jdapimin.cpp

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/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          http://www.mrpt.org/                          |
   |                                                                        |
   | Copyright (c) 2005-2017, Individual contributors, see AUTHORS file     |
   | See: http://www.mrpt.org/Authors - All rights reserved.                |
   | Released under BSD License. See details in http://www.mrpt.org/License |
   +------------------------------------------------------------------------+ */

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

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

GLOBAL(void)
jpeg_CreateDecompress(j_decompress_ptr cinfo, int version, size_t structsize)
{
        int i;

        /* Guard against version mismatches between library and caller. */
        cinfo->mem = nullptr; /* 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_decompress_struct))
                ERREXIT2(
                        cinfo, JERR_BAD_STRUCT_SIZE,
                        (int)SIZEOF(struct jpeg_decompress_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_decompress_struct));
                cinfo->err = err;
                cinfo->client_data = client_data;
        }
        cinfo->is_decompressor = TRUE;

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

        /* Zero out pointers to permanent structures. */
        cinfo->progress = nullptr;
        cinfo->src = nullptr;

        for (i = 0; i < NUM_QUANT_TBLS; i++) cinfo->quant_tbl_ptrs[i] = nullptr;

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

        /* Initialize marker processor so application can override methods
         * for COM, APPn markers before calling jpeg_read_header.
         */
        cinfo->marker_list = nullptr;
        jinit_marker_reader(cinfo);

        /* And initialize the overall input controller. */
        jinit_input_controller(cinfo);

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

/*
 * Destruction of a JPEG decompression object
 */

GLOBAL(void)
jpeg_destroy_decompress(j_decompress_ptr cinfo)
{
        jpeg_destroy((j_common_ptr)cinfo); /* use common routine */
}

/*
 * Abort processing of a JPEG decompression operation,
 * but don't destroy the object itself.
 */

GLOBAL(void)
jpeg_abort_decompress(j_decompress_ptr cinfo)
{
        jpeg_abort((j_common_ptr)cinfo); /* use common routine */
}

/*
 * Set default decompression parameters.
 */

LOCAL(void)
default_decompress_parms(j_decompress_ptr cinfo)
{
        /* Guess the input colorspace, and set output colorspace accordingly. */
        /* (Wish JPEG committee had provided a real way to specify this...) */
        /* Note application may override our guesses. */
        switch (cinfo->num_components)
        {
                case 1:
                        cinfo->jpeg_color_space = JCS_GRAYSCALE;
                        cinfo->out_color_space = JCS_GRAYSCALE;
                        break;

                case 3:
                        if (cinfo->saw_JFIF_marker)
                        {
                                cinfo->jpeg_color_space = JCS_YCbCr; /* JFIF implies YCbCr */
                        }
                        else if (cinfo->saw_Adobe_marker)
                        {
                                switch (cinfo->Adobe_transform)
                                {
                                        case 0:
                                                cinfo->jpeg_color_space = JCS_RGB;
                                                break;
                                        case 1:
                                                cinfo->jpeg_color_space = JCS_YCbCr;
                                                break;
                                        default:
                                                WARNMS1(
                                                        cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform);
                                                cinfo->jpeg_color_space =
                                                        JCS_YCbCr; /* assume it's YCbCr */
                                                break;
                                }
                        }
                        else
                        {
                                /* Saw no special markers, try to guess from the component IDs
                                 */
                                int cid0 = cinfo->comp_info[0].component_id;
                                int cid1 = cinfo->comp_info[1].component_id;
                                int cid2 = cinfo->comp_info[2].component_id;

                                if (cid0 == 1 && cid1 == 2 && cid2 == 3)
                                        cinfo->jpeg_color_space =
                                                JCS_YCbCr; /* assume JFIF w/out marker */
                                else if (cid0 == 82 && cid1 == 71 && cid2 == 66)
                                        cinfo->jpeg_color_space = JCS_RGB; /* ASCII 'R', 'G', 'B' */
                                else
                                {
                                        TRACEMS3(cinfo, 1, JTRC_UNKNOWN_IDS, cid0, cid1, cid2);
                                        cinfo->jpeg_color_space = JCS_YCbCr; /* assume it's YCbCr */
                                }
                        }
                        /* Always guess RGB is proper output colorspace. */
                        cinfo->out_color_space = JCS_RGB;
                        break;

                case 4:
                        if (cinfo->saw_Adobe_marker)
                        {
                                switch (cinfo->Adobe_transform)
                                {
                                        case 0:
                                                cinfo->jpeg_color_space = JCS_CMYK;
                                                break;
                                        case 2:
                                                cinfo->jpeg_color_space = JCS_YCCK;
                                                break;
                                        default:
                                                WARNMS1(
                                                        cinfo, JWRN_ADOBE_XFORM, cinfo->Adobe_transform);
                                                cinfo->jpeg_color_space =
                                                        JCS_YCCK; /* assume it's YCCK */
                                                break;
                                }
                        }
                        else
                        {
                                /* No special markers, assume straight CMYK. */
                                cinfo->jpeg_color_space = JCS_CMYK;
                        }
                        cinfo->out_color_space = JCS_CMYK;
                        break;

                default:
                        cinfo->jpeg_color_space = JCS_UNKNOWN;
                        cinfo->out_color_space = JCS_UNKNOWN;
                        break;
        }

        /* Set defaults for other decompression parameters. */
        cinfo->scale_num = 1; /* 1:1 scaling */
        cinfo->scale_denom = 1;
        cinfo->output_gamma = 1.0;
        cinfo->buffered_image = FALSE;
        cinfo->raw_data_out = FALSE;
        cinfo->dct_method = JDCT_DEFAULT;
        cinfo->do_fancy_upsampling = TRUE;
        cinfo->do_block_smoothing = TRUE;
        cinfo->quantize_colors = FALSE;
        /* We set these in case application only sets quantize_colors. */
        cinfo->dither_mode = JDITHER_FS;
#ifdef QUANT_2PASS_SUPPORTED
        cinfo->two_pass_quantize = TRUE;
#else
        cinfo->two_pass_quantize = FALSE;
#endif
        cinfo->desired_number_of_colors = 256;
        cinfo->colormap = nullptr;
        /* Initialize for no mode change in buffered-image mode. */
        cinfo->enable_1pass_quant = FALSE;
        cinfo->enable_external_quant = FALSE;
        cinfo->enable_2pass_quant = FALSE;
}

/*
 * Decompression startup: read start of JPEG datastream to see what's there.
 * Need only initialize JPEG object and supply a data source before calling.
 *
 * This routine will read as far as the first SOS marker (ie, actual start of
 * compressed data), and will save all tables and parameters in the JPEG
 * object.  It will also initialize the decompression parameters to default
 * values, and finally return JPEG_HEADER_OK.  On return, the application may
 * adjust the decompression parameters and then call jpeg_start_decompress.
 * (Or, if the application only wanted to determine the image parameters,
 * the data need not be decompressed.  In that case, call jpeg_abort or
 * jpeg_destroy to release any temporary space.)
 * If an abbreviated (tables only) datastream is presented, the routine will
 * return JPEG_HEADER_TABLES_ONLY upon reaching EOI.  The application may then
 * re-use the JPEG object to read the abbreviated image datastream(s).
 * It is unnecessary (but OK) to call jpeg_abort in this case.
 * The JPEG_SUSPENDED return code only occurs if the data source module
 * requests suspension of the decompressor.  In this case the application
 * should load more source data and then re-call jpeg_read_header to resume
 * processing.
 * If a non-suspending data source is used and require_image is TRUE, then the
 * return code need not be inspected since only JPEG_HEADER_OK is possible.
 *
 * This routine is now just a front end to jpeg_consume_input, with some
 * extra error checking.
 */

GLOBAL(int)
jpeg_read_header(j_decompress_ptr cinfo, boolean require_image)
{
        int retcode;

        if (cinfo->global_state != DSTATE_START &&
                cinfo->global_state != DSTATE_INHEADER)
                ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);

        retcode = jpeg_consume_input(cinfo);

        switch (retcode)
        {
                case JPEG_REACHED_SOS:
                        retcode = JPEG_HEADER_OK;
                        break;
                case JPEG_REACHED_EOI:
                        if (require_image) /* Complain if application wanted an image */
                                ERREXIT(cinfo, JERR_NO_IMAGE);
                        /* Reset to start state; it would be safer to require the
                         * application to
                         * call jpeg_abort, but we can't change it now for compatibility
                         * reasons.
                         * A side effect is to free any temporary memory (there shouldn't be
                         * any).
                         */
                        jpeg_abort((j_common_ptr)cinfo); /* sets state = DSTATE_START */
                        retcode = JPEG_HEADER_TABLES_ONLY;
                        break;
                case JPEG_SUSPENDED:
                        /* no work */
                        break;
        }

        return retcode;
}

/*
 * Consume data in advance of what the decompressor requires.
 * This can be called at any time once the decompressor object has
 * been created and a data source has been set up.
 *
 * This routine is essentially a state machine that handles a couple
 * of critical state-transition actions, namely initial setup and
 * transition from header scanning to ready-for-start_decompress.
 * All the actual input is done via the input controller's consume_input
 * method.
 */

GLOBAL(int)
jpeg_consume_input(j_decompress_ptr cinfo)
{
        int retcode = JPEG_SUSPENDED;

        /* NB: every possible DSTATE value should be listed in this switch */
        switch (cinfo->global_state)
        {
                case DSTATE_START:
                        /* Start-of-datastream actions: reset appropriate modules */
                        (*cinfo->inputctl->reset_input_controller)(cinfo);
                        /* Initialize application's data source module */
                        (*cinfo->src->init_source)(cinfo);
                        cinfo->global_state = DSTATE_INHEADER;
                /*FALLTHROUGH*/
                case DSTATE_INHEADER:
                        retcode = (*cinfo->inputctl->consume_input)(cinfo);
                        if (retcode == JPEG_REACHED_SOS)
                        { /* Found SOS, prepare to decompress */
                                /* Set up default parameters based on header data */
                                default_decompress_parms(cinfo);
                                /* Set global state: ready for start_decompress */
                                cinfo->global_state = DSTATE_READY;
                        }
                        break;
                case DSTATE_READY:
                        /* Can't advance past first SOS until start_decompress is called */
                        retcode = JPEG_REACHED_SOS;
                        break;
                case DSTATE_PRELOAD:
                case DSTATE_PRESCAN:
                case DSTATE_SCANNING:
                case DSTATE_RAW_OK:
                case DSTATE_BUFIMAGE:
                case DSTATE_BUFPOST:
                case DSTATE_STOPPING:
                        retcode = (*cinfo->inputctl->consume_input)(cinfo);
                        break;
                default:
                        ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
        }
        return retcode;
}

/*
 * Have we finished reading the input file?
 */

GLOBAL(boolean)
jpeg_input_complete(j_decompress_ptr cinfo)
{
        /* Check for valid jpeg object */
        if (cinfo->global_state < DSTATE_START ||
                cinfo->global_state > DSTATE_STOPPING)
                ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
        return cinfo->inputctl->eoi_reached;
}

/*
 * Is there more than one scan?
 */

GLOBAL(boolean)
jpeg_has_multiple_scans(j_decompress_ptr cinfo)
{
        /* Only valid after jpeg_read_header completes */
        if (cinfo->global_state < DSTATE_READY ||
                cinfo->global_state > DSTATE_STOPPING)
                ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
        return cinfo->inputctl->has_multiple_scans;
}

/*
 * Finish JPEG decompression.
 *
 * This will normally just verify the file trailer and release temp storage.
 *
 * Returns FALSE if suspended.  The return value need be inspected only if
 * a suspending data source is used.
 */

GLOBAL(boolean)
jpeg_finish_decompress(j_decompress_ptr cinfo)
{
        if ((cinfo->global_state == DSTATE_SCANNING ||
                 cinfo->global_state == DSTATE_RAW_OK) &&
                !cinfo->buffered_image)
        {
                /* Terminate final pass of non-buffered mode */
                if (cinfo->output_scanline < cinfo->output_height)
                        ERREXIT(cinfo, JERR_TOO_LITTLE_DATA);
                (*cinfo->master->finish_output_pass)(cinfo);
                cinfo->global_state = DSTATE_STOPPING;
        }
        else if (cinfo->global_state == DSTATE_BUFIMAGE)
        {
                /* Finishing after a buffered-image operation */
                cinfo->global_state = DSTATE_STOPPING;
        }
        else if (cinfo->global_state != DSTATE_STOPPING)
        {
                /* STOPPING = repeat call after a suspension, anything else is error */
                ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
        }
        /* Read until EOI */
        while (!cinfo->inputctl->eoi_reached)
        {
                if ((*cinfo->inputctl->consume_input)(cinfo) == JPEG_SUSPENDED)
                        return FALSE; /* Suspend, come back later */
        }
        /* Do final cleanup */
        (*cinfo->src->term_source)(cinfo);
        /* We can use jpeg_abort to release memory and reset global_state */
        jpeg_abort((j_common_ptr)cinfo);
        return TRUE;
}