enc_jpeg2000.c

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#ifndef USE_JPEG2000
void dummy(void) {}
#else   /* USE_JPEG2000 */
 
#include <stdio.h>
#include <stdlib.h>
#include "grib2.h"
#include "jasper/jasper.h"
#define JAS_1_700_2 
#define MAXOPTSSIZE 1024 
int
enc_jpeg2000(unsigned char *cin, g2int width, g2int height, g2int nbits,
             g2int ltype, g2int ratio, g2int retry, char *outjpc,
             g2int jpclen)
{
    int ier, rwcnt;
    jas_image_t image;
    jas_stream_t *jpcstream, *istream;
    jas_image_cmpt_t cmpt, *pcmpt;
    char opts[MAXOPTSSIZE];
 
    /* Set lossy compression options, if requested. */
    if (ltype != 1)
        opts[0] = (char)0;
    else 
        snprintf(opts,MAXOPTSSIZE,"mode=real\nrate=%f",1.0/(float)ratio);
 
    if (retry == 1)  /* option to increase number of guard bits */
        strcat(opts,"\nnumgbits=4");
 
    /* Initialize the JasPer image structure describing the grayscale
     * image to encode into the JPEG2000 code stream. */
    image.tlx_ = 0;
    image.tly_ = 0;
#ifdef JAS_1_500_4
    image.brx_ = (uint_fast32_t)width;
    image.bry_ = (uint_fast32_t)height;
#endif
#ifdef JAS_1_700_2
    image.brx_ = (jas_image_coord_t)width;
    image.bry_ = (jas_image_coord_t)height;
#endif
    image.numcmpts_ = 1;
    image.maxcmpts_ = 1;
#ifdef JAS_1_500_4
    image.colormodel_ = JAS_IMAGE_CM_GRAY;         /* grayscale Image */
#endif
#ifdef JAS_1_700_2
    image.clrspc_ = JAS_CLRSPC_SGRAY;         /* grayscale Image */
    image.cmprof_ = 0;
#endif
 
    cmpt.tlx_ = 0;
    cmpt.tly_ = 0;
    cmpt.hstep_ = 1;
    cmpt.vstep_ = 1;
#ifdef JAS_1_500_4
    cmpt.width_ = (uint_fast32_t)width;
    cmpt.height_ = (uint_fast32_t)height;
#endif
#ifdef JAS_1_700_2
    cmpt.width_ = (jas_image_coord_t)width;
    cmpt.height_ = (jas_image_coord_t)height;
    cmpt.type_ = JAS_IMAGE_CT_COLOR(JAS_CLRSPC_CHANIND_GRAY_Y);
#endif
    cmpt.prec_ = nbits;
    cmpt.sgnd_ = 0;
    cmpt.cps_ = (nbits + 7) / 8;
 
    pcmpt = &cmpt;
    image.cmpts_ = &pcmpt;
 
    /* Open a JasPer stream containing the input grayscale values. */
    istream = jas_stream_memopen((char *)cin, height * width * cmpt.cps_);
    cmpt.stream_ = istream;
 
    /* Open an output stream that will contain the encoded jpeg2000
     * code stream. */
    jpcstream = jas_stream_memopen(outjpc, (int)jpclen);
 
    /* Encode image. */
    if ((ier = jpc_encode(&image, jpcstream, opts)))
    {
        printf(" jpc_encode return = %d \n",ier);
        return -3;
    }
 
    /* Clean up JasPer work structures. */
    rwcnt = jpcstream->rwcnt_;
    ier = jas_stream_close(istream);
    ier = jas_stream_close(jpcstream);
 
    /* Return size of jpeg2000 code stream. */
    return (rwcnt);
}
 
#endif   /* USE_JPEG2000 */