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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;

 #if JPEG_LIB_VERSION >= 70

     cinfo->q_scale_factor[i] = 100;

 #endif

   }

   for (i = 0; i < NUM_HUFF_TBLS; i++) {

     cinfo->dc_huff_tbl_ptrs[i] = NULL;

     cinfo->ac_huff_tbl_ptrs[i] = NULL;

   }

 #if JPEG_LIB_VERSION >= 80

   /* 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;

 #endif

   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,

  * but don't destroy the object itself.

  */

 GLOBAL(void)

 jpeg_abort_compress (j_compress_ptr cinfo)

 {

   jpeg_abort((j_common_ptr) cinfo); /* use common routine */

 }

 /*

  * Forcibly suppress or un-suppress all quantization and Huffman tables.

  * Marks all currently defined tables as already written (if suppress)

  * or not written (if !suppress).  This will control whether they get emitted

  * by a subsequent jpeg_start_compress call.

  *

  * This routine is exported for use by applications that want to produce

  * abbreviated JPEG datastreams.  It logically belongs in jcparam.c, but

  * since it is called by jpeg_start_compress, we put it here --- otherwise

  * jcparam.o would be linked whether the application used it or not.

  */

 GLOBAL(void)

 jpeg_suppress_tables (j_compress_ptr cinfo, boolean suppress)

 {

   int i;

   JQUANT_TBL * qtbl;

   JHUFF_TBL * htbl;

   for (i = 0; i < NUM_QUANT_TBLS; i++) {

     if ((qtbl = cinfo->quant_tbl_ptrs[i]) != NULL)

       qtbl->sent_table = suppress;

   }

   for (i = 0; i < NUM_HUFF_TBLS; i++) {

     if ((htbl = cinfo->dc_huff_tbl_ptrs[i]) != NULL)

       htbl->sent_table = suppress;

     if ((htbl = cinfo->ac_huff_tbl_ptrs[i]) != NULL)

       htbl->sent_table = suppress;

   }

 }

 /*

  * Finish JPEG compression.

  *

  * If a multipass operating mode was selected, this may do a great deal of

  * work including most of the actual output.

  */

 GLOBAL(void)

 jpeg_finish_compress (j_compress_ptr cinfo)

 {

   JDIMENSION iMCU_row;

   if (cinfo->global_state == CSTATE_SCANNING ||

       cinfo->global_state == CSTATE_RAW_OK) {

     /* Terminate first pass */

     if (cinfo->next_scanline < cinfo->image_height)

       ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);

     (*cinfo->master->finish_pass) (cinfo);

   } else if (cinfo->global_state != CSTATE_WRCOEFS)

     ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

   /* Perform any remaining passes */

   while (! cinfo->master->is_last_pass) {

     (*cinfo->master->prepare_for_pass) (cinfo);

     for (iMCU_row = 0; iMCU_row < cinfo->total_iMCU_rows; iMCU_row++) {

       if (cinfo->progress != NULL) {

 	cinfo->progress->pass_counter = (long) iMCU_row;

 	cinfo->progress->pass_limit = (long) cinfo->total_iMCU_rows;

 	(*cinfo->progress->progress_monitor) ((j_common_ptr) cinfo);

       }

       /* We bypass the main controller and invoke coef controller directly;

        * all work is being done from the coefficient buffer.

        */

       if (! (*cinfo->coef->compress_data) (cinfo, (JSAMPIMAGE) NULL))

 	ERREXIT(cinfo, JERR_CANT_SUSPEND);

     }

     (*cinfo->master->finish_pass) (cinfo);

   }

   /* Write EOI, do final cleanup */

   (*cinfo->marker->write_file_trailer) (cinfo);

   (*cinfo->dest->term_destination) (cinfo);

   /* We can use jpeg_abort to release memory and reset global_state */

   jpeg_abort((j_common_ptr) cinfo);

 }

 /*

  * Write a special marker.

  * This is only recommended for writing COM or APPn markers.

  * Must be called after jpeg_start_compress() and before

  * first call to jpeg_write_scanlines() or jpeg_write_raw_data().

  */

 GLOBAL(void)

 jpeg_write_marker (j_compress_ptr cinfo, int marker,

 		   const JOCTET *dataptr, unsigned int datalen)

 {

   JMETHOD(void, write_marker_byte, (j_compress_ptr info, int val));

   if (cinfo->next_scanline != 0 ||

       (cinfo->global_state != CSTATE_SCANNING &&

        cinfo->global_state != CSTATE_RAW_OK &&

        cinfo->global_state != CSTATE_WRCOEFS))

     ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

   (*cinfo->marker->write_marker_header) (cinfo, marker, datalen);

   write_marker_byte = cinfo->marker->write_marker_byte;	/* copy for speed */

   while (datalen--) {

     (*write_marker_byte) (cinfo, *dataptr);

     dataptr++;

   }

 }

 /* Same, but piecemeal. */

 GLOBAL(void)

 jpeg_write_m_header (j_compress_ptr cinfo, int marker, unsigned int datalen)

 {

   if (cinfo->next_scanline != 0 ||

       (cinfo->global_state != CSTATE_SCANNING &&

        cinfo->global_state != CSTATE_RAW_OK &&

        cinfo->global_state != CSTATE_WRCOEFS))

     ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

   (*cinfo->marker->write_marker_header) (cinfo, marker, datalen);

 }

 GLOBAL(void)

 jpeg_write_m_byte (j_compress_ptr cinfo, int val)

 {

   (*cinfo->marker->write_marker_byte) (cinfo, val);

 }

 /*

  * Alternate compression function: just write an abbreviated table file.

  * Before calling this, all parameters and a data destination must be set up.

  *

  * To produce a pair of files containing abbreviated tables and abbreviated

  * image data, one would proceed as follows:

  *

  *		initialize JPEG object

  *		set JPEG parameters

  *		set destination to table file

  *		jpeg_write_tables(cinfo);

  *		set destination to image file

  *		jpeg_start_compress(cinfo, FALSE);

  *		write data...

  *		jpeg_finish_compress(cinfo);

  *

  * jpeg_write_tables has the side effect of marking all tables written

  * (same as jpeg_suppress_tables(..., TRUE)).  Thus a subsequent start_compress

  * will not re-emit the tables unless it is passed write_all_tables=TRUE.

  */

 GLOBAL(void)

 jpeg_write_tables (j_compress_ptr cinfo)

 {

   if (cinfo->global_state != CSTATE_START)

     ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

   /* (Re)initialize error mgr and destination modules */

   (*cinfo->err->reset_error_mgr) ((j_common_ptr) cinfo);

   (*cinfo->dest->init_destination) (cinfo);

   /* Initialize the marker writer ... bit of a crock to do it here. */

   jinit_marker_writer(cinfo);

   /* Write them tables! */

   (*cinfo->marker->write_tables_only) (cinfo);

   /* And clean up. */

   (*cinfo->dest->term_destination) (cinfo);

   /*

    * In library releases up through v6a, we called jpeg_abort() here to free

    * any working memory allocated by the destination manager and marker

    * writer.  Some applications had a problem with that: they allocated space

    * of their own from the library memory manager, and didn't want it to go

    * away during write_tables.  So now we do nothing.  This will cause a

    * memory leak if an app calls write_tables repeatedly without doing a full

    * compression cycle or otherwise resetting the JPEG object.  However, that

    * seems less bad than unexpectedly freeing memory in the normal case.

    * An app that prefers the old behavior can call jpeg_abort for itself after

    * each call to jpeg_write_tables().

    */

 }