gstreamer/gst-libs/gst/video/gstvideoaffinetransformationmeta.h
Matthew Waters 1e3f5e0ecf video/affinetransformationmeta: define the coordinate space used
Based on the expected output from the already existing usage by androidmedia
and the opengl plugins.

https://bugzilla.gnome.org/show_bug.cgi?id=764667
2016-05-15 10:53:55 +03:00

77 lines
3.2 KiB
C

/* GStreamer
* Copyright (C) Collabora Ltd.
* Author: Matthieu Bouron <matthieu.bouron@collabora.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.
*/
#ifndef __GST_VIDEO_AFFINE_TRANSFORMATION_META_H__
#define __GST_VIDEO_AFFINE_TRANSFORMATION_META_H__
#include <gst/gst.h>
#include <gst/video/video.h>
G_BEGIN_DECLS
#define GST_VIDEO_AFFINE_TRANSFORMATION_META_API_TYPE (gst_video_affine_transformation_meta_api_get_type())
#define GST_VIDEO_AFFINE_TRANSFORMATION_META_INFO (gst_video_affine_transformation_meta_get_info())
typedef struct _GstVideoAffineTransformationMeta GstVideoAffineTransformationMeta;
typedef gboolean (*GstVideoAffineTransformationGetMatrix) (GstVideoAffineTransformationMeta * meta, gfloat * matrix);
#define GST_CAPS_FEATURE_META_GST_VIDEO_AFFINE_TRANSFORMATION_META "meta:GstVideoAffineTransformation"
#define GST_BUFFER_POOL_OPTION_VIDEO_AFFINE_TRANSFORMATION_META "GstBufferPoolOptionVideoAffineTransformation"
/**
* GstVideoAffineTransformation:
* @meta: parent #GstMeta
* @matrix: the column-major 4x4 transformation matrix
*
* Extra buffer metadata for performing an affine transformation using a 4x4
* matrix. The transformation matrix can be composed with
* gst_video_affine_transformation_meta_apply_matrix().
*
* The vertices operated on are all in the range 0 to 1, not in
* Normalized Device Coordinates (-1 to +1). Transforming points in this space
* are assumed to have an origin at (0.5, 0.5, 0.5) in a left-handed coordinate
* system with the x-axis moving horizontally (positive values to the right),
* the y-axis moving vertically (positive values up the screen) and the z-axis
* perpendicular to the screen (positive values into the screen).
*
* Since: 1.8
*/
struct _GstVideoAffineTransformationMeta
{
GstMeta meta;
gfloat matrix[16];
};
GType gst_video_affine_transformation_meta_api_get_type (void);
const GstMetaInfo *gst_video_affine_transformation_meta_get_info (void);
#define gst_buffer_get_video_affine_transformation_meta(b) \
((GstVideoAffineTransformationMeta *)gst_buffer_get_meta((b),GST_VIDEO_AFFINE_TRANSFORMATION_META_API_TYPE))
GstVideoAffineTransformationMeta *gst_buffer_add_video_affine_transformation_meta (GstBuffer * buffer);
void gst_video_affine_transformation_meta_apply_matrix (GstVideoAffineTransformationMeta * meta,
const gfloat matrix[16]);
G_END_DECLS
#endif /* __GST_VIDEO_AFFINE_TRANSFORMATION_META_H__ */