av1/common/frame_buffers.c

/*
 * Copyright (c) 2021, Alliance for Open Media. All rights reserved
 *
 * This source code is subject to the terms of the BSD 3-Clause Clear License
 * and the Alliance for Open Media Patent License 1.0. If the BSD 3-Clause Clear
 * License was not distributed with this source code in the LICENSE file, you
 * can obtain it at aomedia.org/license/software-license/bsd-3-c-c/.  If the
 * Alliance for Open Media Patent License 1.0 was not distributed with this
 * source code in the PATENTS file, you can obtain it at
 * aomedia.org/license/patent-license/.
 */

#include <assert.h>

#include "av1/common/frame_buffers.h"
#include "aom_mem/aom_mem.h"

int av1_alloc_internal_frame_buffers(InternalFrameBufferList *list) {
  assert(list != NULL);
  av1_free_internal_frame_buffers(list);

  list->num_internal_frame_buffers =
      AOM_MAXIMUM_REF_BUFFERS + AOM_MAXIMUM_WORK_BUFFERS;
  list->int_fb = (InternalFrameBuffer *)aom_calloc(
      list->num_internal_frame_buffers, sizeof(*list->int_fb));
  if (list->int_fb == NULL) {
    list->num_internal_frame_buffers = 0;
    return 1;
  }
  return 0;
}

void av1_free_internal_frame_buffers(InternalFrameBufferList *list) {
  int i;

  assert(list != NULL);

  for (i = 0; i < list->num_internal_frame_buffers; ++i) {
    aom_free(list->int_fb[i].data);
    list->int_fb[i].data = NULL;
  }
  aom_free(list->int_fb);
  list->int_fb = NULL;
  list->num_internal_frame_buffers = 0;
}

void av1_zero_unused_internal_frame_buffers(InternalFrameBufferList *list) {
  int i;

  assert(list != NULL);

  for (i = 0; i < list->num_internal_frame_buffers; ++i) {
    if (list->int_fb[i].data && !list->int_fb[i].in_use)
      memset(list->int_fb[i].data, 0, list->int_fb[i].size);
  }
}

int av1_get_frame_buffer(void *cb_priv, size_t min_size,
                         aom_codec_frame_buffer_t *fb) {
  int i;
  InternalFrameBufferList *const int_fb_list =
      (InternalFrameBufferList *)cb_priv;
  if (int_fb_list == NULL) return -1;

  // Find a free frame buffer.
  for (i = 0; i < int_fb_list->num_internal_frame_buffers; ++i) {
    if (!int_fb_list->int_fb[i].in_use) break;
  }

  if (i == int_fb_list->num_internal_frame_buffers) return -1;

  if (int_fb_list->int_fb[i].size < min_size) {
    aom_free(int_fb_list->int_fb[i].data);
    // The data must be zeroed to fix a valgrind error from the C loop filter
    // due to access uninitialized memory in frame border. It could be
    // skipped if border were totally removed.
    int_fb_list->int_fb[i].data = (uint8_t *)aom_calloc(1, min_size);
    if (!int_fb_list->int_fb[i].data) {
      int_fb_list->int_fb[i].size = 0;
      return -1;
    }
    int_fb_list->int_fb[i].size = min_size;
  }

  fb->data = int_fb_list->int_fb[i].data;
  fb->size = int_fb_list->int_fb[i].size;
  int_fb_list->int_fb[i].in_use = 1;

  // Set the frame buffer's private data to point at the internal frame buffer.
  fb->priv = &int_fb_list->int_fb[i];
  return 0;
}

int av1_release_frame_buffer(void *cb_priv, aom_codec_frame_buffer_t *fb) {
  InternalFrameBuffer *const int_fb = (InternalFrameBuffer *)fb->priv;
  (void)cb_priv;
  if (int_fb) int_fb->in_use = 0;
  return 0;
}