/* GStreamer video frame cropping
 * Copyright (C) 2006 Tim-Philipp Müller <tim centricular net>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

/**
 * SECTION:element-videocrop
 * @title: videocrop
 * @see_also: #GstVideoBox
 *
 * This element crops video frames, meaning it can remove parts of the
 * picture on the left, right, top or bottom of the picture and output
 * a smaller picture than the input picture, with the unwanted parts at the
 * border removed.
 *
 * The videocrop element is similar to the videobox element, but its main
 * goal is to support a multitude of formats as efficiently as possible.
 * Unlike videbox, it cannot add borders to the picture and unlike videbox
 * it will always output images in exactly the same format as the input image.
 *
 * If there is nothing to crop, the element will operate in pass-through mode.
 *
 * Note that no special efforts are made to handle chroma-subsampled formats
 * in the case of odd-valued cropping and compensate for sub-unit chroma plane
 * shifts for such formats in the case where the #GstVideoCrop:left or
 * #GstVideoCrop:top property is set to an odd number. This doesn't matter for
 * most use cases, but it might matter for yours.
 *
 * ## Example launch line
 * |[
 * gst-launch-1.0 -v videotestsrc ! videocrop top=42 left=1 right=4 bottom=0 ! ximagesink
 * ]|
 *
 */

/* TODO:
 *  - for packed formats, we could avoid memcpy() in case crop_left
 *    and crop_right are 0 and just create a sub-buffer of the input
 *    buffer
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <gst/gst.h>
#include <gst/video/video.h>

#include "gstvideocropelements.h"

GST_DEBUG_CATEGORY_STATIC (videocrop_debug);
#define GST_CAT_DEFAULT videocrop_debug

void
videocrop_element_init (GstPlugin * plugin)
{
  static gsize res = FALSE;
  if (g_once_init_enter (&res)) {
    GST_DEBUG_CATEGORY_INIT (videocrop_debug, "videocrop", 0, "videocrop");
    g_once_init_leave (&res, TRUE);
  }
}