about rotation of libva

[cherixy]

This project supports video-rotation according to reading the code. We can set the rotation-degree with attributiton of VADisplayAttribRotation, such of 90-degree,180-degree or 270-degree.
So I set this attributiton in my project to control real-video image. It doesn't work. I don't know where I make a mistake. Can you give me a tip? My testing code is listed as bellow:

...
/*************************************************************/
int i, num_display_attrs, max_display_attrs;
VADisplayAttribute *display_attrs = NULL;
/*************************************************************/

pstCtx->va_dpy = vaGetDisplay((void *)(&gx11_display));

va_status = vaInitialize(pstCtx->va_dpy, &major_ver, &minor_ver);
CHECK_VASTATUS(va_status, "vaInitialize");
/*****************************************************************/
max_display_attrs = vaMaxNumDisplayAttributes(pstCtx->va_dpy);
display_attrs = malloc(max_display_attrs * sizeof(display_attrs[0]));
if (!display_attrs)
{
printf("#########################max_display_attrs malloc failed\n");
free(display_attrs);
assert(0);
}

num_display_attrs = 0; /* XXX: workaround old GMA500 bug */
va_status = vaQueryDisplayAttributes(pstCtx->va_dpy, display_attrs, &num_display_attrs);
if (!vaapi_check_status(va_status, "vaQueryDisplayAttributes()"))
{
printf("#########################vaQueryDisplayAttributes\n");
free(display_attrs);
assert(0);
}

for (i = 0; i < num_display_attrs; i++) {
VADisplayAttribute * const display_attr = &display_attrs[i];
printf(" (%s/%s) min %d max %d value 0x%x\n",
(display_attr->flags & VA_DISPLAY_ATTRIB_GETTABLE) ? "get" : "---",
(display_attr->flags & VA_DISPLAY_ATTRIB_SETTABLE) ? "set" : "---",
display_attr->min_value,
display_attr->max_value,
display_attr->value);
}

VADisplayAttribute attr;
attr.type = VADisplayAttribRotation;
attr.value = VA_ROTATION_180;
attr.flags = VA_DISPLAY_ATTRIB_SETTABLE;
va_status = vaSetDisplayAttributes(pstCtx->va_dpy, &attr, 1);
if (!vaapi_check_status(va_status, "vaSetDisplayAttributes()"))
{
printf("###########################vaSetDisplayAttributes failed\n");
assert(0);
}
...