jcomapi.c

/*
 * jcomapi.c
 *
 * Copyright (C) 1994-1997, Thomas G. Lane.
 * Modified 2019 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 routines that are used for both
 * compression and decompression.
 */

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


/*
 * Abort processing of a JPEG compression or decompression operation,
 * but don't destroy the object itself.
 *
 * For this, we merely clean up all the nonpermanent memory pools.
 * Note that temp files (virtual arrays) are not allowed to belong to
 * the permanent pool, so we will be able to close all temp files here.
 * Closing a data source or destination, if necessary, is the application's
 * responsibility.
 */

GLOBAL(void)
jpeg_abort (j_common_ptr cinfo)
{
  int pool;

  /* Do nothing if called on a not-initialized or destroyed JPEG object. */
  if (cinfo->mem == NULL)
    return;

  /* Releasing pools in reverse order might help avoid fragmentation
   * with some (brain-damaged) malloc libraries.
   */
  for (pool = JPOOL_NUMPOOLS-1; pool > JPOOL_PERMANENT; pool--) {
    (*cinfo->mem->free_pool) (cinfo, pool);
  }

  /* Reset overall state for possible reuse of object */
  if (cinfo->is_decompressor) {
    cinfo->global_state = DSTATE_START;
    /* Try to keep application from accessing now-deleted marker list.
     * A bit kludgy to do it here, but this is the most central place.
     */
    ((j_decompress_ptr) cinfo)->marker_list = NULL;
  } else {
    cinfo->global_state = CSTATE_START;
  }
}


/*
 * Destruction of a JPEG object.
 *
 * Everything gets deallocated except the master jpeg_compress_struct itself
 * and the error manager struct.  Both of these are supplied by the application
 * and must be freed, if necessary, by the application.  (Often they are on
 * the stack and so don't need to be freed anyway.)
 * Closing a data source or destination, if necessary, is the application's
 * responsibility.
 */

GLOBAL(void)
jpeg_destroy (j_common_ptr cinfo)
{
  /* We need only tell the memory manager to release everything. */
  /* NB: mem pointer is NULL if memory mgr failed to initialize. */
  if (cinfo->mem != NULL)
    (*cinfo->mem->self_destruct) (cinfo);
  cinfo->mem = NULL;		/* be safe if jpeg_destroy is called twice */
  cinfo->global_state = 0;	/* mark it destroyed */
}


/*
 * Convenience routines for allocating quantization and Huffman tables.
 * (Would jutils.c be a more reasonable place to put these?)
 */

GLOBAL(JQUANT_TBL *)
jpeg_alloc_quant_table (j_common_ptr cinfo)
{
  JQUANT_TBL *tbl;

  tbl = (JQUANT_TBL *)
    (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JQUANT_TBL));
  tbl->sent_table = FALSE;	/* make sure this is false in any new table */
  return tbl;
}


GLOBAL(JHUFF_TBL *)
jpeg_alloc_huff_table (j_common_ptr cinfo)
{
  JHUFF_TBL *tbl;

  tbl = (JHUFF_TBL *)
    (*cinfo->mem->alloc_small) (cinfo, JPOOL_PERMANENT, SIZEOF(JHUFF_TBL));
  tbl->sent_table = FALSE;	/* make sure this is false in any new table */
  return tbl;
}


/*
 * Set up the standard Huffman tables (cf. JPEG standard section K.3).
 * IMPORTANT: these are only valid for 8-bit data precision!
 * (Would jutils.c be a more reasonable place to put this?)
 */

GLOBAL(JHUFF_TBL *)
jpeg_std_huff_table (j_common_ptr cinfo, boolean isDC, int tblno)
{
  JHUFF_TBL **htblptr, *htbl;
  const UINT8 *bits, *val;
  int nsymbols, len;

  static const UINT8 bits_dc_luminance[17] =
    { /* 0-base */ 0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0 };
  static const UINT8 val_dc_luminance[] =
    { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };

  static const UINT8 bits_dc_chrominance[17] =
    { /* 0-base */ 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 };
  static const UINT8 val_dc_chrominance[] =
    { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };

  static const UINT8 bits_ac_luminance[17] =
    { /* 0-base */ 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d };
  static const UINT8 val_ac_luminance[] =
    { 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,
      0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,
      0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,
      0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0,
      0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16,
      0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,
      0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,
      0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,
      0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,
      0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,
      0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,
      0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,
      0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,
      0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
      0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,
      0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,
      0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,
      0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,
      0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,
      0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
      0xf9, 0xfa };

  static const UINT8 bits_ac_chrominance[17] =
    { /* 0-base */ 0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77 };
  static const UINT8 val_ac_chrominance[] =
    { 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,
      0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71,
      0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,
      0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0,
      0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34,
      0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26,
      0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38,
      0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,
      0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,
      0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,
      0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,
      0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
      0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,
      0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5,
      0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4,
      0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,
      0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2,
      0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,
      0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,
      0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,
      0xf9, 0xfa };

  if (cinfo->is_decompressor) {
    if (isDC)
      htblptr = ((j_decompress_ptr) cinfo)->dc_huff_tbl_ptrs;
    else
      htblptr = ((j_decompress_ptr) cinfo)->ac_huff_tbl_ptrs;
  } else {
    if (isDC)
      htblptr = ((j_compress_ptr) cinfo)->dc_huff_tbl_ptrs;
    else
      htblptr = ((j_compress_ptr) cinfo)->ac_huff_tbl_ptrs;
  }

  switch (tblno) {
  case 0:
    if (isDC) {
      bits = bits_dc_luminance;
      val = val_dc_luminance;
    } else {
      bits = bits_ac_luminance;
      val = val_ac_luminance;
    }
    break;
  case 1:
    if (isDC) {
      bits = bits_dc_chrominance;
      val = val_dc_chrominance;
    } else {
      bits = bits_ac_chrominance;
      val = val_ac_chrominance;
    }
    break;
  default:
    ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, tblno);
    return NULL; /* avoid compiler warnings for uninitialized variables */
  }

  if (htblptr[tblno] == NULL)
    htblptr[tblno] = jpeg_alloc_huff_table(cinfo);

  htbl = htblptr[tblno];

  /* Copy the number-of-symbols-of-each-code-length counts */
  MEMCOPY(htbl->bits, bits, SIZEOF(htbl->bits));

  /* Validate the counts.  We do this here mainly so we can copy the right
   * number of symbols from the val[] array, without risking marching off
   * the end of memory.  jxhuff.c will do a more thorough test later.
   */
  nsymbols = 0;
  for (len = 1; len <= 16; len++)
    nsymbols += bits[len];
  if (nsymbols > 256)
    ERREXIT(cinfo, JERR_BAD_HUFF_TABLE);

  if (nsymbols > 0)
    MEMCOPY(htbl->huffval, val, nsymbols * SIZEOF(UINT8));

  /* Initialize sent_table FALSE so table will be written to JPEG file. */
  htbl->sent_table = FALSE;

  return htbl;
}