gstreamer/gst-libs/gst/video/gstvideoaffinetransformationmeta.c
2018-04-02 16:49:19 +02:00

160 lines
4.5 KiB
C

/* GStreamer
* Copyright (C) <2014> Collabora Ltd.
* Author: Matthieu Bouron <matthieu.bouron@gmail.com>
* Copyright (C) 2015, Matthew Waters <matthew@centricular.com>
*
* 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.
*/
#include "gstvideoaffinetransformationmeta.h"
#include <string.h>
/**
* SECTION:gstvideoaffinetransformationmeta
* @title: GstVideoAffineTransformationMeta
* @short_description: GstMeta for video affine transformation
*
*/
GType
gst_video_affine_transformation_meta_api_get_type (void)
{
static volatile GType type = 0;
static const gchar *tags[] =
{ GST_META_TAG_VIDEO_STR, GST_META_TAG_VIDEO_ORIENTATION_STR,
GST_META_TAG_VIDEO_ORIENTATION_STR, NULL
};
if (g_once_init_enter (&type)) {
GType _type =
gst_meta_api_type_register ("GstVideoAffineTransformationAPI", tags);
g_once_init_leave (&type, _type);
}
return type;
}
static gboolean
gst_video_affine_transformation_meta_transform (GstBuffer * dest,
GstMeta * meta, GstBuffer * buffer, GQuark type, gpointer data)
{
GstVideoAffineTransformationMeta *dmeta, *smeta;
smeta = (GstVideoAffineTransformationMeta *) meta;
if (GST_META_TRANSFORM_IS_COPY (type)) {
dmeta =
(GstVideoAffineTransformationMeta *) gst_buffer_add_meta (dest,
GST_VIDEO_AFFINE_TRANSFORMATION_META_INFO, NULL);
if (!dmeta)
return FALSE;
memcpy (dmeta->matrix, smeta->matrix, sizeof (dmeta->matrix[0]) * 16);
}
return TRUE;
}
static gboolean
gst_video_affine_transformation_meta_init (GstMeta * meta, gpointer params,
GstBuffer * buffer)
{
GstVideoAffineTransformationMeta *af_meta =
(GstVideoAffineTransformationMeta *) meta;
gfloat matrix[] = {
1.0f, 0.0f, 0.0f, 0.0f,
0.0f, 1.0f, 0.0f, 0.0f,
0.0f, 0.0f, 1.0f, 0.0f,
0.0f, 0.0f, 0.0f, 1.0f
};
memcpy (af_meta->matrix, matrix, sizeof (matrix[0]) * 16);
return TRUE;
}
const GstMetaInfo *
gst_video_affine_transformation_meta_get_info (void)
{
static const GstMetaInfo *info = NULL;
if (g_once_init_enter ((GstMetaInfo **) & info)) {
const GstMetaInfo *meta =
gst_meta_register (GST_VIDEO_AFFINE_TRANSFORMATION_META_API_TYPE,
"GstVideoAffineTransformationMeta",
sizeof (GstVideoAffineTransformationMeta),
gst_video_affine_transformation_meta_init,
NULL,
gst_video_affine_transformation_meta_transform);
g_once_init_leave ((GstMetaInfo **) & info, (GstMetaInfo *) meta);
}
return info;
}
/**
* gst_buffer_add_video_affine_transformation_meta:
* @buffer: a #GstBuffer
*
* Attaches GstVideoAffineTransformationMeta metadata to @buffer with
* the given parameters.
*
* Returns: (transfer none): the #GstVideoAffineTransformationMeta on @buffer.
*
* Since: 1.8
*/
GstVideoAffineTransformationMeta *
gst_buffer_add_video_affine_transformation_meta (GstBuffer * buffer)
{
GstVideoAffineTransformationMeta *meta;
g_return_val_if_fail (buffer != NULL, NULL);
meta =
(GstVideoAffineTransformationMeta *) gst_buffer_add_meta (buffer,
GST_VIDEO_AFFINE_TRANSFORMATION_META_INFO, NULL);
if (!meta)
return NULL;
return meta;
}
/**
* gst_video_affine_transformation_meta_apply_matrix:
* @meta: a #GstVideoAffineTransformationMeta
* @matrix: a 4x4 transformation matrix to be applied
*
* Apply a transformation using the given 4x4 transformation matrix.
* Performs the multiplication, meta->matrix X matrix.
*
* Since: 1.8
*/
void gst_video_affine_transformation_meta_apply_matrix
(GstVideoAffineTransformationMeta * meta, const gfloat matrix[16])
{
gfloat res[16] = { 0.0f };
int i, j, k;
for (i = 0; i < 4; i++) {
for (j = 0; j < 4; j++) {
for (k = 0; k < 4; k++) {
res[i + (j * 4)] += meta->matrix[i + (k * 4)] * matrix[k + (j * 4)];
}
}
}
memcpy (meta->matrix, res, sizeof (meta->matrix[0]) * 16);
}