FFmpeg
v4l2_m2m.h
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1 /*
2  * V4L2 mem2mem 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_M2M_H
25 #define AVCODEC_V4L2_M2M_H
26 
27 #include <semaphore.h>
28 #include <unistd.h>
29 #include <dirent.h>
30 #include <linux/videodev2.h>
31 
32 #include "libavcodec/avcodec.h"
33 #include "v4l2_context.h"
34 
35 #define container_of(ptr, type, member) ({ \
36  const __typeof__(((type *)0)->member ) *__mptr = (ptr); \
37  (type *)((char *)__mptr - offsetof(type,member) );})
38 
39 #define V4L_M2M_DEFAULT_OPTS \
40  { "num_output_buffers", "Number of buffers in the output context",\
41  OFFSET(num_output_buffers), AV_OPT_TYPE_INT, { .i64 = 16 }, 6, INT_MAX, FLAGS }
42 
43 typedef struct V4L2m2mContext {
44  char devname[PATH_MAX];
45  int fd;
46 
47  /* the codec context queues */
50 
51  /* dynamic stream reconfig */
55  int reinit;
56 
57  /* null frame/packet received */
58  int draining;
60 
61  /* Reference to self; only valid while codec is active. */
63 
64  /* reference back to V4L2m2mPriv */
65  void *priv;
67 
68 typedef struct V4L2m2mPriv {
69  AVClass *class;
70 
73 
76 } V4L2m2mPriv;
77 
78 /**
79  * Allocate a new context and references for a V4L2 M2M instance.
80  *
81  * @param[in] ctx The V4L2m2mPriv instantiated by the encoder/decoder.
82  * @param[out] ctx The V4L2m2mContext.
83  *
84  * @returns 0 in success, a negative error code otherwise.
85  */
87 
88 
89 /**
90  * Probes the video nodes looking for the required codec capabilities.
91  *
92  * @param[in] ctx The V4L2m2mPriv instantiated by the encoder/decoder.
93  *
94  * @returns 0 if a driver is found, a negative number otherwise.
95  */
97 
98 /**
99  * Releases all the codec resources if all AVBufferRefs have been returned to the
100  * ctx. Otherwise keep the driver open.
101  *
102  * @param[in] The V4L2m2mPriv instantiated by the encoder/decoder.
103  *
104  * @returns 0
105  *
106  */
108 
109 /**
110  * Reinitializes the V4L2m2mContext when the driver cannot continue processing
111  * with the capture parameters.
112  *
113  * @param[in] ctx The V4L2m2mContext instantiated by the encoder/decoder.
114  *
115  * @returns 0 in case of success, negative number otherwise
116  */
118 
119 /**
120  * Reinitializes the V4L2m2mContext when the driver cannot continue processing
121  * with the any of the current V4L2Contexts (ie, changes in output and capture).
122  *
123  * @param[in] ctx The V4L2m2mContext instantiated by the encoder/decoder.
124  *
125  * @returns 0 in case of success, negative number otherwise
126  */
128 
129 #endif /* AVCODEC_V4L2_M2M_H */
AVCodecContext * avctx
Definition: v4l2_m2m.h:52
void * priv
Definition: v4l2_m2m.h:65
#define sem_t
Definition: semaphore.h:25
V4L2m2mContext * context
Definition: v4l2_m2m.h:71
int ff_v4l2_m2m_create_context(V4L2m2mPriv *priv, V4L2m2mContext **s)
Allocate a new context and references for a V4L2 M2M instance.
Definition: v4l2_m2m.c:397
char devname[PATH_MAX]
Definition: v4l2_m2m.h:44
int num_output_buffers
Definition: v4l2_m2m.h:74
AVFormatContext * ctx
Definition: movenc.c:48
#define s(width, name)
Definition: cbs_vp9.c:257
V4L2Context capture
Definition: v4l2_m2m.h:48
Libavcodec external API header.
atomic_uint refcount
Definition: v4l2_m2m.h:54
main external API structure.
Definition: avcodec.h:1570
Describe the class of an AVClass context structure.
Definition: log.h:67
intptr_t atomic_uint
Definition: stdatomic.h:56
AVPacket buf_pkt
Definition: v4l2_m2m.h:59
V4L2Context output
Definition: v4l2_m2m.h:49
A reference to a data buffer.
Definition: buffer.h:81
int ff_v4l2_m2m_codec_full_reinit(V4L2m2mContext *ctx)
Reinitializes the V4L2m2mContext when the driver cannot continue processing with the any of the curre...
Definition: v4l2_m2m.c:248
int num_capture_buffers
Definition: v4l2_m2m.h:75
AVBufferRef * self_ref
Definition: v4l2_m2m.h:62
int ff_v4l2_m2m_codec_end(V4L2m2mPriv *priv)
Releases all the codec resources if all AVBufferRefs have been returned to the ctx.
Definition: v4l2_m2m.c:336
AVBufferRef * context_ref
Definition: v4l2_m2m.h:72
sem_t refsync
Definition: v4l2_m2m.h:53
This structure stores compressed data.
Definition: avcodec.h:1459
int ff_v4l2_m2m_codec_init(V4L2m2mPriv *priv)
Probes the video nodes looking for the required codec capabilities.
Definition: v4l2_m2m.c:357
int ff_v4l2_m2m_codec_reinit(V4L2m2mContext *ctx)
Reinitializes the V4L2m2mContext when the driver cannot continue processing with the capture paramete...
Definition: v4l2_m2m.c:205