/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* Copyright by The HDF Group.                                               *
* Copyright by the Board of Trustees of the University of Illinois.         *
* All rights reserved.                                                      *
*                                                                           *
* This file is part of HDF5.  The full HDF5 copyright notice, including     *
* terms governing use, modification, and redistribution, is contained in    *
* the files COPYING and Copyright.html.  COPYING can be found at the root   *
* of the source code distribution tree; Copyright.html can be found at the  *
* root level of an installed copy of the electronic HDF5 document set and   *
* is linked from the top-level documents page.  It can also be found at     *
* http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
* access to either file, you may request a copy from help@hdfgroup.org.     *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#include "H5IMprivate.h"
#include "H5LTprivate.h"
#include <string.h>
#include <stdlib.h>

/*-------------------------------------------------------------------------
* Function: H5IMmake_image_8bit
*
* Purpose: Creates and writes an image an 8 bit image
*
* Return: Success: 0, Failure: -1
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: June 13, 2001
*
* Comments:
*  based on HDF5 Image and Palette Specification
*  http://hdf.ncsa.uiuc.edu/HDF5/H5Image/ImageSpec.html
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IMmake_image_8bit( hid_t loc_id,
                           const char *dset_name,
                           hsize_t width,
                           hsize_t height,
                           const unsigned char *buf )
{
    hsize_t  dims[IMAGE8_RANK];

    /* check the arguments */
    if (dset_name == NULL) 
        return -1;

    /* Initialize the image dimensions */
    dims[0] = height;
    dims[1] = width;

    /* Make the dataset */
    if ( H5LTmake_dataset( loc_id, dset_name, IMAGE8_RANK, dims, H5T_NATIVE_UCHAR, buf ) < 0)
        return -1;

    /* Attach the CLASS attribute */
    if ( H5LTset_attribute_string( loc_id, dset_name, "CLASS", IMAGE_CLASS ) < 0)
        return -1;

    /* Attach the VERSION attribute */
    if ( H5LTset_attribute_string( loc_id, dset_name, "IMAGE_VERSION", IMAGE_VERSION ) < 0)
        return -1;

    /* Attach the IMAGE_SUBCLASS attribute */
    if ( H5LTset_attribute_string( loc_id, dset_name, "IMAGE_SUBCLASS", "IMAGE_INDEXED" ) < 0)
        return -1;

    return 0;
}

/*-------------------------------------------------------------------------
* Function: H5IMmake_image_24bit
*
* Purpose:
*
* Return: Success: 0, Failure: -1
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: June 13, 2001
*
* Comments:
*  based on HDF5 Image and Palette Specification
*  http://hdf.ncsa.uiuc.edu/HDF5/H5Image/ImageSpec.html
*
* Interlace Mode Dimensions in the Dataspace
* INTERLACE_PIXEL [height][width][pixel components]
* INTERLACE_PLANE [pixel components][height][width]
*
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IMmake_image_24bit( hid_t loc_id,
                            const char *dset_name,
                            hsize_t width,
                            hsize_t height,
                            const char *interlace,
                            const unsigned char *buf )
{
    hsize_t  dims[IMAGE24_RANK];

    /* check the arguments */
    if (interlace == NULL) 
        return -1;
    if (dset_name == NULL) 
        return -1;


    /* Initialize the image dimensions */

    if ( HDstrncmp( interlace, "INTERLACE_PIXEL",15 ) == 0 )
    {
        /* Number of color planes is defined as the third dimension */
        dims[0] = height;
        dims[1] = width;
        dims[2] = IMAGE24_RANK;
    }
    else
      if ( HDstrncmp( interlace, "INTERLACE_PLANE",15 ) == 0 )
        {
            /* Number of color planes is defined as the first dimension */
            dims[0] = IMAGE24_RANK;
            dims[1] = height;
            dims[2] = width;
        }
        else return -1;

        /* Make the dataset */
        if ( H5LTmake_dataset( loc_id, dset_name, IMAGE24_RANK, dims, H5T_NATIVE_UCHAR, buf ) < 0)
            return -1;

        /* Attach the CLASS attribute */
        if ( H5LTset_attribute_string( loc_id, dset_name, "CLASS", IMAGE_CLASS ) < 0)
            return -1;

        /* Attach the VERSION attribute */
        if ( H5LTset_attribute_string( loc_id, dset_name, "IMAGE_VERSION", IMAGE_VERSION ) < 0)
            return -1;

        /* Attach the IMAGE_SUBCLASS attribute */
        if ( H5LTset_attribute_string( loc_id, dset_name, "IMAGE_SUBCLASS", "IMAGE_TRUECOLOR" ) < 0)
            return -1;

        /* Attach the INTERLACE_MODE attribute. This attributes is only for true color images */
        if ( H5LTset_attribute_string( loc_id, dset_name, "INTERLACE_MODE", interlace ) < 0)
            return -1;

        return 0;

}



/*-------------------------------------------------------------------------
* Function: find_palette
*
* Purpose: operator function used by H5LT_find_palette
*
* Return:
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: May 28, 2001
*
* Comments:
*
* Modifications:
*
*-------------------------------------------------------------------------
*/
static herr_t find_palette(hid_t loc_id,
                           const char *name,
                           const H5A_info_t *ainfo,
                           void *op_data)
{
    int ret = H5_ITER_CONT;

    /* check the arguments */
    if (name == NULL) 
        return -1;

    /* Shut compiler up */
    loc_id = loc_id; ainfo = ainfo; op_data = op_data;

    /* Define a positive value for return value if the attribute was found. This will
    * cause the iterator to immediately return that positive value,
    * indicating short-circuit success
    */
    if(HDstrncmp(name, "PALETTE",7) == 0)
        ret = H5_ITER_STOP;

    return ret;
}


/*-------------------------------------------------------------------------
* Function: H5IM_find_palette
*
* Purpose: Private function. Find the attribute "PALETTE" in the image dataset
*
* Return: Success: 1, Failure: 0
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: May 11, 2001
*
* Comments:
*  The function uses H5Aiterate2 with the operator function find_palette
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IM_find_palette( hid_t loc_id )
{
    return H5Aiterate2(loc_id, H5_INDEX_NAME, H5_ITER_INC, NULL, find_palette, NULL);
}


/*-------------------------------------------------------------------------
* Function: H5IMget_image_info
*
* Purpose: Gets information about an image dataset (dimensions, interlace mode
*          and number of associated palettes).
*
* Return: Success: 0, Failure: -1
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: July 25, 2001
*
* Comments:
*  based on HDF5 Image and Palette Specification
*  http://hdf.ncsa.uiuc.edu/HDF5/H5Image/ImageSpec.html
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IMget_image_info( hid_t loc_id,
                          const char *dset_name,
                          hsize_t *width,
                          hsize_t *height,
                          hsize_t *planes,
                          char *interlace,
                          hssize_t *npals )
{
    hid_t       did                     = -1;
    hid_t       sid                     = -1;
    hsize_t     dims[IMAGE24_RANK];
    hid_t       aid                     = -1;
    hid_t       asid                    = -1;
    hid_t       atid                    = -1;
    H5T_class_t aclass;
    int         has_pal;
    int         has_attr;

    /* check the arguments */
    if (dset_name == NULL) 
      return -1;
    if (interlace == NULL) 
      return -1;

    /*assume initially we have no palettes attached*/
    *npals = 0;

    /* Open the dataset. */
    if((did = H5Dopen2(loc_id, dset_name, H5P_DEFAULT)) < 0)
        return -1;

    /* Try to find the attribute "INTERLACE_MODE" on the >>image<< dataset */
    has_attr = H5LT_find_attribute(did, "INTERLACE_MODE");

    /* It exists, get it */
    if(has_attr == 1)
    {

        if((aid = H5Aopen(did, "INTERLACE_MODE", H5P_DEFAULT)) < 0)
            goto out;

        if((atid = H5Aget_type(aid)) < 0)
            goto out;

        if(H5Aread(aid, atid, interlace) < 0)
            goto out;

        if(H5Tclose(atid) < 0)
            goto out;

        if(H5Aclose(aid) < 0)
            goto out;
    }

    /* Get the dataspace handle */
    if ( (sid = H5Dget_space( did )) < 0)
        goto out;

    /* Get dimensions */
    if ( H5Sget_simple_extent_dims( sid, dims, NULL) < 0)
        goto out;

    /* Initialize the image dimensions */

    if ( has_attr == 1 )
        /* This is a 24 bit image */
    {

      if ( HDstrncmp( interlace, "INTERLACE_PIXEL", 15 ) == 0 )
        {
            /* Number of color planes is defined as the third dimension */
            *height = dims[0];
            *width  = dims[1];
            *planes = dims[2];
        }
        else
	  if ( HDstrncmp( interlace, "INTERLACE_PLANE", 15 ) == 0 )
            {
                /* Number of color planes is defined as the first dimension */
                *planes = dims[0];
                *height = dims[1];
                *width  = dims[2];
            }
	  else return -1;
    }
    else
        /* This is a 8 bit image */
    {
        *height = dims[0];
        *width  = dims[1];
        *planes = 1;
    }

    /* Close */
    if ( H5Sclose( sid ) < 0)
        goto out;


    /* Get number of palettes */


    /* Try to find the attribute "PALETTE" on the >>image<< dataset */
    has_pal = H5IM_find_palette(did);

    if(has_pal ==  1)
    {

        if((aid = H5Aopen(did, "PALETTE", H5P_DEFAULT)) < 0)
            goto out;

        if((atid = H5Aget_type(aid)) < 0)
            goto out;

        if((aclass = H5Tget_class(atid)) < 0)
            goto out;

        /* Check if it is really a reference */

        if(aclass == H5T_REFERENCE)
        {

            /* Get the reference(s) */

            if ( (asid = H5Aget_space( aid )) < 0)
                goto out;

            *npals = H5Sget_simple_extent_npoints( asid );

            if ( H5Sclose( asid ) < 0)
                goto out;

        } /* H5T_REFERENCE */

        if ( H5Tclose( atid ) < 0)
            goto out;

        /* Close the attribute. */
        if ( H5Aclose( aid ) < 0)
            goto out;

    }

    /* End access to the dataset and release resources used by it. */
    if ( H5Dclose( did ) < 0)
        goto out;

    return 0;

out:
    if(did > 0)
        H5Dclose( did );
    if(aid > 0)
        H5Aclose( aid );
    if(asid > 0)
        H5Sclose( asid );
    if(atid > 0)
        H5Tclose( atid );
    return -1;

}


/*-------------------------------------------------------------------------
* Function: H5IMread_image
*
* Purpose: Reads image data from disk.
*
* Return: Success: 0, Failure: -1
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: June 13, 2001
*
* Comments:
*  based on HDF5 Image and Palette Specification
*  http://hdf.ncsa.uiuc.edu/HDF5/H5Image/ImageSpec.html
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IMread_image( hid_t loc_id,
                       const char *dset_name,
                       unsigned char *buf )
{
    hid_t   did;

    /* check the arguments */
    if (dset_name == NULL) 
      return -1;

    /* Open the dataset. */
    if((did = H5Dopen2(loc_id, dset_name, H5P_DEFAULT)) < 0)
        return -1;

    /* Read */
    if ( H5Dread( did, H5T_NATIVE_UCHAR, H5S_ALL, H5S_ALL, H5P_DEFAULT, buf ) < 0)
        goto out;

    /* End access to the dataset and release resources used by it. */
    if ( H5Dclose( did ) )
        return -1;

    return 0;

out:
    H5Dclose( did );
    return -1;

}


/*-------------------------------------------------------------------------
* Function: H5IMmake_palette
*
* Purpose: Creates and writes a palette.
*
* Return: Success: 0, Failure: -1
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: May 01, 2001
*
* Comments:
*  based on HDF5 Image and Palette Specification
*  http://hdf.ncsa.uiuc.edu/HDF5/H5Image/ImageSpec.html
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IMmake_palette( hid_t loc_id,
                        const char *pal_name,
                        const hsize_t *pal_dims,
                        const unsigned char *pal_data )

{

    int has_pal;

    /* check the arguments */
    if (pal_name == NULL) 
      return -1;

    /* Check if the dataset already exists */
    has_pal = H5LTfind_dataset( loc_id, pal_name );

    /* It exists. Return */
    if ( has_pal == 1 )
        return 0;

    /* Make the palette dataset. */
    if ( H5LTmake_dataset( loc_id, pal_name, 2, pal_dims, H5T_NATIVE_UCHAR, pal_data ) <  0 )
        return -1;

    /* Attach the attribute "CLASS" to the >>palette<< dataset*/
    if ( H5LTset_attribute_string( loc_id, pal_name, "CLASS", PALETTE_CLASS ) < 0)
        return -1;

    /* Attach the attribute "PAL_VERSION" to the >>palette<< dataset*/
    if ( H5LTset_attribute_string( loc_id, pal_name, "PAL_VERSION", "1.2" ) < 0)
        return -1;

    return 0;

}


/*-------------------------------------------------------------------------
* Function: H5IMlink_palette
*
* Purpose: This function attaches a palette to an existing image dataset
*
* Return: Success: 0, Failure: -1
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: May 01, 2001
*
* Comments:
*  based on HDF5 Image and Palette Specification
*  http://hdf.ncsa.uiuc.edu/HDF5/H5Image/ImageSpec.html
*
*  An image (dataset) within an HDF5 file may optionally specify an array of
*  palettes to be viewed with. The dataset will have an attribute
*  which contains an array of object reference pointers which refer to palettes in the file.
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IMlink_palette( hid_t loc_id,
                        const char *image_name,
                        const char *pal_name )

{
    hid_t       did;
    hid_t       atid=-1;
    hid_t       aid=-1;
    hid_t       asid=-1;
    hobj_ref_t  ref;         /* write a new reference */
    hobj_ref_t  *refbuf;     /* buffer to read references */
    hssize_t    n_refs;
    hsize_t     dim_ref;
    int         ok_pal;

    
    /* check the arguments */
    if (image_name == NULL) 
      return -1;
    if (pal_name == NULL) 
      return -1;

    /* The image dataset may or may not have the attribute "PALETTE"
    * First we try to open to see if it is already there; if not, it is created.
    * If it exists, the array of references is extended to hold the reference
    * to the new palette
    */

    /* First we get the image id */
    if((did = H5Dopen2(loc_id, image_name, H5P_DEFAULT)) < 0)
        return -1;

    /* Try to find the attribute "PALETTE" on the >>image<< dataset */
    ok_pal = H5LT_find_attribute( did, "PALETTE" );

    /*-------------------------------------------------------------------------
    * It does not exist. We create the attribute and one reference
    *-------------------------------------------------------------------------
    */
    if(ok_pal == 0 )
    {
        if((asid = H5Screate(H5S_SCALAR)) < 0)
            goto out;

        /* Create the attribute type for the reference */
        if((atid = H5Tcopy(H5T_STD_REF_OBJ)) < 0)
            goto out;

        /* Create the attribute "PALETTE" to be attached to the image*/
        if((aid = H5Acreate2(did, "PALETTE", atid, asid, H5P_DEFAULT, H5P_DEFAULT)) < 0)
            goto out;

        /* Create a reference. The reference is created on the local id.  */
        if(H5Rcreate(&ref, loc_id, pal_name, H5R_OBJECT, (hid_t)-1) < 0)
            goto out;

        /* Write the attribute with the reference */
        if(H5Awrite(aid, atid, &ref) < 0)
            goto out;

        /* close */
        if(H5Sclose(asid) < 0)
            goto out;
        if(H5Tclose(atid) < 0)
            goto out;
        if(H5Aclose(aid) < 0)
            goto out;

    }

    /*-------------------------------------------------------------------------
    * The attribute already exists, open it
    *-------------------------------------------------------------------------
    */
    else if(ok_pal ==  1)
    {
        if((aid = H5Aopen(did, "PALETTE", H5P_DEFAULT)) < 0)
            goto out;

        if((atid = H5Aget_type(aid)) < 0)
            goto out;

        if(H5Tget_class(atid) < 0)
            goto out;

        /* Get and save the old reference(s) */
        if((asid = H5Aget_space(aid)) < 0)
            goto out;

        n_refs = H5Sget_simple_extent_npoints(asid);

        dim_ref = (hsize_t)n_refs + 1;

        refbuf = (hobj_ref_t*)HDmalloc( sizeof(hobj_ref_t) * (size_t)dim_ref );

        if ( H5Aread( aid, atid, refbuf ) < 0)
            goto out;

        /* The attribute must be deleted, in order to the new one can reflect the changes*/
        if(H5Adelete(did, "PALETTE") < 0)
            goto out;

        /* Create a new reference for this palette. */
        if ( H5Rcreate( &ref, loc_id, pal_name, H5R_OBJECT, (hid_t)-1 ) < 0)
            goto out;

        refbuf[n_refs] = ref;

        /* Create the data space for the new references */
        if(H5Sclose(asid) < 0)
            goto out;

        if((asid = H5Screate_simple(1, &dim_ref, NULL)) < 0)
            goto out;

        /* Create the attribute again with the changes of space */
        if(H5Aclose(aid) < 0)
            goto out;

        if((aid = H5Acreate2(did, "PALETTE", atid, asid, H5P_DEFAULT, H5P_DEFAULT)) < 0)
            goto out;

        /* Write the attribute with the new references */
        if(H5Awrite(aid, atid, refbuf) < 0)
            goto out;

        /* close */
        if(H5Sclose(asid) < 0)
            goto out;
        if(H5Tclose(atid) < 0)
            goto out;
        if(H5Aclose(aid) < 0)
            goto out;

        HDfree( refbuf );

    } /* ok_pal ==  1 */

    /* Close the image dataset. */
    if ( H5Dclose( did ) < 0)
        return -1;

    return 0;

out:
    H5Dclose( did );
    H5Sclose( asid );
    H5Tclose( atid );
    H5Aclose( aid );
    return -1;
}



/*-------------------------------------------------------------------------
* Function: H5IMunlink_palette
*
* Purpose: This function dettaches a palette from an existing image dataset
*
* Return: Success: 0, Failure: -1
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: September 10, 2001
*
* Comments:
*  based on HDF5 Image and Palette Specification
*  http://hdf.ncsa.uiuc.edu/HDF5/H5Image/ImageSpec.html
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IMunlink_palette( hid_t loc_id,
                          const char *image_name,
                          const char *pal_name )
{
    hid_t       did;
    hid_t       atid;
    hid_t       aid;
    H5T_class_t aclass;
    int         ok_pal, has_pal;

    /* check the arguments */
    if(image_name == NULL) 
      return -1;
    if(pal_name == NULL) 
      return -1;

    /* Try to find the palette dataset */
    has_pal = H5LTfind_dataset( loc_id, pal_name );

    /* It does not exist. Return */
    if ( has_pal == 0 )
        return -1;

    /* The image dataset may or not have the attribute "PALETTE"
    * First we try to open to see if it is already there; if not, it is created.
    * If it exists, the array of references is extended to hold the reference
    * to the new palette
    */

    /* First we get the image id */
    if((did = H5Dopen2(loc_id, image_name, H5P_DEFAULT)) < 0)
        return -1;

    /* Try to find the attribute "PALETTE" on the >>image<< dataset */
    ok_pal = H5LT_find_attribute(did, "PALETTE");

    /* It does not exist. Nothing to do */
    if(ok_pal == 0)
        return -1;

    /* The attribute exists, open it */
    else if(ok_pal ==  1)
    {
        if((aid = H5Aopen(did, "PALETTE", H5P_DEFAULT)) < 0)
            goto out;

        if((atid = H5Aget_type(aid)) < 0)
            goto out;

        if((aclass = H5Tget_class(atid)) < 0)
            goto out;

        /* Check if it is really a reference */
        if(aclass == H5T_REFERENCE)
        {
            /* Delete the attribute */
            if(H5Adelete(did, "PALETTE") < 0)
                goto out;

        }  /* H5T_REFERENCE */

        if(H5Tclose(atid) < 0)
            goto out;

        /* Close the attribute. */
        if(H5Aclose(aid) < 0)
            goto out;

    } /* ok_pal */

    /* Close the image dataset. */
    if(H5Dclose(did) < 0)
        return -1;

    return 0;

out:
    H5Dclose( did );
    return -1;
}


/*-------------------------------------------------------------------------
* Function: H5IMget_npalettes
*
* Purpose: Gets the number of palettes associated to an image
*
* Return: Success: 0, Failure: -1
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: July 22, 2001
*
* Comments:
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IMget_npalettes( hid_t loc_id,
                         const char *image_name,
                         hssize_t *npals )
{
    hid_t       did;
    hid_t       atid;
    hid_t       aid;
    hid_t       asid;
    H5T_class_t aclass;
    int         has_pal;

    /* check the arguments */
    if(image_name == NULL) 
      return -1;

    /*assume initially we have no palettes attached*/
    *npals = 0;

    /* Open the dataset. */
    if((did = H5Dopen2(loc_id, image_name, H5P_DEFAULT)) < 0)
        return -1;

    /* Try to find the attribute "PALETTE" on the >>image<< dataset */
    has_pal = H5IM_find_palette(did);

    if(has_pal ==  1 )
    {

        if((aid = H5Aopen(did, "PALETTE", H5P_DEFAULT)) < 0)
            goto out;

        if((atid = H5Aget_type(aid)) < 0)
            goto out;

        if((aclass = H5Tget_class(atid)) < 0)
            goto out;

        /* Check if it is really a reference */

        if(aclass == H5T_REFERENCE)
        {
            if((asid = H5Aget_space(aid)) < 0)
                goto out;

            *npals = H5Sget_simple_extent_npoints( asid );

            if ( H5Sclose( asid ) < 0)
                goto out;

        } /* H5T_REFERENCE */

        if ( H5Tclose( atid ) < 0)
            goto out;

        /* Close the attribute. */
        if ( H5Aclose( aid ) < 0)
            goto out;

    }

    /* Close the image dataset. */
    if ( H5Dclose( did ) < 0)
        return -1;

    return 0;

out:
    H5Dclose( did );
    return -1;

}


/*-------------------------------------------------------------------------
* Function: H5IMget_palette_info
*
* Purpose: Get palette information
*
* Return: Success: 0, Failure: -1
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: July 22, 2001
*
* Comments:
*  based on HDF5 Image and Palette Specification
*  http://hdf.ncsa.uiuc.edu/HDF5/H5Image/ImageSpec.html
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IMget_palette_info( hid_t loc_id,
                            const char *image_name,
                            int pal_number,
                            hsize_t *pal_dims )
{
    hid_t      did;
    int        has_pal;
    hid_t      atid=-1;
    hid_t      aid;
    hid_t      asid=-1;
    hssize_t   n_refs;
    hsize_t    dim_ref;
    hobj_ref_t *refbuf;     /* buffer to read references */
    hid_t      pal_id;
    hid_t      pal_space_id;
    hsize_t    pal_maxdims[2];

    /* check the arguments */
    if (image_name == NULL) 
      return -1;

    /* Open the dataset. */
    if((did = H5Dopen2(loc_id, image_name, H5P_DEFAULT)) < 0)
        return -1;

    /* Try to find the attribute "PALETTE" on the >>image<< dataset */
    has_pal = H5IM_find_palette(did);

    if(has_pal ==  1)
    {
        if((aid = H5Aopen(did, "PALETTE", H5P_DEFAULT)) < 0)
            goto out;

        if((atid = H5Aget_type(aid)) < 0)
            goto out;

        if(H5Tget_class(atid) < 0)
            goto out;

        /* Get the reference(s) */
        if((asid = H5Aget_space(aid)) < 0)
            goto out;

        n_refs = H5Sget_simple_extent_npoints(asid);

        dim_ref = (hsize_t)n_refs;

        refbuf = (hobj_ref_t*)HDmalloc( sizeof(hobj_ref_t) * (size_t)dim_ref );

        if ( H5Aread( aid, atid, refbuf ) < 0)
            goto out;

        /* Get the actual palette */
        if ( (pal_id = H5Rdereference2(did, H5P_DEFAULT, H5R_OBJECT, &refbuf[pal_number])) < 0)
            goto out;

        if ( (pal_space_id = H5Dget_space( pal_id )) < 0)
            goto out;

        if ( H5Sget_simple_extent_ndims( pal_space_id ) < 0)
            goto out;

        if ( H5Sget_simple_extent_dims( pal_space_id, pal_dims, pal_maxdims ) < 0)
            goto out;

        /* close */
        if (H5Dclose(pal_id)<0)
            goto out;
        if ( H5Sclose( pal_space_id ) < 0)
            goto out;
        if ( H5Sclose( asid ) < 0)
            goto out;
        if ( H5Tclose( atid ) < 0)
            goto out;
        if ( H5Aclose( aid ) < 0)
            goto out;
        HDfree( refbuf );


    }

    /* Close the image dataset. */
    if ( H5Dclose( did ) < 0)
        return -1;

    return 0;

out:
    H5Dclose( did );
    H5Sclose( asid );
    H5Tclose( atid );
    H5Aclose( aid );
    return -1;

}


/*-------------------------------------------------------------------------
* Function: H5IMget_palette
*
* Purpose: Read palette
*
* Return: Success: 0, Failure: -1
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: August 30, 2001
*
* Comments:
*  based on HDF5 Image and Palette Specification
*  http://hdf.ncsa.uiuc.edu/HDF5/H5Image/ImageSpec.html
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IMget_palette( hid_t loc_id,
                       const char *image_name,
                       int pal_number,
                       unsigned char *pal_data )
{
    hid_t      did;
    int        has_pal;
    hid_t      atid=-1;
    hid_t      aid;
    hid_t      asid=-1;
    hssize_t   n_refs;
    hsize_t    dim_ref;
    hobj_ref_t *refbuf;     /* buffer to read references */
    hid_t      pal_id;

    /* check the arguments */
    if (image_name == NULL) 
      return -1;
    if (pal_data == NULL) 
      return -1;


    /* Open the dataset. */
    if((did = H5Dopen2(loc_id, image_name, H5P_DEFAULT)) < 0)
        return -1;

    /* Try to find the attribute "PALETTE" on the >>image<< dataset */
    has_pal = H5IM_find_palette(did);

    if(has_pal ==  1 )
    {
        if((aid = H5Aopen(did, "PALETTE", H5P_DEFAULT)) < 0)
            goto out;

        if((atid = H5Aget_type(aid)) < 0)
            goto out;

        if(H5Tget_class(atid) < 0)
            goto out;

        /* Get the reference(s) */
        if((asid = H5Aget_space(aid)) < 0)
            goto out;

        n_refs = H5Sget_simple_extent_npoints(asid);

        dim_ref = (hsize_t)n_refs;

        refbuf = (hobj_ref_t*)HDmalloc( sizeof(hobj_ref_t) * (size_t)dim_ref );

        if ( H5Aread( aid, atid, refbuf ) < 0)
            goto out;

        /* Get the palette id */
        if ( (pal_id = H5Rdereference2(did, H5P_DEFAULT, H5R_OBJECT, &refbuf[pal_number])) < 0)
            goto out;

        /* Read the palette dataset */
        if ( H5Dread( pal_id, H5Dget_type(pal_id), H5S_ALL, H5S_ALL, H5P_DEFAULT, pal_data ) < 0)
            goto out;

        /* close */
        if (H5Dclose(pal_id)<0)
            goto out;
        if ( H5Sclose( asid ) < 0)
            goto out;
        if ( H5Tclose( atid ) < 0)
            goto out;
        if ( H5Aclose( aid ) < 0)
            goto out;
        HDfree( refbuf );
    }

    /* Close the image dataset. */
    if ( H5Dclose( did ) < 0)
        return -1;

    return 0;

out:
    H5Dclose( did );
    H5Sclose( asid );
    H5Tclose( atid );
    H5Aclose( aid );
    return -1;

}

/*-------------------------------------------------------------------------
* Function: H5IMis_image
*
* Purpose:
*
* Return: true, false, fail
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: August 30, 2001
*
* Comments:
*  based on HDF5 Image and Palette Specification
*  http://hdf.ncsa.uiuc.edu/HDF5/H5Image/ImageSpec.html
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IMis_image( hid_t loc_id,
                    const char *dset_name )
{
    hid_t      did;
    int        has_class;
    hid_t      atid;
    hid_t      aid = -1;
    char*      attr_data;    /* Name of attribute */
    hsize_t    storage_size; /* Size of storage for attribute */
    herr_t     ret;

    /* check the arguments */
    if (dset_name == NULL) 
      return -1;

    /* Assume initially fail condition */
    ret = -1;

    /* Open the dataset. */
    if((did = H5Dopen2(loc_id, dset_name, H5P_DEFAULT)) < 0)
        return -1;

    /* Try to find the attribute "CLASS" on the dataset */
    has_class = H5LT_find_attribute(did, "CLASS");

    if(has_class == 0)
    {
        H5Dclose(did);
        return 0;
    }
    else if(has_class ==  1)
    {

        if((aid = H5Aopen(did, "CLASS", H5P_DEFAULT)) < 0)
            goto out;

        if((atid = H5Aget_type(aid)) < 0)
            goto out;

	/* check to make sure attribute is a string */
	if(H5T_STRING != H5Tget_class(atid))
	    goto out;

	/* check to make sure string is null-terminated */
	if(H5T_STR_NULLTERM != H5Tget_strpad(atid))
	    goto out;

	/* allocate buffer large enough to hold string */
	if((storage_size = H5Aget_storage_size(aid)) == 0)
	    goto out;

	attr_data = (char*)HDmalloc( (size_t)storage_size * sizeof(char) + 1);
	if(attr_data == NULL)
	    goto out;

        if(H5Aread(aid, atid, attr_data) < 0)
            goto out;

        if(HDstrncmp(attr_data, IMAGE_CLASS, MIN(HDstrlen(IMAGE_CLASS),HDstrlen(attr_data))) == 0)
            ret = 1;
        else
            ret = 0;

	HDfree(attr_data);

        if ( H5Tclose( atid ) < 0)
            goto out;

        if ( H5Aclose( aid ) < 0)
            goto out;

    }

    /* Close the dataset. */
    if ( H5Dclose( did ) < 0)
        return -1;

    return ret;

out:
    H5Dclose( did );
    return -1;

}

/*-------------------------------------------------------------------------
* Function: H5IMis_palette
*
* Purpose:
*
* Return: true, false, fail
*
* Programmer: Pedro Vicente Nunes, pvn@ncsa.uiuc.edu
*
* Date: August 30, 2001
*
* Comments:
*  based on HDF5 Image and Palette Specification
*  http://hdf.ncsa.uiuc.edu/HDF5/H5Image/ImageSpec.html
*
* Modifications:
*
*-------------------------------------------------------------------------
*/

herr_t H5IMis_palette( hid_t loc_id,
                      const char *dset_name )
{
    hid_t      did;
    int        has_class;
    hid_t      atid;
    hid_t      aid = -1;
    char*      attr_data;    /* Name of attribute */
    hsize_t    storage_size; /* Size of storage for attribute */
    herr_t     ret;

    /* check the arguments */
    if (dset_name == NULL) 
      return -1;

    /* Assume initially fail condition */
    ret = -1;

    /* Open the dataset. */
    if((did = H5Dopen2(loc_id, dset_name, H5P_DEFAULT)) < 0)
        return -1;

    /* Try to find the attribute "CLASS" on the dataset */
    has_class = H5LT_find_attribute(did, "CLASS");

    if(has_class ==  0)
    {
        H5Dclose( did );
        return 0;
    }
    else if(has_class ==  1)
    {

        if((aid = H5Aopen(did, "CLASS", H5P_DEFAULT)) < 0)
            goto out;

        if((atid = H5Aget_type(aid)) < 0)
            goto out;

	/* check to make sure attribute is a string */
	if(H5T_STRING != H5Tget_class(atid))
	    goto out;

	/* check to make sure string is null-terminated */
	if(H5T_STR_NULLTERM != H5Tget_strpad(atid))
	    goto out;

	/* allocate buffer large enough to hold string */
	if((storage_size = H5Aget_storage_size(aid)) == 0)
	    goto out;

	attr_data = (char*)HDmalloc( (size_t)storage_size * sizeof(char) + 1);
	if(attr_data == NULL)
	    goto out;

        if(H5Aread(aid, atid, attr_data) < 0)
            goto out;

        if(HDstrncmp(attr_data, PALETTE_CLASS, MIN(HDstrlen(PALETTE_CLASS),HDstrlen(attr_data))) == 0)
            ret = 1;
        else
            ret = 0;

	HDfree(attr_data);

        if ( H5Tclose( atid ) < 0)
            goto out;

        if ( H5Aclose( aid ) < 0)
            goto out;

    }

    /* Close the dataset. */
    if ( H5Dclose( did ) < 0)
        return -1;

    return ret;

out:
    H5Dclose( did );
    return -1;

}

