Colony

#include <stdio.h>

#include "jpeglib.h"

#include <cv.h>

#include "memdst.h"

int write_JPEG_to_mem (unsigned char *storage, int length, IplImage *_img, int quality)

{

  struct jpeg_compress_struct cinfo;

  struct jpeg_error_mgr jerr;

  JSAMPROW row_pointer[1];

  int numBytes = -1; //size of jpeg after compression

  IplImage *img;

  img = cvCloneImage(_img);

  cvCvtColor(_img, img, CV_RGB2BGR);

  cinfo.err = jpeg_std_error(&jerr);

  jpeg_create_compress(&cinfo);

  jpeg_memory_dest(&cinfo,(JOCTET*)storage,length,&numBytes);

  cinfo.image_width = img->width;

  cinfo.image_height = img->height;

  cinfo.input_components = img->nChannels;

  cinfo.in_color_space = JCS_RGB;

  jpeg_set_defaults(&cinfo);

  jpeg_set_quality(&cinfo, quality, TRUE );

  jpeg_start_compress(&cinfo, TRUE);

  while (cinfo.next_scanline < cinfo.image_height) {

    row_pointer[0] = (unsigned char *)(img->imageData + cinfo.next_scanline * img->widthStep);

    (void) jpeg_write_scanlines(&cinfo, row_pointer, 1);

  }

  jpeg_finish_compress(&cinfo);

  jpeg_destroy_compress(&cinfo);

  cvReleaseImage(&img);

  return numBytes;

}