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77 lines
2.6 KiB
C
77 lines
2.6 KiB
C
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/* GStreamer video frame cropping
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* Copyright (C) 2006 Tim-Philipp Müller <tim centricular net>
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Library General Public
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* License as published by the Free Software Foundation; either
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* version 2 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Library General Public License for more details.
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*
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* You should have received a copy of the GNU Library General Public
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* License along with this library; if not, write to the
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* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
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* Boston, MA 02110-1301, USA.
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*/
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/**
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* SECTION:element-videocrop
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* @title: videocrop
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* @see_also: #GstVideoBox
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*
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* This element crops video frames, meaning it can remove parts of the
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* picture on the left, right, top or bottom of the picture and output
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* a smaller picture than the input picture, with the unwanted parts at the
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* border removed.
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*
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* The videocrop element is similar to the videobox element, but its main
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* goal is to support a multitude of formats as efficiently as possible.
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* Unlike videbox, it cannot add borders to the picture and unlike videbox
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* it will always output images in exactly the same format as the input image.
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*
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* If there is nothing to crop, the element will operate in pass-through mode.
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*
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* Note that no special efforts are made to handle chroma-subsampled formats
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* in the case of odd-valued cropping and compensate for sub-unit chroma plane
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* shifts for such formats in the case where the #GstVideoCrop:left or
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* #GstVideoCrop:top property is set to an odd number. This doesn't matter for
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* most use cases, but it might matter for yours.
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*
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* ## Example launch line
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* |[
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* gst-launch-1.0 -v videotestsrc ! videocrop top=42 left=1 right=4 bottom=0 ! ximagesink
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* ]|
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*
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*/
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/* TODO:
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* - for packed formats, we could avoid memcpy() in case crop_left
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* and crop_right are 0 and just create a sub-buffer of the input
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* buffer
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*/
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#include <gst/gst.h>
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#include <gst/video/video.h>
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#include "gstvideocropelements.h"
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GST_DEBUG_CATEGORY_STATIC (videocrop_debug);
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#define GST_CAT_DEFAULT videocrop_debug
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void
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videocrop_element_init (GstPlugin * plugin)
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{
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static gsize res = FALSE;
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if (g_once_init_enter (&res)) {
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GST_DEBUG_CATEGORY_INIT (videocrop_debug, "videocrop", 0, "videocrop");
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g_once_init_leave (&res, TRUE);
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}
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}
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