C++通過jpeglib進行jpeg編碼，輸入格式為rgb、yuv422、yuv444

#include <stdio.h>
extern "C"{

include "../../src/jpeg_8c/jpeglib.h"
}
/*
brief jpeg編碼，輸入格式為uyvy/
void write_YUV_JPEG_file (char  filename, unsigned char yuvData, int quality,
                      int image_width,int image_height)
{

struct jpeg_compress_struct cinfo;

struct jpeg_error_mgr jerr;

FILE * outfile; /* target file */
//JSAMPROW row_pointer[1]; /* pointer to JSAMPLE row[s] */
//int row_stride; /* physical row width in image buffer */
JSAMPIMAGE buffer;

int band,i,buf_width[3],buf_height[3];
cinfo.err = jpeg_std_error(&jerr);

jpeg_create_compress(&cinfo);


if ((outfile = fopen(filename, "wb")) == NULL) {
    fprintf(stderr, "can't open %sn", filename);
    exit(1);
}
jpeg_stdio_dest(&cinfo, outfile);


cinfo.image_width = image_width; /* image width and height, in pixels */
cinfo.image_height = image_height;
cinfo.input_components = 3; /* # of color components per pixel */
cinfo.in_color_space = JCS_YCbCr; /* colorspace of input image */

jpeg_set_defaults(&cinfo);

jpeg_set_quality(&cinfo, quality, TRUE );

//////////////////////////////
cinfo.raw_data_in = TRUE;
cinfo.jpeg_color_space = JCS_YCbCr;
cinfo.comp_info[0].h_samp_factor = 2;
cinfo.comp_info[0].v_samp_factor = 1;
/////////////////////////

jpeg_start_compress(&cinfo, TRUE);

buffer = (JSAMPIMAGE) (*cinfo.mem->alloc_small) ((j_common_ptr) &cinfo, 
    JPOOL_IMAGE, 3 * sizeof(JSAMPARRAY));  
for(band=0; band<3; band++)
{
    buf_width[band] = cinfo.comp_info[band].width_in_blocks * DCTSIZE;
    buf_height[band] = cinfo.comp_info[band].v_samp_factor * DCTSIZE;
    buffer[band] = (*cinfo.mem->alloc_sarray) ((j_common_ptr) &cinfo,
        JPOOL_IMAGE, buf_width[band], buf_height[band]);
}  

unsigned char *rawData[3];
rawData[0]=yuvData;
rawData[1]=yuvData+image_width*image_height;
rawData[2]=yuvData+image_width*image_height*3/2;

int max_line = cinfo.max_v_samp_factor*DCTSIZE;  
for(int counter=0; cinfo.next_scanline < cinfo.image_height; counter++)
{  
    //buffer image copy.
    for(band=0; band<3; band++)
    {
        int mem_size = buf_width[band];
        unsigned char *pDst = (unsigned char *) buffer[band][0];
        unsigned char *pSrc = (unsigned char *) (rawData[band] + //yuv.data[band]分別表示YUV起始地址
            counter*buf_height[band] * buf_width[band]);

        for(i=0; i<buf_height[band]; i++)
        {
            memcpy(pDst, pSrc, mem_size);
            pSrc += buf_width[band];
            pDst += buf_width[band];
        }
    }
    jpeg_write_raw_data(&cinfo, buffer, max_line);
}


jpeg_finish_compress(&cinfo);

fclose(outfile);

jpeg_destroy_compress(&cinfo);



}
/*
brief jpeg編碼，輸入格式為rgb/
void write_RGB_JPEG_file(char  filename, unsigned char rgb,int image_width,
                         int image_height, int quality /= 90/)
{
    JSAMPLE  image_buffer = (JSAMPLE)rgb;
    /* This struct contains the JPEG compression parameters and pointers to

* working space (which is allocated as needed by the JPEG library).
* It is possible to have several such structures, representing multiple
* compression/decompression processes, in existence at once.  We refer
* to any one struct (and its associated working data) as a "JPEG object".
*/
struct jpeg_compress_struct cinfo;
/* This struct represents a JPEG error handler.  It is declared separately
* because applications often want to supply a specialized error handler
* (see the second half of this file for an example).  But here we just
* take the easy way out and use the standard error handler, which will
* print a message on stderr and call exit() if compression fails.
* Note that this struct must live as long as the main JPEG parameter
* struct, to avoid dangling-pointer problems.
*/
struct jpeg_error_mgr jerr;
/* More stuff */
FILE * outfile;     /* target file */
JSAMPROW row_pointer[1];    /* pointer to JSAMPLE row[s] */
int row_stride;     /* physical row width in image buffer */

/* Step 1: allocate and initialize JPEG compression object */

/* We have to set up the error handler first, in case the initialization
* step fails.  (Unlikely, but it could happen if you are out of memory.)
* This routine fills in the contents of struct jerr, and returns jerr's
* address which we place into the link field in cinfo.
*/
cinfo.err = jpeg_std_error(&jerr);
/* Now we can initialize the JPEG compression object. */
jpeg_create_compress(&cinfo);

/* Step 2: specify data destination (eg, a file) */
/* Note: steps 2 and 3 can be done in either order. */

/* Here we use the library-supplied code to send compressed data to a
* stdio stream.  You can also write your own code to do something else.
* VERY IMPORTANT: use "b" option to fopen() if you are on a machine that
* requires it in order to write binary files.
*/
if ((outfile = fopen(filename, "wb")) == NULL) {
    fprintf(stderr, "can't open %sn", filename);
    exit(1);
}
jpeg_stdio_dest(&cinfo, outfile);

/* Step 3: set parameters for compression */

/* First we supply a description of the input image.
* Four fields of the cinfo struct must be filled in:
*/
cinfo.image_width = image_width;    /* image width and height, in pixels */
cinfo.image_height = image_height;
cinfo.input_components = 3;     /* # of color components per pixel */
cinfo.in_color_space = JCS_RGB;     /* colorspace of input image */
/* Now use the library's routine to set default compression parameters.
* (You must set at least cinfo.in_color_space before calling this,
* since the defaults depend on the source color space.)
*/
jpeg_set_defaults(&cinfo);
/* Now you can set any non-default parameters you wish to.
* Here we just illustrate the use of quality (quantization table) scaling:
*/
jpeg_set_quality(&cinfo, quality, TRUE /* limit to baseline-JPEG values */);

/* Step 4: Start compressor */

/* TRUE ensures that we will write a complete interchange-JPEG file.
* Pass TRUE unless you are very sure of what you're doing.
*/
jpeg_start_compress(&cinfo, TRUE);

/* Step 5: while (scan lines remain to be written) */
/*           jpeg_write_scanlines(...); */

/* Here we use the library's state variable cinfo.next_scanline as the
* loop counter, so that we don't have to keep track ourselves.
* To keep things simple, we pass one scanline per call; you can pass
* more if you wish, though.
*/
row_stride = image_width * 3;   /* JSAMPLEs per row in image_buffer */

while (cinfo.next_scanline < cinfo.image_height) {
    /* jpeg_write_scanlines expects an array of pointers to scanlines.
    * Here the array is only one element long, but you could pass
    * more than one scanline at a time if that's more convenient.
    */
    row_pointer[0] = & image_buffer[cinfo.next_scanline * row_stride];
    (void) jpeg_write_scanlines(&cinfo, row_pointer, 1);
}

/* Step 6: Finish compression */

jpeg_finish_compress(&cinfo);
/* After finish_compress, we can close the output file. */
fclose(outfile);

/* Step 7: release JPEG compression object */

/* This is an important step since it will release a good deal of memory. */
jpeg_destroy_compress(&cinfo);

/* And we're done! */

}
/*
brief jpeg編碼，輸入格式為yuv444/
void write_YUV444_JPEG_file(char  filename, unsigned char yuv444,int image_width,
                         int image_height, int quality /= 90/)
{
    JSAMPLE  image_buffer = (JSAMPLE)yuv444;
    /* This struct contains the JPEG compression parameters and pointers to

* working space (which is allocated as needed by the JPEG library).
* It is possible to have several such structures, representing multiple
* compression/decompression processes, in existence at once.  We refer
* to any one struct (and its associated working data) as a "JPEG object".
*/
struct jpeg_compress_struct cinfo;
/* This struct represents a JPEG error handler.  It is declared separately
* because applications often want to supply a specialized error handler
* (see the second half of this file for an example).  But here we just
* take the easy way out and use the standard error handler, which will
* print a message on stderr and call exit() if compression fails.
* Note that this struct must live as long as the main JPEG parameter
* struct, to avoid dangling-pointer problems.
*/
struct jpeg_error_mgr jerr;
/* More stuff */
FILE * outfile;     /* target file */
JSAMPROW row_pointer[1];    /* pointer to JSAMPLE row[s] */
int row_stride;     /* physical row width in image buffer */

/* Step 1: allocate and initialize JPEG compression object */

/* We have to set up the error handler first, in case the initialization
* step fails.  (Unlikely, but it could happen if you are out of memory.)
* This routine fills in the contents of struct jerr, and returns jerr's
* address which we place into the link field in cinfo.
*/
cinfo.err = jpeg_std_error(&jerr);
/* Now we can initialize the JPEG compression object. */
jpeg_create_compress(&cinfo);

/* Step 2: specify data destination (eg, a file) */
/* Note: steps 2 and 3 can be done in either order. */

/* Here we use the library-supplied code to send compressed data to a
* stdio stream.  You can also write your own code to do something else.
* VERY IMPORTANT: use "b" option to fopen() if you are on a machine that
* requires it in order to write binary files.
*/
if ((outfile = fopen(filename, "wb")) == NULL) {
    fprintf(stderr, "can't open %sn", filename);
    exit(1);
}
jpeg_stdio_dest(&cinfo, outfile);

/* Step 3: set parameters for compression */

/* First we supply a description of the input image.
* Four fields of the cinfo struct must be filled in:
*/
cinfo.image_width = image_width;    /* image width and height, in pixels */
cinfo.image_height = image_height;
cinfo.input_components = 3;     /* # of color components per pixel */
cinfo.in_color_space = JCS_YCbCr;   /* colorspace of input image */
/* Now use the library's routine to set default compression parameters.
* (You must set at least cinfo.in_color_space before calling this,
* since the defaults depend on the source color space.)
*/
jpeg_set_defaults(&cinfo);
/* Now you can set any non-default parameters you wish to.
* Here we just illustrate the use of quality (quantization table) scaling:
*/
jpeg_set_quality(&cinfo, quality, TRUE /* limit to baseline-JPEG values */);

/* Step 4: Start compressor */

/* TRUE ensures that we will write a complete interchange-JPEG file.
* Pass TRUE unless you are very sure of what you're doing.
*/
jpeg_start_compress(&cinfo, TRUE);

/* Step 5: while (scan lines remain to be written) */
/*           jpeg_write_scanlines(...); */

/* Here we use the library's state variable cinfo.next_scanline as the
* loop counter, so that we don't have to keep track ourselves.
* To keep things simple, we pass one scanline per call; you can pass
* more if you wish, though.
*/
row_stride = image_width * 3;   /* JSAMPLEs per row in image_buffer */

while (cinfo.next_scanline < cinfo.image_height) {
    /* jpeg_write_scanlines expects an array of pointers to scanlines.
    * Here the array is only one element long, but you could pass
    * more than one scanline at a time if that's more convenient.
    */
    row_pointer[0] = & image_buffer[cinfo.next_scanline * row_stride];
    (void) jpeg_write_scanlines(&cinfo, row_pointer, 1);
}

/* Step 6: Finish compression */

jpeg_finish_compress(&cinfo);
/* After finish_compress, we can close the output file. */
fclose(outfile);

/* Step 7: release JPEG compression object */

/* This is an important step since it will release a good deal of memory. */
jpeg_destroy_compress(&cinfo);

/* And we're done! */

}</pre>