jpeg内存转bmp文件

linux下如下编译： yang@yang-X230:~/work4c/jpg2bmp-mem$ gcc -c rgbgray2bmpgray.c -o rgbgraybmpgray.o yang@yang-X230:~/work4c/jpg2bmp-mem$ gcc -c jpeg2rgb.c -o jpeg2rgb.o yang@yang-X230:~/work4c/jpg2bmp-mem$ gcc -c v4l2main-bmp.c -o v4l2main.o yang@yang-X230:~/work4c/jpg2bmp-mem$ gcc v4l2main.o jpeg2rgb.o rgbgraybmpgray.o -o v4l2main -ljpeg -L /usr/lib/x86_64-linux-gnu/