image: add helpers to extract pixels to user buffers.

docs/reference/libs/libs-sections.txt

@@ -307,6 +307,8 @@ gst_vaapi_image_get_plane_count
 gst_vaapi_image_get_plane
 gst_vaapi_image_get_pitch
 gst_vaapi_image_get_data_size
+gst_vaapi_image_get_buffer
+gst_vaapi_image_get_raw
 gst_vaapi_image_update_from_buffer
 <SUBSECTION Standard>
 GST_VAAPI_IMAGE

gst-libs/gst/vaapi/gstvaapiimage.c

@@ -1137,6 +1137,90 @@ copy_image(
     return TRUE;
 }
 
+/**
+ * gst_vaapi_image_get_buffer:
+ * @image: a #GstVaapiImage
+ * @buffer: a #GstBuffer
+ * @rect: a #GstVaapiRectangle expressing a region, or %NULL for the
+ *   whole image
+ *
+ * Transfers pixels data contained in the @image into the #GstBuffer.
+ * Both image structures shall have the same format.
+ *
+ * Return value: %TRUE on success
+ */
+gboolean
+gst_vaapi_image_get_buffer(
+    GstVaapiImage     *image,
+    GstBuffer         *buffer,
+    GstVaapiRectangle *rect
+)
+{
+    GstVaapiImagePrivate *priv;
+    GstVaapiImageRaw dst_image, src_image;
+    gboolean success;
+
+    g_return_val_if_fail(GST_VAAPI_IS_IMAGE(image), FALSE);
+    g_return_val_if_fail(image->priv->is_constructed, FALSE);
+    g_return_val_if_fail(GST_IS_BUFFER(buffer), FALSE);
+
+    priv = image->priv;
+
+    if (!init_image_from_buffer(&dst_image, buffer))
+        return FALSE;
+    if (dst_image.format != priv->format)
+        return FALSE;
+    if (dst_image.width != priv->width || dst_image.height != priv->height)
+        return FALSE;
+
+    if (!_gst_vaapi_image_map(image, &src_image))
+        return FALSE;
+
+    success = copy_image(&dst_image, &src_image, rect);
+
+    if (!_gst_vaapi_image_unmap(image))
+        return FALSE;
+
+    return success;
+}
+
+/**
+ * gst_vaapi_image_get_raw:
+ * @image: a #GstVaapiImage
+ * @dst_image: a #GstVaapiImageRaw
+ * @buffer: a #GstBuffer
+ * @rect: a #GstVaapiRectangle expressing a region, or %NULL for the
+ *   whole image
+ *
+ * Transfers pixels data contained in the @image into the #GstVaapiImageRaw.
+ * Both image structures shall have the same format.
+ *
+ * Return value: %TRUE on success
+ */
+gboolean
+gst_vaapi_image_get_raw(
+    GstVaapiImage     *image,
+    GstVaapiImageRaw  *dst_image,
+    GstVaapiRectangle *rect
+)
+{
+    GstVaapiImageRaw src_image;
+    gboolean success;
+
+    g_return_val_if_fail(GST_VAAPI_IS_IMAGE(image), FALSE);
+    g_return_val_if_fail(image->priv->is_constructed, FALSE);
+
+    if (!_gst_vaapi_image_map(image, &src_image))
+        return FALSE;
+
+    success = copy_image(dst_image, &src_image, rect);
+
+    if (!_gst_vaapi_image_unmap(image))
+        return FALSE;
+
+    return success;
+}
+
 /**
  * gst_vaapi_image_update_from_buffer:
  * @image: a #GstVaapiImage

gst-libs/gst/vaapi/gstvaapiimage.h

@@ -175,6 +175,20 @@ gst_vaapi_image_get_pitch(GstVaapiImage *image, guint plane);
 guint
 gst_vaapi_image_get_data_size(GstVaapiImage *image);
 
+gboolean
+gst_vaapi_image_get_buffer(
+    GstVaapiImage     *image,
+    GstBuffer         *buffer,
+    GstVaapiRectangle *rect
+);
+
+gboolean
+gst_vaapi_image_get_raw(
+    GstVaapiImage     *image,
+    GstVaapiImageRaw  *dst_image,
+    GstVaapiRectangle *rect
+);
+
 gboolean
 gst_vaapi_image_update_from_buffer(
     GstVaapiImage     *image,