static gboolean
gst_eglimage_to_gl_texture_upload_meta (GstVideoGLTextureUploadMeta *
    meta, guint texture_id[4])
{
  gint i = 0;
  gint n = 0;

  g_return_val_if_fail (meta != NULL, FALSE);
  g_return_val_if_fail (texture_id != NULL, FALSE);

  GST_DEBUG ("Uploading for meta with textures %i,%i,%i,%i", texture_id[0],
      texture_id[1], texture_id[2], texture_id[3]);

  n = gst_buffer_n_memory (meta->buffer);

  for (i = 0; i < n; i++) {
    GstMemory *mem = gst_buffer_peek_memory (meta->buffer, i);
    const GstGLFuncs *gl = NULL;

    if (!gst_is_egl_image_memory (mem)) {
      GST_WARNING ("memory %p does not hold an EGLImage", mem);
      return FALSE;
    }

    gl = GST_GL_CONTEXT (GST_EGL_IMAGE_MEMORY (mem)->context)->gl_vtable;

    gl->ActiveTexture (GL_TEXTURE0 + i);
    gl->BindTexture (GL_TEXTURE_2D, texture_id[i]);
    gl->EGLImageTargetTexture2D (GL_TEXTURE_2D,
        gst_egl_image_memory_get_image (mem));
  }

  if (GST_IS_GL_BUFFER_POOL (meta->buffer->pool))
    gst_gl_buffer_pool_replace_last_buffer (GST_GL_BUFFER_POOL (meta->
            buffer->pool), meta->buffer);


  return TRUE;
}
static gboolean
gst_gl_test_src_decide_allocation (GstBaseSrc * basesrc, GstQuery * query)
{
  GstGLTestSrc *src = GST_GL_TEST_SRC (basesrc);
  GstBufferPool *pool = NULL;
  GstStructure *config;
  GstCaps *caps;
  guint min, max, size;
  gboolean update_pool;
  GError *error = NULL;

  if (!gst_gl_ensure_element_data (src, &src->display, &src->other_context))
    return FALSE;

  gst_gl_display_filter_gl_api (src->display, SUPPORTED_GL_APIS);

  _find_local_gl_context (src);

  if (!src->context) {
    GST_OBJECT_LOCK (src->display);
    do {
      if (src->context) {
        gst_object_unref (src->context);
        src->context = NULL;
      }
      /* just get a GL context.  we don't care */
      src->context =
          gst_gl_display_get_gl_context_for_thread (src->display, NULL);
      if (!src->context) {
        if (!gst_gl_display_create_context (src->display, src->other_context,
                &src->context, &error)) {
          GST_OBJECT_UNLOCK (src->display);
          goto context_error;
        }
      }
    } while (!gst_gl_display_add_context (src->display, src->context));
    GST_OBJECT_UNLOCK (src->display);
  }

  if ((gst_gl_context_get_gl_api (src->context) & SUPPORTED_GL_APIS) == 0)
    goto unsupported_gl_api;

  gst_gl_context_thread_add (src->context,
      (GstGLContextThreadFunc) _src_generate_fbo_gl, src);
  if (!src->fbo)
    goto context_error;

  gst_query_parse_allocation (query, &caps, NULL);

  if (gst_query_get_n_allocation_pools (query) > 0) {
    gst_query_parse_nth_allocation_pool (query, 0, &pool, &size, &min, &max);

    update_pool = TRUE;
  } else {
    GstVideoInfo vinfo;

    gst_video_info_init (&vinfo);
    gst_video_info_from_caps (&vinfo, caps);
    size = vinfo.size;
    min = max = 0;
    update_pool = FALSE;
  }

  if (!pool || !GST_IS_GL_BUFFER_POOL (pool)) {
    /* can't use this pool */
    if (pool)
      gst_object_unref (pool);
    pool = gst_gl_buffer_pool_new (src->context);
  }
  config = gst_buffer_pool_get_config (pool);

  gst_buffer_pool_config_set_params (config, caps, size, min, max);
  gst_buffer_pool_config_add_option (config, GST_BUFFER_POOL_OPTION_VIDEO_META);
  if (gst_query_find_allocation_meta (query, GST_GL_SYNC_META_API_TYPE, NULL))
    gst_buffer_pool_config_add_option (config,
        GST_BUFFER_POOL_OPTION_GL_SYNC_META);
  gst_buffer_pool_config_add_option (config,
      GST_BUFFER_POOL_OPTION_VIDEO_GL_TEXTURE_UPLOAD_META);

  gst_buffer_pool_set_config (pool, config);

  if (update_pool)
    gst_query_set_nth_allocation_pool (query, 0, pool, size, min, max);
  else
    gst_query_add_allocation_pool (query, pool, size, min, max);

  gst_gl_test_src_init_shader (src);

  gst_object_unref (pool);

  return TRUE;

unsupported_gl_api:
  {
    GstGLAPI gl_api = gst_gl_context_get_gl_api (src->context);
    gchar *gl_api_str = gst_gl_api_to_string (gl_api);
    gchar *supported_gl_api_str = gst_gl_api_to_string (SUPPORTED_GL_APIS);
    GST_ELEMENT_ERROR (src, RESOURCE, BUSY,
        ("GL API's not compatible context: %s supported: %s", gl_api_str,
            supported_gl_api_str), (NULL));

    g_free (supported_gl_api_str);
    g_free (gl_api_str);
    return FALSE;
  }
context_error:
  {
    GST_ELEMENT_ERROR (src, RESOURCE, NOT_FOUND, ("%s", error->message),
        (NULL));
    g_clear_error (&error);
    if (src->context)
      gst_object_unref (src->context);
    src->context = NULL;
    return FALSE;
  }
}