cmjpghdr.c

Abstract—Wireless networks in combination with image sensors open up a multitude of previously unth

/*
 * Module:  cmJpgHdr
 *
 * Description:  Attach a jpeg header to jpeg data.
 *
 */
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>		/* data type type defs */
#include "cmJpgHdr.h"
#include "qtables.h"
#include "jpgHeader.h"
#include "cmApi.h"

extern Image_t g_defaultVideo;
extern Image_t g_defaultStill;

/*
 * global data   all of the following must be fixed up later
 */
long int m_qtd = 0;     /* offset in qtable to get ctable */
//long int m_width = 0;        /* width in pixels */
//long int m_height = 0;       /* height in pixels */
//long int m_width_still = 0;  /* width in pixels */
//long int m_height_still = 0; /* height in pixels */
/* W A R N I N G ---- The jpeg mode is set here but it really depends upon the
   settings in the VIDEO and STILL configuration registers.  In a future 
   revision, this information will be passed in as a parameter */
int jpeg_mode = 1;                      /* jpeg compression 0 = grey, 1 = 444, 2=422 */

/*
 * Function: cmJpgHdrBuild
 *
 * Inputs:
 *      jpeg_data       The buffer containing the 1670 jpeg data
 *      length          Number of bytes of data
 *      whole_jpg       The final destination buffer pointer
 *      whole_jpg_len   The pointer to the final length
 *      type            The API Image type (jpeg 444, 422 or GRAY)
 *      width           The width (X in pixels)
 *      height          The height (Y in pixels)
 *
 * Outputs:
 *      whole_jpg       Updated with the header plus the jpg data
 *      whole_jpg_len   Updated with the length of the jpg data with header
 *
 * Returns:  void (there is no way for it  to fail in this routine. Any failure is 
 *           catastrophic.)
 *
 */
void cmJpgHdrBuild(unsigned char *jpeg_data, int length, unsigned char *whole_jpg, int *whole_jpg_len, ImageType_t type, int width, int height)
{
    unsigned char Yqtable = jpeg_data[4];
    unsigned char Cqtable = Yqtable + (unsigned char)m_qtd;  // add qtable delta to Yqtable to get Cqtable

    unsigned char *Yqtable_ptr  = qtable_list[Yqtable];
    unsigned char *Cqtable_ptr  = qtable_list[Cqtable];

    int header_length;
    BYTE *header;

    if (type == CM_TYPE_JPEGGREY) {
        // grayscale

        // copy table to header
        memcpy(header_gray.QTABLE0 + 5, Yqtable_ptr, 64);

        // set image size in header
        //
        header_gray.SOF0[5] = (height >> 8) & 0xff;
        header_gray.SOF0[6] = (height) & 0xff;
        header_gray.SOF0[7] = (width >> 8) & 0xff;
        header_gray.SOF0[8] = (width) & 0xff;

        header = (UCHAR *) &header_gray;
        header_length = sizeof(header_gray);
    }
    else if (type == CM_TYPE_JPEG444) {
        // 444


        // copy tables to header
        memcpy(header_4xx.QTABLE0 + 5, Yqtable_ptr, 64);
        memcpy(header_4xx.QTABLE1 + 5, Cqtable_ptr, 64);
        memcpy(header_4xx.QTABLE2 + 5, Cqtable_ptr, 64);

        // set image size in header
        //
        header_4xx.SOF0[5] = (height >> 8) & 0xff;
        header_4xx.SOF0[6] = (height) & 0xff;
        header_4xx.SOF0[7] = (width >> 8) & 0xff;
        header_4xx.SOF0[8] = (width) & 0xff;

        header_4xx.SOF0[11] = 0x11;   // 444

        header = (UCHAR *) &header_4xx;
        header_length = sizeof(header_4xx);
    } else if (type == CM_TYPE_JPEG422) {
        // 422
        // copy tables to header
        memcpy(header_4xx.QTABLE0 + 5, Yqtable_ptr, 64);
        memcpy(header_4xx.QTABLE1 + 5, Cqtable_ptr, 64);
        memcpy(header_4xx.QTABLE2 + 5, Cqtable_ptr, 64);

        // set image size in header
        //
        header_4xx.SOF0[5] = (height >> 8) & 0xff;
        header_4xx.SOF0[6] = (height) & 0xff;
        header_4xx.SOF0[7] = (width >> 8) & 0xff;
        header_4xx.SOF0[8] = (width) & 0xff;

        header_4xx.SOF0[11] = 0x21;   // 422

        header = (UCHAR *) &header_4xx;
        header_length = sizeof(header_4xx);
    }
    else {
        return;
    }




    //length = length - 7;  // subtract leading 5 bytes & trailing status byte
    length = length - 5;  // subtract leading 5 bytes & trailing status byte


    // build image
    //

    memcpy(whole_jpg,header,header_length);
    memcpy(whole_jpg+header_length,jpeg_data+5,length);

	*whole_jpg_len = header_length + length;	/* global variable write */

}