/**
 * draw_jpeg - Display a jpeg picture from (0, 0) on framebuffer
 * @name: picture name(foo.jpg)
 */
int draw_jpeg(char *name)
{
        struct jpeg_decompress_struct cinfo;
        struct jpeg_error_mgr jerr;
        FILE *infile;
        unsigned char  *buffer;
        int x, y;

unsigned char *tmp_buf;
        unsigned long size;
        int ret;

if ((infile = fopen(name, "rb")) == NULL) {
                fprintf(stderr, "open %s failed\n", name);
                return -1;
        }
        cinfo.err = jpeg_std_error(&jerr);
        jpeg_create_decompress(&cinfo);

// 获取图片文件大小
        fseek(infile, 0L, SEEK_END);
        size = ftell(infile);
        rewind(infile);
        
        tmp_buf = (unsigned char *)malloc(sizeof(char) * size);
        if (tmp_buf == NULL)
        {
                printf("malloc failed.\n");
                return -1;
        }
        ret = fread(tmp_buf, 1, size, infile);
        if (ret != size)
        {
                printf("read jpeg file error.\n");
                return -1;
        }
        // memory
        jpeg_mem_src(&cinfo, tmp_buf, size);        // 指定图片在内存的地址及大小

//jpeg_stdio_src(&cinfo, infile); // 指定图片文件
        
        jpeg_read_header(&cinfo, TRUE);
        jpeg_start_decompress(&cinfo);

if ((cinfo.output_width > fb_width) || (cinfo.output_height > fb_height)) {
                printf("too large JPEG file,cannot display\n");
                return -1;
        }
        buffer = (unsigned char *) malloc(cinfo.output_width * cinfo.output_components);
        //printf("%d %d\n", cinfo.output_width, cinfo.output_components); /*eg, 240 3(rgb888)*/
        x = y = 0;
        while (cinfo.output_scanline < cinfo.output_height) {
                jpeg_read_scanlines(&cinfo, &buffer, 1);
                if (fb_depth == 16) {
                        unsigned short  color;
                        for (x=0; x < cinfo.output_width; x++) {
                                // LCD为rgb565格式
                                color = make16color(buffer[x*3], buffer[x*3+1], buffer[x*3+2]);
                                fb_pixel(x, y, color);
                        }
                } else if (fb_depth == 24) {
                        // not test
                        memcpy((unsigned char *) fb_mem + y * fb_width * 3,
                                   buffer, cinfo.output_width * cinfo.output_components);
                }
                y++;        // next scanline
        }

jpeg_finish_decompress(&cinfo);
        jpeg_destroy_decompress(&cinfo);

fclose(infile);

free(tmp_buf);

free(buffer);
        return 0;
}