FFmpeg  4.0
v4l2_buffers.h
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1 /*
2  * V4L2 buffer helper functions.
3  *
4  * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
5  * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
6  *
7  * This file is part of FFmpeg.
8  *
9  * FFmpeg is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * FFmpeg is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with FFmpeg; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
24 #ifndef AVCODEC_V4L2_BUFFERS_H
25 #define AVCODEC_V4L2_BUFFERS_H
26 
27 #include <stdatomic.h>
28 #include <linux/videodev2.h>
29 
30 #include "avcodec.h"
31 
36 };
37 
38 /**
39  * V4L2Buffer (wrapper for v4l2_buffer management)
40  */
41 typedef struct V4L2Buffer {
42  /* each buffer needs to have a reference to its context */
44 
45  /* This object is refcounted per-plane, so we need to keep track
46  * of how many context-refs we are holding. */
49 
50  /* keep track of the mmap address and mmap length */
51  struct V4L2Plane_info {
53  void * mm_addr;
54  size_t length;
55  } plane_info[VIDEO_MAX_PLANES];
56 
58 
59  /* the v4l2_buffer buf.m.planes pointer uses the planes[] mem */
60  struct v4l2_buffer buf;
61  struct v4l2_plane planes[VIDEO_MAX_PLANES];
62 
63  int flags;
65 
66 } V4L2Buffer;
67 
68 /**
69  * Extracts the data from a V4L2Buffer to an AVFrame
70  *
71  * @param[in] frame The AVFRame to push the information to
72  * @param[in] buf The V4L2Buffer to get the information from
73  *
74  * @returns 0 in case of success, AVERROR(EINVAL) if the number of planes is incorrect,
75  * AVERROR(ENOMEM) if the AVBufferRef cant be created.
76  */
78 
79 /**
80  * Extracts the data from a V4L2Buffer to an AVPacket
81  *
82  * @param[in] pkt The AVPacket to push the information to
83  * @param[in] buf The V4L2Buffer to get the information from
84  *
85  * @returns 0 in case of success, AVERROR(EINVAL) if the number of planes is incorrect,
86  * AVERROR(ENOMEM) if the AVBufferRef cant be created.
87  *
88  */
90 
91 /**
92  * Extracts the data from an AVPacket to a V4L2Buffer
93  *
94  * @param[in] frame AVPacket to get the data from
95  * @param[in] avbuf V4L2Bfuffer to push the information to
96  *
97  * @returns 0 in case of success, a negative AVERROR code otherwise
98  */
100 
101 /**
102  * Extracts the data from an AVFrame to a V4L2Buffer
103  *
104  * @param[in] frame AVFrame to get the data from
105  * @param[in] avbuf V4L2Bfuffer to push the information to
106  *
107  * @returns 0 in case of success, a negative AVERROR code otherwise
108  */
110 
111 /**
112  * Initializes a V4L2Buffer
113  *
114  * @param[in] avbuf V4L2Bfuffer to initialize
115  * @param[in] index v4l2 buffer id
116  *
117  * @returns 0 in case of success, a negative AVERROR code otherwise
118  */
120 
121 /**
122  * Enqueues a V4L2Buffer
123  *
124  * @param[in] avbuf V4L2Bfuffer to push to the driver
125  *
126  * @returns 0 in case of success, a negative AVERROR code otherwise
127  */
129 
130 
131 #endif // AVCODEC_V4L2_BUFFERS_H
int ff_v4l2_buffer_avframe_to_buf(const AVFrame *frame, V4L2Buffer *out)
Extracts the data from an AVFrame to a V4L2Buffer.
Definition: v4l2_buffers.c:289
V4L2Buffer_status
Definition: v4l2_buffers.h:32
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
int ff_v4l2_buffer_buf_to_avframe(AVFrame *frame, V4L2Buffer *buf)
Extracts the data from a V4L2Buffer to an AVFrame.
Definition: v4l2_buffers.c:304
int ff_v4l2_buffer_enqueue(V4L2Buffer *avbuf)
Enqueues a V4L2Buffer.
Definition: v4l2_buffers.c:465
static AVPacket pkt
enum V4L2Buffer_status status
Definition: v4l2_buffers.h:64
int ff_v4l2_buffer_initialize(V4L2Buffer *avbuf, int index)
Initializes a V4L2Buffer.
Definition: v4l2_buffers.c:396
static AVFrame * frame
struct V4L2Context * context
Definition: v4l2_buffers.h:43
int ff_v4l2_buffer_buf_to_avpkt(AVPacket *pkt, V4L2Buffer *buf)
Extracts the data from a V4L2Buffer to an AVPacket.
Definition: v4l2_buffers.c:355
struct v4l2_buffer buf
Definition: v4l2_buffers.h:60
AVBufferRef * context_ref
Definition: v4l2_buffers.h:47
struct v4l2_plane planes[VIDEO_MAX_PLANES]
Definition: v4l2_buffers.h:61
atomic_uint context_refcount
Definition: v4l2_buffers.h:48
Libavcodec external API header.
V4L2Buffer (wrapper for v4l2_buffer management)
Definition: v4l2_buffers.h:41
int index
Definition: gxfenc.c:89
intptr_t atomic_uint
Definition: stdatomic.h:56
A reference to a data buffer.
Definition: buffer.h:81
int num_planes
Definition: v4l2_buffers.h:57
int ff_v4l2_buffer_avpkt_to_buf(const AVPacket *pkt, V4L2Buffer *out)
Extracts the data from an AVPacket to a V4L2Buffer.
Definition: v4l2_buffers.c:380
FILE * out
Definition: movenc.c:54
This structure stores compressed data.
Definition: avcodec.h:1407