src/jcmaster.h

/*
 * jcmaster.h
 *
 * This file was part of the Independent JPEG Group's software:
 * Copyright (C) 1991-1995, Thomas G. Lane.
 * libjpeg-turbo Modifications:
 * Copyright (C) 2016, D. R. Commander.
 * For conditions of distribution and use, see the accompanying README.ijg
 * file.
 *
 * This file contains master control structure for the JPEG compressor.
 */

/* Private state */

typedef enum {
  main_pass,                    /* input data, also do first output step */
  huff_opt_pass,                /* Huffman code optimization pass */
  output_pass                   /* data output pass */
} c_pass_type;

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

  c_pass_type pass_type;        /* the type of the current pass */

  int pass_number;              /* # of passes completed */
  int total_passes;             /* total # of passes needed */

  int scan_number;              /* current index in scan_info[] */

  /*
   * This is here so we can add libjpeg-turbo version/build information to the
   * global string table without introducing a new global symbol.  Adding this
   * information to the global string table allows one to examine a binary
   * object and determine which version of libjpeg-turbo it was built from or
   * linked against.
   */
  const char *jpeg_version;

} my_comp_master;

typedef my_comp_master *my_master_ptr;