Linux LCD 显示JPG图片问题
这几天在学习LCD,移植号LCD 驱动后想在上边显示图片,
硬件环境TQ2440
参考 http://blog.chinaunix.net/uid-25120309-id-3794265.html 这个文章,我的文件是LCD.C
但是使用arm-linux-gcc 编译的时候报错
LCD.C:(.text+0x384): undefined reference to `jpeg_std_error(jpeg_error_mgr*)'
LCD.C:(.text+0x3a0): undefined reference to `jpeg_CreateDecompress(jpeg_decompress_struct*, int, unsigned int)'
LCD.C:(.text+0x3b0): undefined reference to `jpeg_stdio_src(jpeg_decompress_struct*, _IO_FILE*)'
LCD.C:(.text+0x3c0): undefined reference to `jpeg_read_header(jpeg_decompress_struct*, int)'
LCD.C:(.text+0x3cc): undefined reference to `jpeg_start_decompress(jpeg_decompress_struct*)'
LCD.C:(.text+0x410): undefined reference to `jpeg_read_scanlines(jpeg_decompress_struct*, unsigned char**, unsigned int)'
LCD.C:(.text+0x59c): undefined reference to `jpeg_finish_decompress(jpeg_decompress_struct*)'
LCD.C:(.text+0x5a8): undefined reference to `jpeg_destroy_decompress(jpeg_decompress_struct*)'
collect2: ld returned 1 exit status
应该是jpg编解码库的问题,参考
http://blog.sina.com.cn/s/blog_7956a73c0100wj9s.html
在Ubuntu下安装了libjepg,
但是还是不行,
参考 http://blog.sina.com.cn/s/blog_67e1c5cc0100ydgb.html
说要
用gcc编译的动态库要在g++中使用的话,在包含头文件时要使用extern "C".
如:
extern "C" {
#include <jpeglib.h>
}
但是这个怎么包含呢? 在哪个文件里? ,我的文件是LCD.C,在LCD.C里已经包含了#include <jpeglib.h>