mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-12-20 23:36:38 +00:00
936b2fdfbc
Implement a new memory type wrapping CVPixelBuffer.
There are two immediate advantages:
a) Make the GstMemory itself retain the CVPixelBuffer. Previously,
the containing GstBuffer was solely responsible for the lifetime of
the backing CVPixelBuffer.
With this change, we remove the GST_MEMORY_FLAG_NO_SHARE so that
GstMemory objects be referenced by multiple GstBuffers (doing away
with the need to copy.)
b) Delay locking CVPixelBuffer into CPU memory until it's actually
mapped -- possibly never.
The CVPixelBuffer object is shared among references, shares and
(in planar formats) planes, so a wrapper GstAppleCoreVideoPixelBuffer
structure was introduced to manage locking.
https://bugzilla.gnome.org/show_bug.cgi?id=747216
109 lines
3.1 KiB
C
109 lines
3.1 KiB
C
/* GStreamer Apple Core Video memory
|
||
* Copyright (C) 2015 Ilya Konstantinov
|
||
*
|
||
* 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., 59 Temple Place - Suite 330,
|
||
* Boston, MA 02111-1307, USA.
|
||
*/
|
||
|
||
#ifndef __GST_APPLE_CORE_VIDEO_MEMORY_H__
|
||
#define __GST_APPLE_CORE_VIDEO_MEMORY_H__
|
||
|
||
#include <gst/gst.h>
|
||
|
||
#include "CoreVideo/CoreVideo.h"
|
||
|
||
G_BEGIN_DECLS
|
||
|
||
/**
|
||
* GstAppleCoreVideoLockState:
|
||
*
|
||
* Specifies whether the backing CVPixelBuffer is locked for read-only
|
||
* or read-write.
|
||
*
|
||
* Locking for reading only improves performance by preventing
|
||
* Core Video from invalidating existing caches of the buffer’s contents.
|
||
*/
|
||
typedef enum
|
||
{
|
||
GST_APPLE_CORE_VIDEO_MEMORY_UNLOCKED,
|
||
GST_APPLE_CORE_VIDEO_MEMORY_LOCKED_READONLY,
|
||
GST_APPLE_CORE_VIDEO_MEMORY_LOCKED_READ_WRITE
|
||
} GstAppleCoreVideoLockState;
|
||
|
||
/**
|
||
* GstAppleCoreVideoPixelBuffer:
|
||
*
|
||
* This structure wraps CVPixelBuffer, managing its lock states and reference count.
|
||
* It will be referenced by one or more #GstAppleCoreVideoMemory.
|
||
*/
|
||
typedef struct
|
||
{
|
||
guint refcount;
|
||
GMutex mutex;
|
||
CVPixelBufferRef buf;
|
||
/* Allows mem_map to refuse Read-Write locking a buffer that was previously
|
||
* locked for Read-Only. */
|
||
GstAppleCoreVideoLockState lock_state;
|
||
/* Counts the number of times the buffer was locked.
|
||
* Only the first lock affects whether it's just for reading
|
||
* or for reading and writing, as reflected in @lock_state. */
|
||
guint lock_count;
|
||
} GstAppleCoreVideoPixelBuffer;
|
||
|
||
/**
|
||
* GST_APPLE_CORE_VIDEO_NO_PLANE:
|
||
*
|
||
* Indicates a non-planar pixel buffer.
|
||
*/
|
||
#define GST_APPLE_CORE_VIDEO_NO_PLANE ((size_t)-1)
|
||
|
||
/**
|
||
* GstAppleCoreVideoMemory:
|
||
*
|
||
* Represents a video plane or an entire (non-planar) video image,
|
||
* backed by a CVPixelBuffer.
|
||
*
|
||
* This structure shares a #GstAppleCoreVideoPixelBuffer instance
|
||
* with other instances.
|
||
*/
|
||
typedef struct
|
||
{
|
||
GstMemory mem;
|
||
|
||
GstAppleCoreVideoPixelBuffer *gpixbuf;
|
||
size_t plane;
|
||
} GstAppleCoreVideoMemory;
|
||
|
||
void
|
||
gst_apple_core_video_memory_init (void);
|
||
|
||
GstAppleCoreVideoPixelBuffer *
|
||
gst_apple_core_video_pixel_buffer_new (CVPixelBufferRef pixbuf);
|
||
|
||
GstAppleCoreVideoPixelBuffer *
|
||
gst_apple_core_video_pixel_buffer_ref (GstAppleCoreVideoPixelBuffer * shared);
|
||
|
||
void
|
||
gst_apple_core_video_pixel_buffer_unref (GstAppleCoreVideoPixelBuffer * shared);
|
||
|
||
gboolean
|
||
gst_is_apple_core_video_memory (GstMemory * mem);
|
||
|
||
GstMemory *
|
||
gst_apple_core_video_memory_new_wrapped (GstAppleCoreVideoPixelBuffer * shared, gsize plane, gsize size);
|
||
|
||
G_END_DECLS
|
||
|
||
#endif /* __GST_APPLE_CORE_VIDEO_MEMORY_H__ */
|