enc_jpeg2000.c

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#include <stdio.h>
#include <stdlib.h>
#include "grib2_int.h"
#include "jasper/jasper.h"
 
#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];
    int fmt;
 
    /* 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;
    image.brx_ = (jas_image_coord_t)width;
    image.bry_ = (jas_image_coord_t)height;
    image.numcmpts_ = 1;
    image.maxcmpts_ = 1;
    image.clrspc_ = JAS_CLRSPC_SGRAY;         /* grayscale Image */
    image.cmprof_ = 0;
 
    cmpt.tlx_ = 0;
    cmpt.tly_ = 0;
    cmpt.hstep_ = 1;
    cmpt.vstep_ = 1;
    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);
    cmpt.prec_ = nbits;
    cmpt.sgnd_ = 0;
    cmpt.cps_ = (nbits + 7) / 8;
 
    pcmpt = &cmpt;
    image.cmpts_ = &pcmpt;
 
    /* Initialize Jasper. */
#ifdef JASPER3
    jas_conf_clear();
    /* static jas_std_allocator_t allocator; */
    /* jas_std_allocator_init(&allocator); */
    /* jas_conf_set_allocator(JAS_CAST(jas_std_allocator_t *, &allocator)); */
    jas_conf_set_max_mem_usage(10000000);
    jas_conf_set_multithread(true);
    if (jas_init_library())
        return G2_JASPER_INIT;
    if (jas_init_thread())
        return G2_JASPER_INIT;
#else
    if (jas_init())
        return G2_JASPER_INIT;
#endif /* JASPER3 */
 
    /* 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);
 
    /* Get jasper ID of JPEG encoder. */
    fmt = jas_image_strtofmt(G2C_JASPER_JPEG_FORMAT_NAME);
 
    /* Encode image. */
    if ((ier = jas_image_encode(&image, jpcstream, fmt, opts)))
        return G2_JASPER_ENCODE;
 
    /* Rememeber the length in bytes of the encoded JPEG code
     * stream. */
    rwcnt = jpcstream->rwcnt_;
 
    /* Clean up JasPer work structures. */
    ier = jas_stream_close(istream);
    ier = jas_stream_close(jpcstream);
 
    /* Finalize jasper. */
#ifdef JASPER3
    jas_cleanup_thread();
    jas_cleanup_library();
#else
    jas_cleanup();
#endif /* JASPER3 */
 
    /* Return size of jpeg2000 code stream. */
    return rwcnt;
}