我见过许多指南，似乎总有一些缺失。
如果有人可以在这里发布一个完整的＆＃34;白痴＆＃34;指导它会很棒！
无论如何，我将在此提供我迄今为止尝试过的方法： 我试图下载 libjpeg ，并对所需的所有内容和makefile感到困惑。 我已下载 libjpeg-turbo ，目前我已将（成功）链接到jpeg.lib并包含＆＃34; jpeglib.h＆＃34;。
我使用的是我在网上找到的代码（在对它进行一些小的修改后导致它不能编译），这给了我运行时错误（＆＃34;缓冲区溢出）当块结束时（当最后一个＆＃39;}被调用时）已经发生了＃34;
void TestModel3D::write_JPEG_file(char * filename, int quality, int w, int h)
{
/* 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 %s\n", 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.client_data = (void*)&outfile;
cinfo.image_width = w; /* image width and height, in pixels */
cinfo.image_height = h;
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 = w * 3; /* JSAMPLEs per row in image_buffer */
const int BYTE_SIZE = (160 * 3);
UInt8 lineBuffer[BYTE_SIZE];
for (int y = 0; y < h; y++)
{
int j = 0;
for (int x=0; x < w; x++)
{
//printf("j: %d.\n", (x*3));
float r,g,b;
//if (CVFAILED(grabImage->GetPixel(x,y,r,g,b)))
//{
//printf("GetPixel Error!\n");
//}
//else
//{
lineBuffer[x * 3] = r;
lineBuffer[x * 3 + 1] = g;
lineBuffer[x * 3 + 2] = b;
//}
}
row_pointer[0] = & lineBuffer[0];
(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! */
}