 *
 * Copyright (C) 1994-1998, Thomas G. Lane.
 * Modified 2003-2010 by Guido Vollbeding.
 * 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 application interface code for the compression half
 * of the JPEG library.  These are the "minimum" API routines that may be
 * needed in either the normal full-compression case or the transcoding-only
 * case.
 *
 * Most of the routines intended to be called directly by an application
 * are in this file or in jcapistd.c.  But also see jcparam.c for
 * parameter-setup helper routines, jcomapi.c for routines shared by
 * compression and decompression, and jctrans.c for the transcoding case.
 */

#define JPEG_INTERNALS
#include "jinclude.h"
#include "jpeglib.h"


/*
 * Initialization of a JPEG compression object.
 * The error manager must already be set up (in case memory manager fails).
 */

GLOBAL(void)
jpeg_CreateCompress (j_compress_ptr cinfo, int version, size_t structsize)
{
  int i;

  /* Guard against version mismatches between library and caller. */
  cinfo->mem = NULL;		/* so jpeg_destroy knows mem mgr not called */
  if (version != JPEG_LIB_VERSION)
    ERREXIT2(cinfo, JERR_BAD_LIB_VERSION, JPEG_LIB_VERSION, version);
  if (structsize != SIZEOF(struct jpeg_compress_struct))
    ERREXIT2(cinfo, JERR_BAD_STRUCT_SIZE, 
	     (int) SIZEOF(struct jpeg_compress_struct), (int) structsize);

  /* For debugging purposes, we zero the whole master structure.
   * But the application has already set the err pointer, and may have set
   * client_data, so we have to save and restore those fields.
   * Note: if application hasn't set client_data, tools like Purify may
   * complain here.
   */
  {
    struct jpeg_error_mgr * err = cinfo->err;
    void * client_data = cinfo->client_data; /* ignore Purify complaint here */
    MEMZERO(cinfo, SIZEOF(struct jpeg_compress_struct));
    cinfo->err = err;
    cinfo->client_data = client_data;
  }
  cinfo->is_decompressor = FALSE;

  /* Initialize a memory manager instance for this object */
  jinit_memory_mgr((j_common_ptr) cinfo);

  /* Zero out pointers to permanent structures. */
  cinfo->progress = NULL;
  cinfo->dest = NULL;

  cinfo->comp_info = NULL;

  for (i = 0; i < NUM_QUANT_TBLS; i++) {
    cinfo->quant_tbl_ptrs[i] = NULL;
    cinfo->q_scale_factor[i] = 100;
  }

  for (i = 0; i < NUM_HUFF_TBLS; i++) {
    cinfo->dc_huff_tbl_ptrs[i] = NULL;
    cinfo->ac_huff_tbl_ptrs[i] = NULL;
  }

  /* Must do it here for emit_dqt in case jpeg_write_tables is used */
  cinfo->block_size = DCTSIZE;
  cinfo->natural_order = jpeg_natural_order;
  cinfo->lim_Se = DCTSIZE2-1;

  cinfo->script_space = NULL;

  cinfo->input_gamma = 1.0;	/* in case application forgets */

  /* OK, I'm ready */
  cinfo->global_state = CSTATE_START;
}


/*
 * Destruction of a JPEG compression object
 */

GLOBAL(void)
jpeg_destroy_compress (j_compress_ptr cinfo)
{
  jpeg_destroy((j_common_ptr) cinfo); /* use common routine */
}


/*
 * Abort processing of a JPEG compression operation,