2 * Copyright (c) 2013 Clément Bœsch
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 #include "v4l2-common.h"
29 static av_cold
int write_header(AVFormatContext
*s1
)
31 int res
= 0, flags
= O_RDWR
;
32 struct v4l2_format fmt
= {
33 .type
= V4L2_BUF_TYPE_VIDEO_OUTPUT
35 V4L2Context
*s
= s1
->priv_data
;
36 AVCodecContext
*enc_ctx
;
39 if (s1
->flags
& AVFMT_FLAG_NONBLOCK
)
42 s
->fd
= open(s1
->filename
, flags
);
45 av_log(s1
, AV_LOG_ERROR
, "Unable to open V4L2 device '%s'\n", s1
->filename
);
49 if (s1
->nb_streams
!= 1 ||
50 s1
->streams
[0]->codec
->codec_type
!= AVMEDIA_TYPE_VIDEO
||
51 s1
->streams
[0]->codec
->codec_id
!= AV_CODEC_ID_RAWVIDEO
) {
52 av_log(s1
, AV_LOG_ERROR
,
53 "V4L2 output device supports only a single raw video stream\n");
54 return AVERROR(EINVAL
);
57 enc_ctx
= s1
->streams
[0]->codec
;
59 v4l2_pixfmt
= avpriv_fmt_ff2v4l(enc_ctx
->pix_fmt
, AV_CODEC_ID_RAWVIDEO
);
60 if (!v4l2_pixfmt
) { // XXX: try to force them one by one?
61 av_log(s1
, AV_LOG_ERROR
, "Unknown V4L2 pixel format equivalent for %s\n",
62 av_get_pix_fmt_name(enc_ctx
->pix_fmt
));
63 return AVERROR(EINVAL
);
66 if (ioctl(s
->fd
, VIDIOC_G_FMT
, &fmt
) < 0) {
68 av_log(s1
, AV_LOG_ERROR
, "ioctl(VIDIOC_G_FMT): %s\n", av_err2str(res
));
72 fmt
.fmt
.pix
.width
= enc_ctx
->width
;
73 fmt
.fmt
.pix
.height
= enc_ctx
->height
;
74 fmt
.fmt
.pix
.pixelformat
= v4l2_pixfmt
;
75 fmt
.fmt
.pix
.sizeimage
= av_image_get_buffer_size(enc_ctx
->pix_fmt
, enc_ctx
->width
, enc_ctx
->height
, 1);
77 if (ioctl(s
->fd
, VIDIOC_S_FMT
, &fmt
) < 0) {
79 av_log(s1
, AV_LOG_ERROR
, "ioctl(VIDIOC_S_FMT): %s\n", av_err2str(res
));
86 static int write_packet(AVFormatContext
*s1
, AVPacket
*pkt
)
88 const V4L2Context
*s
= s1
->priv_data
;
89 if (write(s
->fd
, pkt
->data
, pkt
->size
) == -1)
90 return AVERROR(errno
);
94 static int write_trailer(AVFormatContext
*s1
)
96 const V4L2Context
*s
= s1
->priv_data
;
101 static const AVClass v4l2_class
= {
102 .class_name
= "V4L2 outdev",
103 .item_name
= av_default_item_name
,
104 .version
= LIBAVUTIL_VERSION_INT
,
105 .category
= AV_CLASS_CATEGORY_DEVICE_VIDEO_OUTPUT
,
108 AVOutputFormat ff_v4l2_muxer
= {
110 .long_name
= NULL_IF_CONFIG_SMALL("Video4Linux2 output device"),
111 .priv_data_size
= sizeof(V4L2Context
),
112 .audio_codec
= AV_CODEC_ID_NONE
,
113 .video_codec
= AV_CODEC_ID_RAWVIDEO
,
114 .write_header
= write_header
,
115 .write_packet
= write_packet
,
116 .write_trailer
= write_trailer
,
117 .flags
= AVFMT_NOFILE
,
118 .priv_class
= &v4l2_class
,