如何使用jpeglib库压缩yuv422？
如题：
我是yuv422 yuyv这样的格式，然后我将它转换成了平面格式，即先是Y，后是U，再是V，这样排列。使用的函数如下，该函数是在网上搜的，但是运行出现错误，不知是yuv的输入参数错误（不知他是怎么排的），还是本来这个函数就有问题，请大侠们帮忙看看：
int yuv422_to_jpeg(unsigned char *data, int image_width, int image_height, char *filename, int
quality)
{
struct jpeg_compress_struct cinfo;
struct jpeg_error_mgr jerr;
//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], mem_size, max_line, counter;
unsigned char *yuv[3];
/*uint8_t*/unsigned char *pSrc, *pDst;
FILE * outfile; /* target file */
yuv[0] = data;
yuv[1] = yuv[0] + (image_width * image_height);
yuv[2] = yuv[1] + (image_width * image_height) /2;
if ((outfile = fopen(filename, "wb")) == NULL) {
fprintf(stderr, "can't open %s\n", filename);
exit(1);
}
cinfo.err = jpeg_std_error(&jerr);
jpeg_create_compress(&cinfo);
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_RGB; /* colorspace of input image */
jpeg_set_defaults(&cinfo);
jpeg_set_quality(&cinfo, quality, TRUE );
cinfo.raw_data_in = TRUE;
cinfo.do_fancy_downsampling=FALSE;
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]);
}
max_line = cinfo.max_v_samp_factor*DCTSIZE;
for(counter=0; cinfo.next_scanline < cinfo.image_height; counter++)
{
//buffer image copy.
for(band=0; band <3; band++)
{
mem_size = buf_width[band];
pDst = (unsigned char *) buffer[band][0];
pSrc = (unsigned char *) yuv[band] + counter*buf_height[band] *
buf_width[band];
for(i=0; i <buf_height[band]; i++)
{
memcpy(pDst, pSrc, mem_size);//拷贝一
行
pSrc += buf_width[band];
pDst += buf_width[band];
}
}
jpeg_write_raw_data(&cinfo, buffer, max_line);//写一行
}
jpeg_finish_compress(&cinfo);
fclose(outfile);
jpeg_destroy_compress(&cinfo);
return 0;
}
跟踪发现：
buf_width[0]=1632，而我的图像的分辨率是1628*1236
同时：
for(counter=0; cinfo.next_scanline < cinfo.image_height; counter++)
{
//buffer image copy.
for(band=0; band <3; band++)
{
mem_size = buf_width[band];
pDst = (unsigned char *) buffer[band][0];
pSrc = (unsigned char *) yuv[band] + counter*buf_height[band] *
buf_width[band];
for(i=0; i <buf_height[band]; i++)
{
memcpy(pDst, pSrc, mem_size);//拷贝一
行
pSrc += buf_width[band];
pDst += buf_width[band];
}
}
jpeg_write_raw_data(&cinfo, buffer, max_line);//写一行
}
这个地方当
counter=154时，就发生内存错误了，因为后面还有一个循环，154*8=1232，这样在进行memcpy时，内存错误，
不知道大家是怎么讲Yuv422 转换到jpg的，谢谢！
[解决办法]
找到了以前用过的一段程序，是可以正常工作的，你可以参考下
[code=C/C++][/code]/**
\brief jpeg编码，输入格式为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 %s\n", 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]分别表示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);
}
