/*
 *  gstvaapivideomemory.c - Gstreamer/VA video memory
 *
 *  Copyright (C) 2013 Intel Corporation
 *    Author: Gwenole Beauchesne <gwenole.beauchesne@intel.com>
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public License
 *  as published by the Free Software Foundation; either version 2.1
 *  of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free
 *  Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 *  Boston, MA 02110-1301 USA
 */

#include "gst/vaapi/sysdeps.h"
#include <gst/vaapi/gstvaapisurfacepool.h>
#include <gst/vaapi/gstvaapiimagepool.h>
#include "gstvaapivideomemory.h"

GST_DEBUG_CATEGORY_STATIC (gst_debug_vaapivideomemory);
#define GST_CAT_DEFAULT gst_debug_vaapivideomemory

#ifndef GST_VIDEO_INFO_FORMAT_STRING
#define GST_VIDEO_INFO_FORMAT_STRING(vip) \
  gst_video_format_to_string (GST_VIDEO_INFO_FORMAT (vip))
#endif

/* Defined if native VA surface formats are preferred over direct rendering */
#define USE_NATIVE_FORMATS 1

/* ------------------------------------------------------------------------ */
/* --- GstVaapiVideoMemory                                              --- */
/* ------------------------------------------------------------------------ */

static void
gst_vaapi_video_memory_reset_image (GstVaapiVideoMemory * mem);

static guchar *
get_image_data (GstVaapiImage * image)
{
  guchar *data;
  VAImage va_image;

  data = gst_vaapi_image_get_plane (image, 0);
  if (!data || !gst_vaapi_image_get_image (image, &va_image))
    return NULL;

  data -= va_image.offsets[0];
  return data;
}

static GstVaapiImage *
new_image (GstVaapiDisplay * display, const GstVideoInfo * vip)
{
  return gst_vaapi_image_new (display, GST_VIDEO_INFO_FORMAT (vip),
      GST_VIDEO_INFO_WIDTH (vip), GST_VIDEO_INFO_HEIGHT (vip));
}

static gboolean
ensure_image (GstVaapiVideoMemory * mem)
{
  if (!mem->image && mem->use_direct_rendering) {
    mem->image = gst_vaapi_surface_derive_image (mem->surface);
    if (!mem->image) {
      GST_WARNING ("failed to derive image, fallbacking to copy");
      mem->use_direct_rendering = FALSE;
    } else if (gst_vaapi_surface_get_format (mem->surface) !=
        GST_VIDEO_INFO_FORMAT (mem->image_info)) {
      gst_vaapi_object_replace (&mem->image, NULL);
      mem->use_direct_rendering = FALSE;
    }
  }

  if (!mem->image) {
    GstVaapiVideoAllocator *const allocator =
        GST_VAAPI_VIDEO_ALLOCATOR_CAST (GST_MEMORY_CAST (mem)->allocator);

    mem->image = gst_vaapi_video_pool_get_object (allocator->image_pool);
    if (!mem->image)
      return FALSE;
  }
  gst_vaapi_video_meta_set_image (mem->meta, mem->image);
  return TRUE;
}

static GstVaapiSurface *
new_surface (GstVaapiDisplay * display, const GstVideoInfo * vip)
{
  GstVaapiSurface *surface;
  GstVaapiChromaType chroma_type;

  /* Try with explicit format first */
  if (!USE_NATIVE_FORMATS &&
      GST_VIDEO_INFO_FORMAT (vip) != GST_VIDEO_FORMAT_ENCODED) {
    surface = gst_vaapi_surface_new_with_format (display,
        GST_VIDEO_INFO_FORMAT (vip), GST_VIDEO_INFO_WIDTH (vip),
        GST_VIDEO_INFO_HEIGHT (vip));
    if (surface)
      return surface;
  }

  /* Try to pick something compatible, i.e. with same chroma type */
  chroma_type =
      gst_vaapi_video_format_get_chroma_type (GST_VIDEO_INFO_FORMAT (vip));
  if (!chroma_type)
    return NULL;
  return gst_vaapi_surface_new (display, chroma_type,
      GST_VIDEO_INFO_WIDTH (vip), GST_VIDEO_INFO_HEIGHT (vip));
}

static GstVaapiSurfaceProxy *
new_surface_proxy (GstVaapiVideoMemory * mem)
{
  GstVaapiVideoAllocator *const allocator =
      GST_VAAPI_VIDEO_ALLOCATOR_CAST (GST_MEMORY_CAST (mem)->allocator);

  return
      gst_vaapi_surface_proxy_new_from_pool (GST_VAAPI_SURFACE_POOL
      (allocator->surface_pool));
}

static gboolean
ensure_surface (GstVaapiVideoMemory * mem)
{
  if (!mem->proxy) {
    gst_vaapi_surface_proxy_replace (&mem->proxy,
        gst_vaapi_video_meta_get_surface_proxy (mem->meta));

    if (!mem->proxy) {
      mem->proxy = new_surface_proxy (mem);
      if (!mem->proxy)
        return FALSE;
      gst_vaapi_video_meta_set_surface_proxy (mem->meta, mem->proxy);
    }
  }
  mem->surface = GST_VAAPI_SURFACE_PROXY_SURFACE (mem->proxy);
  return mem->surface != NULL;
}

gboolean
gst_video_meta_map_vaapi_memory (GstVideoMeta * meta, guint plane,
    GstMapInfo * info, gpointer * data, gint * stride, GstMapFlags flags)
{
  GstVaapiVideoMemory *const mem =
      GST_VAAPI_VIDEO_MEMORY_CAST (gst_buffer_peek_memory (meta->buffer, 0));

  g_return_val_if_fail (mem, FALSE);
  g_return_val_if_fail (GST_VAAPI_IS_VIDEO_ALLOCATOR (mem->parent_instance.
          allocator), FALSE);
  g_return_val_if_fail (mem->meta, FALSE);

  if (mem->map_type && mem->map_type != GST_VAAPI_VIDEO_MEMORY_MAP_TYPE_PLANAR)
    goto error_incompatible_map;

  /* Map for writing */
  if (++mem->map_count == 1) {
    if (!ensure_surface (mem))
      goto error_ensure_surface;
    if (!ensure_image (mem))
      goto error_ensure_image;

    // Check that we can actually map the surface, or image
    if ((flags & GST_MAP_READWRITE) == GST_MAP_READWRITE &&
        !mem->use_direct_rendering)
      goto error_unsupported_map;

    // Load VA image from surface
    if ((flags & GST_MAP_READ) && !mem->use_direct_rendering)
      gst_vaapi_surface_get_image (mem->surface, mem->image);

    if (!gst_vaapi_image_map (mem->image))
      goto error_map_image;
    mem->map_type = GST_VAAPI_VIDEO_MEMORY_MAP_TYPE_PLANAR;
  }

  *data = gst_vaapi_image_get_plane (mem->image, plane);
  *stride = gst_vaapi_image_get_pitch (mem->image, plane);
  info->flags = flags;
  return TRUE;

  /* ERRORS */
error_incompatible_map:
  {
    GST_ERROR ("incompatible map type (%d)", mem->map_type);
    return FALSE;
  }
error_unsupported_map:
  {
    GST_ERROR ("unsupported map flags (0x%x)", flags);
    return FALSE;
  }
error_ensure_surface:
  {
    const GstVideoInfo *const vip = mem->surface_info;
    GST_ERROR ("failed to create %s surface of size %ux%u",
        GST_VIDEO_INFO_FORMAT_STRING (vip),
        GST_VIDEO_INFO_WIDTH (vip), GST_VIDEO_INFO_HEIGHT (vip));
    return FALSE;
  }
error_ensure_image:
  {
    const GstVideoInfo *const vip = mem->image_info;
    GST_ERROR ("failed to create %s image of size %ux%u",
        GST_VIDEO_INFO_FORMAT_STRING (vip),
        GST_VIDEO_INFO_WIDTH (vip), GST_VIDEO_INFO_HEIGHT (vip));
    return FALSE;
  }
error_map_image:
  {
    GST_ERROR ("failed to map image %" GST_VAAPI_ID_FORMAT,
        GST_VAAPI_ID_ARGS (gst_vaapi_image_get_id (mem->image)));
    return FALSE;
  }
}

gboolean
gst_video_meta_unmap_vaapi_memory (GstVideoMeta * meta, guint plane,
    GstMapInfo * info)
{
  GstVaapiVideoMemory *const mem =
      GST_VAAPI_VIDEO_MEMORY_CAST (gst_buffer_peek_memory (meta->buffer, 0));

  g_return_val_if_fail (mem, FALSE);
  g_return_val_if_fail (GST_VAAPI_IS_VIDEO_ALLOCATOR (mem->parent_instance.
          allocator), FALSE);
  g_return_val_if_fail (mem->meta, FALSE);
  g_return_val_if_fail (mem->surface, FALSE);
  g_return_val_if_fail (mem->image, FALSE);

  if (--mem->map_count == 0) {
    mem->map_type = 0;

    /* Unmap VA image used for read/writes */
    if (info->flags & GST_MAP_READWRITE)
      gst_vaapi_image_unmap (mem->image);

    /* Commit VA image to surface */
    if ((info->flags & GST_MAP_WRITE) && !mem->use_direct_rendering) {
      if (!gst_vaapi_surface_put_image (mem->surface, mem->image))
        goto error_upload_image;
    }
  }
  return TRUE;

  /* ERRORS */
error_upload_image:
  {
    GST_ERROR ("failed to upload image");
    return FALSE;
  }
}

GstMemory *
gst_vaapi_video_memory_new (GstAllocator * base_allocator,
    GstVaapiVideoMeta * meta)
{
  GstVaapiVideoAllocator *const allocator =
      GST_VAAPI_VIDEO_ALLOCATOR_CAST (base_allocator);
  const GstVideoInfo *vip;
  GstVaapiVideoMemory *mem;

  mem = g_slice_new (GstVaapiVideoMemory);
  if (!mem)
    return NULL;

  vip = &allocator->image_info;
  gst_memory_init (&mem->parent_instance, GST_MEMORY_FLAG_NO_SHARE,
      gst_object_ref (allocator), NULL, GST_VIDEO_INFO_SIZE (vip), 0,
      0, GST_VIDEO_INFO_SIZE (vip));

  mem->proxy = NULL;
  mem->surface_info = &allocator->surface_info;
  mem->surface = NULL;
  mem->image_info = &allocator->image_info;
  mem->image = NULL;
  mem->meta = meta ? gst_vaapi_video_meta_ref (meta) : NULL;
  mem->map_type = 0;
  mem->map_count = 0;
  mem->use_direct_rendering = allocator->has_direct_rendering;
  return GST_MEMORY_CAST (mem);
}

static void
gst_vaapi_video_memory_free (GstVaapiVideoMemory * mem)
{
  mem->surface = NULL;
  gst_vaapi_video_memory_reset_image (mem);
  gst_vaapi_surface_proxy_replace (&mem->proxy, NULL);
  gst_vaapi_video_meta_replace (&mem->meta, NULL);
  gst_object_unref (GST_MEMORY_CAST (mem)->allocator);
  g_slice_free (GstVaapiVideoMemory, mem);
}

void
gst_vaapi_video_memory_reset_image (GstVaapiVideoMemory * mem)
{
  GstVaapiVideoAllocator *const allocator =
      GST_VAAPI_VIDEO_ALLOCATOR_CAST (GST_MEMORY_CAST (mem)->allocator);

  if (mem->use_direct_rendering)
    gst_vaapi_object_replace (&mem->image, NULL);
  else if (mem->image) {
    gst_vaapi_video_pool_put_object (allocator->image_pool, mem->image);
    mem->image = NULL;
  }
}

void
gst_vaapi_video_memory_reset_surface (GstVaapiVideoMemory * mem)
{
  mem->surface = NULL;
  gst_vaapi_video_memory_reset_image (mem);
  gst_vaapi_surface_proxy_replace (&mem->proxy, NULL);
  if (mem->meta)
    gst_vaapi_video_meta_set_surface_proxy (mem->meta, NULL);
}

static gpointer
gst_vaapi_video_memory_map (GstVaapiVideoMemory * mem, gsize maxsize,
    guint flags)
{
  gpointer data;

  g_return_val_if_fail (mem, NULL);
  g_return_val_if_fail (mem->meta, NULL);

  if (mem->map_count == 0) {
    switch (flags & GST_MAP_READWRITE) {
      case 0:
        // No flags set: return a GstVaapiSurfaceProxy
        gst_vaapi_surface_proxy_replace (&mem->proxy,
            gst_vaapi_video_meta_get_surface_proxy (mem->meta));
        if (!mem->proxy)
          goto error_no_surface_proxy;
        mem->map_type = GST_VAAPI_VIDEO_MEMORY_MAP_TYPE_SURFACE;
        break;
      case GST_MAP_READ:
        // Only read flag set: return raw pixels
        if (!ensure_surface (mem))
          goto error_no_surface;
        if (!ensure_image (mem))
          goto error_no_image;
        if (!mem->use_direct_rendering)
          gst_vaapi_surface_get_image (mem->surface, mem->image);
        if (!gst_vaapi_image_map (mem->image))
          goto error_map_image;
        mem->map_type = GST_VAAPI_VIDEO_MEMORY_MAP_TYPE_LINEAR;
        break;
      default:
        goto error_unsupported_map;
    }
  }

  switch (mem->map_type) {
    case GST_VAAPI_VIDEO_MEMORY_MAP_TYPE_SURFACE:
      if (!mem->proxy)
        goto error_no_surface_proxy;
      data = mem->proxy;
      break;
    case GST_VAAPI_VIDEO_MEMORY_MAP_TYPE_LINEAR:
      if (!mem->image)
        goto error_no_image;
      data = get_image_data (mem->image);
      break;
    default:
      goto error_unsupported_map_type;
  }
  mem->map_count++;
  return data;

  /* ERRORS */
error_unsupported_map:
  GST_ERROR ("unsupported map flags (0x%x)", flags);
  return NULL;
error_unsupported_map_type:
  GST_ERROR ("unsupported map type (%d)", mem->map_type);
  return NULL;
error_no_surface_proxy:
  GST_ERROR ("failed to extract GstVaapiSurfaceProxy from video meta");
  return NULL;
error_no_surface:
  GST_ERROR ("failed to extract VA surface from video buffer");
  return NULL;
error_no_image:
  GST_ERROR ("failed to extract VA image from video buffer");
  return NULL;
error_map_image:
  GST_ERROR ("failed to map VA image");
  return NULL;
}

static void
gst_vaapi_video_memory_unmap (GstVaapiVideoMemory * mem)
{
  if (mem->map_count == 1) {
    switch (mem->map_type) {
      case GST_VAAPI_VIDEO_MEMORY_MAP_TYPE_SURFACE:
        gst_vaapi_surface_proxy_replace (&mem->proxy, NULL);
        break;
      case GST_VAAPI_VIDEO_MEMORY_MAP_TYPE_LINEAR:
        gst_vaapi_image_unmap (mem->image);
        break;
      default:
        goto error_incompatible_map;
    }
    mem->map_type = 0;
  }
  mem->map_count--;
  return;

  /* ERRORS */
error_incompatible_map:
  GST_ERROR ("incompatible map type (%d)", mem->map_type);
  return;
}

static GstVaapiVideoMemory *
gst_vaapi_video_memory_copy (GstVaapiVideoMemory * mem,
    gssize offset, gssize size)
{
  GstVaapiVideoMeta *meta;
  GstMemory *out_mem;
  gsize maxsize;

  g_return_val_if_fail (mem, NULL);
  g_return_val_if_fail (mem->meta, NULL);

  /* XXX: this implements a soft-copy, i.e. underlying VA surfaces
     are not copied */
  (void) gst_memory_get_sizes (GST_MEMORY_CAST (mem), NULL, &maxsize);
  if (offset != 0 || (size != -1 && (gsize) size != maxsize))
    goto error_unsupported;

  meta = gst_vaapi_video_meta_copy (mem->meta);
  if (!meta)
    goto error_allocate_memory;

  out_mem = gst_vaapi_video_memory_new (GST_MEMORY_CAST (mem)->allocator, meta);
  gst_vaapi_video_meta_unref (meta);
  if (!out_mem)
    goto error_allocate_memory;
  return GST_VAAPI_VIDEO_MEMORY_CAST (out_mem);

  /* ERRORS */
error_unsupported:
  GST_ERROR ("failed to copy partial memory (unsupported operation)");
  return NULL;
error_allocate_memory:
  GST_ERROR ("failed to allocate GstVaapiVideoMemory copy");
  return NULL;
}

static GstVaapiVideoMemory *
gst_vaapi_video_memory_share (GstVaapiVideoMemory * mem,
    gssize offset, gssize size)
{
  GST_FIXME ("unimplemented GstVaapiVideoAllocator::mem_share() hook");
  return NULL;
}

static gboolean
gst_vaapi_video_memory_is_span (GstVaapiVideoMemory * mem1,
    GstVaapiVideoMemory * mem2, gsize * offset_ptr)
{
  GST_FIXME ("unimplemented GstVaapiVideoAllocator::mem_is_span() hook");
  return FALSE;
}

/* ------------------------------------------------------------------------ */
/* --- GstVaapiVideoAllocator                                           --- */
/* ------------------------------------------------------------------------ */

#define GST_VAAPI_VIDEO_ALLOCATOR_CLASS(klass) \
  (G_TYPE_CHECK_CLASS_CAST ((klass), GST_VAAPI_TYPE_VIDEO_ALLOCATOR, \
      GstVaapiVideoAllocatorClass))

#define GST_VAAPI_IS_VIDEO_ALLOCATOR_CLASS(klass) \
  (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_VAAPI_TYPE_VIDEO_ALLOCATOR))

G_DEFINE_TYPE (GstVaapiVideoAllocator,
    gst_vaapi_video_allocator, GST_TYPE_ALLOCATOR);

static GstMemory *
gst_vaapi_video_allocator_alloc (GstAllocator * allocator, gsize size,
    GstAllocationParams * params)
{
  g_warning ("use gst_vaapi_video_memory_new() to allocate from "
      "GstVaapiVideoMemory allocator");

  return NULL;
}

static void
gst_vaapi_video_allocator_free (GstAllocator * allocator, GstMemory * mem)
{
  gst_vaapi_video_memory_free (GST_VAAPI_VIDEO_MEMORY_CAST (mem));
}

static void
gst_vaapi_video_allocator_finalize (GObject * object)
{
  GstVaapiVideoAllocator *const allocator =
      GST_VAAPI_VIDEO_ALLOCATOR_CAST (object);

  gst_vaapi_video_pool_replace (&allocator->surface_pool, NULL);
  gst_vaapi_video_pool_replace (&allocator->image_pool, NULL);

  G_OBJECT_CLASS (gst_vaapi_video_allocator_parent_class)->finalize (object);
}

static void
gst_vaapi_video_allocator_class_init (GstVaapiVideoAllocatorClass * klass)
{
  GObjectClass *const object_class = G_OBJECT_CLASS (klass);
  GstAllocatorClass *const allocator_class = GST_ALLOCATOR_CLASS (klass);

  GST_DEBUG_CATEGORY_INIT (gst_debug_vaapivideomemory,
      "vaapivideomemory", 0, "VA-API video memory allocator");

  object_class->finalize = gst_vaapi_video_allocator_finalize;
  allocator_class->alloc = gst_vaapi_video_allocator_alloc;
  allocator_class->free = gst_vaapi_video_allocator_free;
}

static void
gst_vaapi_video_allocator_init (GstVaapiVideoAllocator * allocator)
{
  GstAllocator *const base_allocator = GST_ALLOCATOR_CAST (allocator);

  base_allocator->mem_type = GST_VAAPI_VIDEO_MEMORY_NAME;
  base_allocator->mem_map = (GstMemoryMapFunction)
      gst_vaapi_video_memory_map;
  base_allocator->mem_unmap = (GstMemoryUnmapFunction)
      gst_vaapi_video_memory_unmap;
  base_allocator->mem_copy = (GstMemoryCopyFunction)
      gst_vaapi_video_memory_copy;
  base_allocator->mem_share = (GstMemoryShareFunction)
      gst_vaapi_video_memory_share;
  base_allocator->mem_is_span = (GstMemoryIsSpanFunction)
      gst_vaapi_video_memory_is_span;
}

static gboolean
gst_video_info_update_from_image (GstVideoInfo * vip, GstVaapiImage * image)
{
  GstVideoFormat format;
  const guchar *data;
  guint i, num_planes, data_size, width, height;

  /* Reset format from image */
  format = gst_vaapi_image_get_format (image);
  gst_vaapi_image_get_size (image, &width, &height);
  gst_video_info_set_format (vip, format, width, height);

  num_planes = gst_vaapi_image_get_plane_count (image);
  g_return_val_if_fail (num_planes == GST_VIDEO_INFO_N_PLANES (vip), FALSE);

  /* Determine the base data pointer */
  data = get_image_data (image);
  g_return_val_if_fail (data != NULL, FALSE);
  data_size = gst_vaapi_image_get_data_size (image);

  /* Check that we don't have disjoint planes */
  for (i = 0; i < num_planes; i++) {
    const guchar *const plane = gst_vaapi_image_get_plane (image, i);
    if (plane - data > data_size)
      return FALSE;
  }

  /* Update GstVideoInfo structure */
  for (i = 0; i < num_planes; i++) {
    const guchar *const plane = gst_vaapi_image_get_plane (image, i);
    GST_VIDEO_INFO_PLANE_OFFSET (vip, i) = plane - data;
    GST_VIDEO_INFO_PLANE_STRIDE (vip, i) = gst_vaapi_image_get_pitch (image, i);
  }
  GST_VIDEO_INFO_SIZE (vip) = data_size;
  return TRUE;
}

GstAllocator *
gst_vaapi_video_allocator_new (GstVaapiDisplay * display,
    const GstVideoInfo * vip)
{
  GstVaapiVideoAllocator *allocator;
  GstVaapiSurface *surface;
  GstVaapiImage *image;

  g_return_val_if_fail (display != NULL, NULL);
  g_return_val_if_fail (vip != NULL, NULL);

  allocator = g_object_new (GST_VAAPI_TYPE_VIDEO_ALLOCATOR, NULL);
  if (!allocator)
    return NULL;

  allocator->video_info = *vip;
  gst_video_info_set_format (&allocator->surface_info, GST_VIDEO_FORMAT_NV12,
      GST_VIDEO_INFO_WIDTH (vip), GST_VIDEO_INFO_HEIGHT (vip));

  if (GST_VIDEO_INFO_FORMAT (vip) != GST_VIDEO_FORMAT_ENCODED) {
    image = NULL;
    do {
      surface = new_surface (display, vip);
      if (!surface)
        break;
      image = gst_vaapi_surface_derive_image (surface);
      if (!image)
        break;
      if (!gst_vaapi_image_map (image))
        break;
      allocator->has_direct_rendering =
          gst_video_info_update_from_image (&allocator->surface_info, image);
      if (GST_VAAPI_IMAGE_FORMAT (image) != GST_VIDEO_INFO_FORMAT (vip))
        allocator->has_direct_rendering = FALSE;
      if (USE_NATIVE_FORMATS)
        allocator->has_direct_rendering = FALSE;
      gst_vaapi_image_unmap (image);
      GST_INFO ("has direct-rendering for %s surfaces: %s",
          GST_VIDEO_INFO_FORMAT_STRING (&allocator->surface_info),
          allocator->has_direct_rendering ? "yes" : "no");
    } while (0);
    if (surface)
      gst_vaapi_object_unref (surface);
    if (image)
      gst_vaapi_object_unref (image);
  }

  allocator->surface_pool = gst_vaapi_surface_pool_new (display,
      &allocator->surface_info);
  if (!allocator->surface_pool)
    goto error_create_surface_pool;

  allocator->image_info = *vip;
  if (GST_VIDEO_INFO_FORMAT (vip) == GST_VIDEO_FORMAT_ENCODED)
    gst_video_info_set_format (&allocator->image_info, GST_VIDEO_FORMAT_I420,
        GST_VIDEO_INFO_WIDTH (vip), GST_VIDEO_INFO_HEIGHT (vip));

  if (allocator->has_direct_rendering)
    allocator->image_info = allocator->surface_info;
  else {
    do {
      image = new_image (display, &allocator->image_info);
      if (!image)
        break;
      if (!gst_vaapi_image_map (image))
        break;
      gst_video_info_update_from_image (&allocator->image_info, image);
      gst_vaapi_image_unmap (image);
    } while (0);
    if (image)
      gst_vaapi_object_unref (image);
  }

  allocator->image_pool = gst_vaapi_image_pool_new (display,
      &allocator->image_info);
  if (!allocator->image_pool)
    goto error_create_image_pool;
  return GST_ALLOCATOR_CAST (allocator);

  /* ERRORS */
error_create_surface_pool:
  {
    GST_ERROR ("failed to allocate VA surface pool");
    gst_object_unref (allocator);
    return NULL;
  }
error_create_image_pool:
  {
    GST_ERROR ("failed to allocate VA image pool");
    gst_object_unref (allocator);
    return NULL;
  }
}