2 * Copyright (c) 2011 Stefano Sabatini
3 * Copyright (c) 2009 Giliard B. de Freitas <giliarde@gmail.com>
4 * Copyright (C) 2002 Gunnar Monell <gmo@linux.nu>
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 * Linux framebuffer input device,
26 * inspired by code from fbgrab.c by Gunnar Monell.
27 * @see http://linux-fbdev.sourceforge.net/
32 #include <sys/ioctl.h>
37 #include "libavutil/internal.h"
38 #include "libavutil/log.h"
39 #include "libavutil/mem.h"
40 #include "libavutil/opt.h"
41 #include "libavutil/time.h"
42 #include "libavutil/parseutils.h"
43 #include "libavutil/pixdesc.h"
44 #include "libavformat/internal.h"
46 #include "fbdev_common.h"
48 typedef struct FBDevContext {
49 AVClass *class; ///< class for private options
50 int frame_size; ///< size in bytes of a grabbed frame
51 AVRational framerate_q; ///< framerate
52 int64_t time_frame; ///< time for the next frame to output (in 1/1000000 units)
54 int fd; ///< framebuffer device file descriptor
55 int width, height; ///< assumed frame resolution
56 int frame_linesize; ///< linesize of the output frame, it is assumed to be constant
59 struct fb_var_screeninfo varinfo; ///< variable info;
60 struct fb_fix_screeninfo fixinfo; ///< fixed info;
62 uint8_t *data; ///< framebuffer data
65 static av_cold int fbdev_read_header(AVFormatContext *avctx)
67 FBDevContext *fbdev = avctx->priv_data;
69 enum AVPixelFormat pix_fmt;
70 int ret, flags = O_RDONLY;
73 if (!(st = avformat_new_stream(avctx, NULL)))
74 return AVERROR(ENOMEM);
75 avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in microseconds */
77 /* NONBLOCK is ignored by the fbdev driver, only set for consistency */
78 if (avctx->flags & AVFMT_FLAG_NONBLOCK)
81 if (avctx->filename[0])
82 device = avctx->filename;
84 device = ff_fbdev_default_device();
86 if ((fbdev->fd = avpriv_open(device, flags)) == -1) {
88 av_log(avctx, AV_LOG_ERROR,
89 "Could not open framebuffer device '%s': %s\n",
90 device, av_err2str(ret));
94 if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
96 av_log(avctx, AV_LOG_ERROR,
97 "FBIOGET_VSCREENINFO: %s\n", av_err2str(ret));
101 if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) {
102 ret = AVERROR(errno);
103 av_log(avctx, AV_LOG_ERROR,
104 "FBIOGET_FSCREENINFO: %s\n", av_err2str(ret));
108 pix_fmt = ff_get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
109 if (pix_fmt == AV_PIX_FMT_NONE) {
110 ret = AVERROR(EINVAL);
111 av_log(avctx, AV_LOG_ERROR,
112 "Framebuffer pixel format not supported.\n");
116 fbdev->width = fbdev->varinfo.xres;
117 fbdev->height = fbdev->varinfo.yres;
118 fbdev->bytes_per_pixel = (fbdev->varinfo.bits_per_pixel + 7) >> 3;
119 fbdev->frame_linesize = fbdev->width * fbdev->bytes_per_pixel;
120 fbdev->frame_size = fbdev->frame_linesize * fbdev->height;
121 fbdev->time_frame = AV_NOPTS_VALUE;
122 fbdev->data = mmap(NULL, fbdev->fixinfo.smem_len, PROT_READ, MAP_SHARED, fbdev->fd, 0);
123 if (fbdev->data == MAP_FAILED) {
124 ret = AVERROR(errno);
125 av_log(avctx, AV_LOG_ERROR, "Error in mmap(): %s\n", av_err2str(ret));
129 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
130 st->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
131 st->codec->width = fbdev->width;
132 st->codec->height = fbdev->height;
133 st->codec->pix_fmt = pix_fmt;
134 st->codec->time_base = av_inv_q(fbdev->framerate_q);
135 st->codec->bit_rate =
136 fbdev->width * fbdev->height * fbdev->bytes_per_pixel * av_q2d(fbdev->framerate_q) * 8;
138 av_log(avctx, AV_LOG_INFO,
139 "w:%d h:%d bpp:%d pixfmt:%s fps:%d/%d bit_rate:%d\n",
140 fbdev->width, fbdev->height, fbdev->varinfo.bits_per_pixel,
141 av_get_pix_fmt_name(pix_fmt),
142 fbdev->framerate_q.num, fbdev->framerate_q.den,
143 st->codec->bit_rate);
151 static int fbdev_read_packet(AVFormatContext *avctx, AVPacket *pkt)
153 FBDevContext *fbdev = avctx->priv_data;
154 int64_t curtime, delay;
159 if (fbdev->time_frame == AV_NOPTS_VALUE)
160 fbdev->time_frame = av_gettime();
162 /* wait based on the frame rate */
164 curtime = av_gettime();
165 delay = fbdev->time_frame - curtime;
167 "time_frame:%"PRId64" curtime:%"PRId64" delay:%"PRId64"\n",
168 fbdev->time_frame, curtime, delay);
170 fbdev->time_frame += INT64_C(1000000) / av_q2d(fbdev->framerate_q);
173 if (avctx->flags & AVFMT_FLAG_NONBLOCK)
174 return AVERROR(EAGAIN);
175 ts.tv_sec = delay / 1000000;
176 ts.tv_nsec = (delay % 1000000) * 1000;
177 while (nanosleep(&ts, &ts) < 0 && errno == EINTR);
180 if ((ret = av_new_packet(pkt, fbdev->frame_size)) < 0)
183 /* refresh fbdev->varinfo, visible data position may change at each call */
184 if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0)
185 av_log(avctx, AV_LOG_WARNING,
186 "Error refreshing variable info: %s\n", av_err2str(ret));
190 /* compute visible data offset */
191 pin = fbdev->data + fbdev->bytes_per_pixel * fbdev->varinfo.xoffset +
192 fbdev->varinfo.yoffset * fbdev->fixinfo.line_length;
195 for (i = 0; i < fbdev->height; i++) {
196 memcpy(pout, pin, fbdev->frame_linesize);
197 pin += fbdev->fixinfo.line_length;
198 pout += fbdev->frame_linesize;
201 return fbdev->frame_size;
204 static av_cold int fbdev_read_close(AVFormatContext *avctx)
206 FBDevContext *fbdev = avctx->priv_data;
208 munmap(fbdev->data, fbdev->fixinfo.smem_len);
214 static int fbdev_get_device_list(AVFormatContext *s, AVDeviceInfoList *device_list)
216 return ff_fbdev_get_device_list(device_list);
219 #define OFFSET(x) offsetof(FBDevContext, x)
220 #define DEC AV_OPT_FLAG_DECODING_PARAM
221 static const AVOption options[] = {
222 { "framerate","", OFFSET(framerate_q), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, 0, DEC },
226 static const AVClass fbdev_class = {
227 .class_name = "fbdev indev",
228 .item_name = av_default_item_name,
230 .version = LIBAVUTIL_VERSION_INT,
231 .category = AV_CLASS_CATEGORY_DEVICE_VIDEO_INPUT,
234 AVInputFormat ff_fbdev_demuxer = {
236 .long_name = NULL_IF_CONFIG_SMALL("Linux framebuffer"),
237 .priv_data_size = sizeof(FBDevContext),
238 .read_header = fbdev_read_header,
239 .read_packet = fbdev_read_packet,
240 .read_close = fbdev_read_close,
241 .get_device_list = fbdev_get_device_list,
242 .flags = AVFMT_NOFILE,
243 .priv_class = &fbdev_class,