decoder: add support for video cropping.

Add gst_vaapi_picture_set_crop_rect() helper function to copy the video
cropping information from raw bitstreams to each picture being decoded.
Also add helper function to surface proxy to propagate that information
outside of libgstvaapi. e.g. plug-in elements or standalone applications.

Signed-off-by: Sreerenj Balachandran <sreerenj.balachandran@intel.com>
Signed-off-by: Gwenole Beauchesne <gwenole.beauchesne@intel.com>

gst-libs/gst/vaapi/gstvaapidecoder_objects.c

@@ -128,6 +128,11 @@ gst_vaapi_picture_create(
             }
             GST_VAAPI_PICTURE_FLAG_UNSET(picture, GST_VAAPI_PICTURE_FLAG_FF);
         }
+
+        if (parent_picture->has_crop_rect) {
+            picture->has_crop_rect = TRUE;
+            picture->crop_rect = parent_picture->crop_rect;
+        }
     }
     else {
         picture->type = GST_VAAPI_PICTURE_TYPE_NONE;
@@ -308,6 +313,10 @@ gst_vaapi_picture_output(GstVaapiPicture *picture)
         return FALSE;
 
     proxy = gst_vaapi_surface_proxy_ref(picture->proxy);
+
+    if (picture->has_crop_rect)
+        gst_vaapi_surface_proxy_set_crop_rect(proxy, &picture->crop_rect);
+
     gst_video_codec_frame_set_user_data(out_frame,
         proxy, (GDestroyNotify)gst_vaapi_mini_object_unref);
 
@@ -330,6 +339,17 @@ gst_vaapi_picture_output(GstVaapiPicture *picture)
     return TRUE;
 }
 
+void
+gst_vaapi_picture_set_crop_rect(GstVaapiPicture *picture,
+    const GstVaapiRectangle *crop_rect)
+{
+    g_return_if_fail(GST_VAAPI_IS_PICTURE(picture));
+
+    picture->has_crop_rect = crop_rect != NULL;
+    if (picture->has_crop_rect)
+        picture->crop_rect = *crop_rect;
+}
+
 /* ------------------------------------------------------------------------- */
 /* --- Slices                                                            --- */
 /* ------------------------------------------------------------------------- */

gst-libs/gst/vaapi/gstvaapidecoder_objects.h

@@ -131,6 +131,8 @@ struct _GstVaapiPicture {
     GstClockTime                pts;
     gint32                      poc;
     guint                       structure;
+    GstVaapiRectangle           crop_rect;
+    guint                       has_crop_rect   : 1;
 };
 
 G_GNUC_INTERNAL
@@ -166,6 +168,11 @@ G_GNUC_INTERNAL
 gboolean
 gst_vaapi_picture_output(GstVaapiPicture *picture);
 
+G_GNUC_INTERNAL
+void
+gst_vaapi_picture_set_crop_rect(GstVaapiPicture *picture,
+    const GstVaapiRectangle *crop_rect);
+
 static inline gpointer
 gst_vaapi_picture_ref(gpointer ptr)
 {

gst-libs/gst/vaapi/gstvaapisurfaceproxy.c

@@ -33,6 +33,27 @@
 #define DEBUG 1
 #include "gstvaapidebug.h"
 
+static void
+set_crop_rect_from_surface(GstVaapiSurfaceProxy *proxy)
+{
+    guint width, height;
+
+    gst_vaapi_surface_get_size(proxy->surface, &width, &height);
+    proxy->crop_rect.x = 0;
+    proxy->crop_rect.y = 0;
+    proxy->crop_rect.width = width;
+    proxy->crop_rect.height = height;
+}
+
+static inline void
+set_crop_rect(GstVaapiSurfaceProxy *proxy, const GstVaapiRectangle *crop_rect)
+{
+    if (crop_rect)
+        proxy->crop_rect = *crop_rect;
+    else
+        set_crop_rect_from_surface(proxy);
+}
+
 static void
 gst_vaapi_surface_proxy_finalize(GstVaapiSurfaceProxy *proxy)
 {
@@ -74,6 +95,8 @@ gst_vaapi_surface_proxy_new_from_pool(GstVaapiSurfacePool *pool)
     proxy->surface = gst_vaapi_video_pool_get_object(proxy->pool);
     if (!proxy->surface)
         goto error;
+    set_crop_rect_from_surface(proxy);
+
     proxy->timestamp = GST_CLOCK_TIME_NONE;
     proxy->duration = GST_CLOCK_TIME_NONE;
     proxy->destroy_func = NULL;
@@ -238,3 +261,37 @@ gst_vaapi_surface_proxy_set_destroy_notify(GstVaapiSurfaceProxy *proxy,
     proxy->destroy_func = destroy_func;
     proxy->destroy_data = user_data;
 }
+
+/**
+ * gst_vaapi_surface_proxy_get_crop_rect:
+ * @proxy: a #GstVaapiSurfaceProxy
+ *
+ * Returns the #GstVaapiRectangle stored in the @proxy and that
+ * represents the cropping rectangle for the underlying surface to be
+ * used for rendering.
+ *
+ * Return value: the #GstVaapiRectangle
+ */
+const GstVaapiRectangle *
+gst_vaapi_surface_proxy_get_crop_rect(GstVaapiSurfaceProxy *proxy)
+{
+    g_return_val_if_fail(proxy != NULL, NULL);
+
+    return GST_VAAPI_SURFACE_PROXY_CROP_RECT(proxy);
+}
+
+/**
+ * gst_vaapi_surface_proxy_set_crop_rect:
+ * @proxy: #GstVaapiSurfaceProxy
+ * @crop_rect: the #GstVaapiRectangle to be stored in @proxy
+ *
+ * Associates the @crop_rect with the @proxy
+ */
+void
+gst_vaapi_surface_proxy_set_crop_rect(GstVaapiSurfaceProxy *proxy,
+    const GstVaapiRectangle *crop_rect)
+{
+    g_return_if_fail(proxy != NULL);
+
+    set_crop_rect(proxy, crop_rect);
+}

gst-libs/gst/vaapi/gstvaapisurfaceproxy.h

@@ -117,6 +117,13 @@ void
 gst_vaapi_surface_proxy_set_destroy_notify(GstVaapiSurfaceProxy *proxy,
     GDestroyNotify destroy_func, gpointer user_data);
 
+const GstVaapiRectangle *
+gst_vaapi_surface_proxy_get_crop_rect(GstVaapiSurfaceProxy *proxy);
+
+void
+gst_vaapi_surface_proxy_set_crop_rect(GstVaapiSurfaceProxy *proxy,
+    const GstVaapiRectangle *crop_rect);
+
 G_END_DECLS
 
 #endif /* GST_VAAPI_SURFACE_PROXY_H */

gst-libs/gst/vaapi/gstvaapisurfaceproxy_priv.h

@@ -41,6 +41,7 @@ struct _GstVaapiSurfaceProxy {
     GstClockTime        duration;
     GDestroyNotify      destroy_func;
     gpointer            destroy_data;
+    GstVaapiRectangle   crop_rect;
 };
 
 #define GST_VAAPI_SURFACE_PROXY_FLAGS       GST_VAAPI_MINI_OBJECT_FLAGS
@@ -98,4 +99,16 @@ struct _GstVaapiSurfaceProxy {
 #define GST_VAAPI_SURFACE_PROXY_DURATION(proxy) \
     proxy->duration
 
+/**
+ * GST_VAAPI_SURFACE_PROXY_CROP_RECT:
+ * @proxy: a #GstVaapiSurfaceProxy
+ *
+ * Macro that evaluates to the video cropping rectangle of the underlying @proxy surface.
+ *
+ * This is an internal macro that does not do any run-time type check.
+ */
+#undef  GST_VAAPI_SURFACE_PROXY_CROP_RECT
+#define GST_VAAPI_SURFACE_PROXY_CROP_RECT(proxy) \
+    &(proxy)->crop_rect
+
 #endif /* GST_VAAPI_SURFACE_PROXY_PRIV_H */