1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
|
/*
* Copyright (c) 2011 Stefano Sabatini
* Copyright (c) 2009 Giliard B. de Freitas <giliarde@gmail.com>
* Copyright (C) 2002 Gunnar Monell <gmo@linux.nu>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Linux framebuffer input device,
* inspired by code from fbgrab.c by Gunnar Monell.
* @see http://linux-fbdev.sourceforge.net/
*/
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <time.h>
#include <linux/fb.h>
#include "libavutil/file_open.h"
#include "libavutil/internal.h"
#include "libavutil/log.h"
#include "libavutil/opt.h"
#include "libavutil/time.h"
#include "libavutil/parseutils.h"
#include "libavutil/pixdesc.h"
#include "libavformat/demux.h"
#include "libavformat/internal.h"
#include "avdevice.h"
#include "fbdev_common.h"
typedef struct FBDevContext {
AVClass *class; ///< class for private options
int frame_size; ///< size in bytes of a grabbed frame
AVRational framerate_q; ///< framerate
int64_t time_frame; ///< time for the next frame to output (in 1/1000000 units)
int fd; ///< framebuffer device file descriptor
int width, height; ///< assumed frame resolution
int frame_linesize; ///< linesize of the output frame, it is assumed to be constant
int bytes_per_pixel;
struct fb_var_screeninfo varinfo; ///< variable info;
struct fb_fix_screeninfo fixinfo; ///< fixed info;
uint8_t *data; ///< framebuffer data
} FBDevContext;
static av_cold int fbdev_read_header(AVFormatContext *avctx)
{
FBDevContext *fbdev = avctx->priv_data;
AVStream *st = NULL;
enum AVPixelFormat pix_fmt;
int ret, flags = O_RDONLY;
const char* device;
if (!(st = avformat_new_stream(avctx, NULL)))
return AVERROR(ENOMEM);
avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in microseconds */
/* NONBLOCK is ignored by the fbdev driver, only set for consistency */
if (avctx->flags & AVFMT_FLAG_NONBLOCK)
flags |= O_NONBLOCK;
if (avctx->url[0])
device = avctx->url;
else
device = ff_fbdev_default_device();
if ((fbdev->fd = avpriv_open(device, flags)) == -1) {
ret = AVERROR(errno);
av_log(avctx, AV_LOG_ERROR,
"Could not open framebuffer device '%s': %s\n",
device, av_err2str(ret));
return ret;
}
if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
ret = AVERROR(errno);
av_log(avctx, AV_LOG_ERROR,
"FBIOGET_VSCREENINFO: %s\n", av_err2str(ret));
goto fail;
}
if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) {
ret = AVERROR(errno);
av_log(avctx, AV_LOG_ERROR,
"FBIOGET_FSCREENINFO: %s\n", av_err2str(ret));
goto fail;
}
pix_fmt = ff_get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
if (pix_fmt == AV_PIX_FMT_NONE) {
ret = AVERROR(EINVAL);
av_log(avctx, AV_LOG_ERROR,
"Framebuffer pixel format not supported.\n");
goto fail;
}
fbdev->width = fbdev->varinfo.xres;
fbdev->height = fbdev->varinfo.yres;
fbdev->bytes_per_pixel = (fbdev->varinfo.bits_per_pixel + 7) >> 3;
fbdev->frame_linesize = fbdev->width * fbdev->bytes_per_pixel;
fbdev->frame_size = fbdev->frame_linesize * fbdev->height;
fbdev->time_frame = AV_NOPTS_VALUE;
fbdev->data = mmap(NULL, fbdev->fixinfo.smem_len, PROT_READ, MAP_SHARED, fbdev->fd, 0);
if (fbdev->data == MAP_FAILED) {
ret = AVERROR(errno);
av_log(avctx, AV_LOG_ERROR, "Error in mmap(): %s\n", av_err2str(ret));
goto fail;
}
st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
st->codecpar->codec_id = AV_CODEC_ID_RAWVIDEO;
st->codecpar->width = fbdev->width;
st->codecpar->height = fbdev->height;
st->codecpar->format = pix_fmt;
st->avg_frame_rate = fbdev->framerate_q;
st->codecpar->bit_rate =
fbdev->width * fbdev->height * fbdev->bytes_per_pixel * av_q2d(fbdev->framerate_q) * 8;
av_log(avctx, AV_LOG_INFO,
"w:%d h:%d bpp:%d pixfmt:%s fps:%d/%d bit_rate:%"PRId64"\n",
fbdev->width, fbdev->height, fbdev->varinfo.bits_per_pixel,
av_get_pix_fmt_name(pix_fmt),
fbdev->framerate_q.num, fbdev->framerate_q.den,
st->codecpar->bit_rate);
return 0;
fail:
close(fbdev->fd);
return ret;
}
static int fbdev_read_packet(AVFormatContext *avctx, AVPacket *pkt)
{
FBDevContext *fbdev = avctx->priv_data;
int64_t curtime, delay;
struct timespec ts;
int i, ret;
uint8_t *pin, *pout;
if (fbdev->time_frame == AV_NOPTS_VALUE)
fbdev->time_frame = av_gettime_relative();
/* wait based on the frame rate */
while (1) {
curtime = av_gettime_relative();
delay = fbdev->time_frame - curtime;
av_log(avctx, AV_LOG_TRACE,
"time_frame:%"PRId64" curtime:%"PRId64" delay:%"PRId64"\n",
fbdev->time_frame, curtime, delay);
if (delay <= 0) {
fbdev->time_frame += INT64_C(1000000) / av_q2d(fbdev->framerate_q);
break;
}
if (avctx->flags & AVFMT_FLAG_NONBLOCK)
return AVERROR(EAGAIN);
ts.tv_sec = delay / 1000000;
ts.tv_nsec = (delay % 1000000) * 1000;
while (nanosleep(&ts, &ts) < 0 && errno == EINTR);
}
if ((ret = av_new_packet(pkt, fbdev->frame_size)) < 0)
return ret;
/* refresh fbdev->varinfo, visible data position may change at each call */
if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
av_log(avctx, AV_LOG_WARNING,
"Error refreshing variable info: %s\n", av_err2str(AVERROR(errno)));
}
pkt->pts = av_gettime();
/* compute visible data offset */
pin = fbdev->data + fbdev->bytes_per_pixel * fbdev->varinfo.xoffset +
fbdev->varinfo.yoffset * fbdev->fixinfo.line_length;
pout = pkt->data;
for (i = 0; i < fbdev->height; i++) {
memcpy(pout, pin, fbdev->frame_linesize);
pin += fbdev->fixinfo.line_length;
pout += fbdev->frame_linesize;
}
return fbdev->frame_size;
}
static av_cold int fbdev_read_close(AVFormatContext *avctx)
{
FBDevContext *fbdev = avctx->priv_data;
munmap(fbdev->data, fbdev->fixinfo.smem_len);
close(fbdev->fd);
return 0;
}
static int fbdev_get_device_list(AVFormatContext *s, AVDeviceInfoList *device_list)
{
return ff_fbdev_get_device_list(device_list);
}
#define OFFSET(x) offsetof(FBDevContext, x)
#define DEC AV_OPT_FLAG_DECODING_PARAM
static const AVOption options[] = {
{ "framerate","", OFFSET(framerate_q), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, DEC },
{ NULL },
};
static const AVClass fbdev_class = {
.class_name = "fbdev indev",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
.category = AV_CLASS_CATEGORY_DEVICE_VIDEO_INPUT,
};
const FFInputFormat ff_fbdev_demuxer = {
.p.name = "fbdev",
.p.long_name = NULL_IF_CONFIG_SMALL("Linux framebuffer"),
.p.flags = AVFMT_NOFILE,
.p.priv_class = &fbdev_class,
.priv_data_size = sizeof(FBDevContext),
.read_header = fbdev_read_header,
.read_packet = fbdev_read_packet,
.read_close = fbdev_read_close,
.get_device_list = fbdev_get_device_list,
};
|
