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 also http://linux-fbdev.sourceforge.net/.
34 #include <sys/ioctl.h>
40 #include "libavutil/log.h"
41 #include "libavutil/mem.h"
42 #include "libavutil/opt.h"
43 #include "libavutil/parseutils.h"
44 #include "libavutil/pixdesc.h"
47 struct rgb_pixfmt_map_entry {
49 int red_offset, green_offset, blue_offset, alpha_offset;
50 enum PixelFormat pixfmt;
53 static struct rgb_pixfmt_map_entry rgb_pixfmt_map[] = {
54 // bpp, red_offset, green_offset, blue_offset, alpha_offset, pixfmt
55 { 32, 0, 8, 16, 24, PIX_FMT_RGBA },
56 { 32, 16, 8, 0, 24, PIX_FMT_BGRA },
57 { 32, 8, 16, 24, 0, PIX_FMT_ARGB },
58 { 32, 3, 2, 8, 0, PIX_FMT_ABGR },
59 { 24, 0, 8, 16, 0, PIX_FMT_RGB24 },
60 { 24, 16, 8, 0, 0, PIX_FMT_BGR24 },
63 static enum PixelFormat get_pixfmt_from_fb_varinfo(struct fb_var_screeninfo *varinfo)
67 for (i = 0; i < FF_ARRAY_ELEMS(rgb_pixfmt_map); i++) {
68 struct rgb_pixfmt_map_entry *entry = &rgb_pixfmt_map[i];
69 if (entry->bits_per_pixel == varinfo->bits_per_pixel &&
70 entry->red_offset == varinfo->red.offset &&
71 entry->green_offset == varinfo->green.offset &&
72 entry->blue_offset == varinfo->blue.offset)
80 AVClass *class; ///< class for private options
81 int frame_size; ///< size in bytes of a grabbed frame
82 AVRational fps; ///< framerate
83 char *framerate; ///< framerate string set by a private option
84 int64_t time_frame; ///< time for the next frame to output (in 1/1000000 units)
86 int fd; ///< framebuffer device file descriptor
87 int width, heigth; ///< assumed frame resolution
88 int frame_linesize; ///< linesize of the output frame, it is assumed to be constant
91 struct fb_var_screeninfo varinfo; ///< variable info;
92 struct fb_fix_screeninfo fixinfo; ///< fixed info;
94 uint8_t *data; ///< framebuffer data
97 av_cold static int fbdev_read_header(AVFormatContext *avctx,
98 AVFormatParameters *ap)
100 FBDevContext *fbdev = avctx->priv_data;
102 enum PixelFormat pix_fmt;
103 int ret, flags = O_RDONLY;
105 ret = av_parse_video_rate(&fbdev->fps, fbdev->framerate);
106 av_freep(&fbdev->framerate);
108 av_log(avctx, AV_LOG_ERROR, "Couldn't parse framerate.\n");
111 #if FF_API_FORMAT_PARAMETERS
112 if (ap->time_base.num)
113 fbdev->fps = (AVRational){ap->time_base.den, ap->time_base.num};
116 if (!(st = av_new_stream(avctx, 0)))
117 return AVERROR(ENOMEM);
118 av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in microseconds */
120 /* NONBLOCK is ignored by the fbdev driver, only set for consistency */
121 if (avctx->flags & AVFMT_FLAG_NONBLOCK)
124 if ((fbdev->fd = open(avctx->filename, flags)) == -1) {
125 ret = AVERROR(errno);
126 av_log(avctx, AV_LOG_ERROR,
127 "Could not open framebuffer device '%s': %s\n",
128 avctx->filename, strerror(ret));
132 if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
133 ret = AVERROR(errno);
134 av_log(avctx, AV_LOG_ERROR,
135 "FBIOGET_VSCREENINFO: %s\n", strerror(errno));
139 if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) {
140 ret = AVERROR(errno);
141 av_log(avctx, AV_LOG_ERROR,
142 "FBIOGET_FSCREENINFO: %s\n", strerror(errno));
146 pix_fmt = get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
147 if (pix_fmt == PIX_FMT_NONE) {
148 ret = AVERROR(EINVAL);
149 av_log(avctx, AV_LOG_ERROR,
150 "Framebuffer pixel format not supported.\n");
154 fbdev->width = fbdev->varinfo.xres;
155 fbdev->heigth = fbdev->varinfo.yres;
156 fbdev->bytes_per_pixel = (fbdev->varinfo.bits_per_pixel + 7) >> 3;
157 fbdev->frame_linesize = fbdev->width * fbdev->bytes_per_pixel;
158 fbdev->frame_size = fbdev->frame_linesize * fbdev->heigth;
159 fbdev->time_frame = AV_NOPTS_VALUE;
160 fbdev->data = mmap(NULL, fbdev->fixinfo.smem_len, PROT_READ, MAP_SHARED, fbdev->fd, 0);
161 if (fbdev->data == MAP_FAILED) {
162 ret = AVERROR(errno);
163 av_log(avctx, AV_LOG_ERROR, "Error in mmap(): %s\n", strerror(errno));
167 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
168 st->codec->codec_id = CODEC_ID_RAWVIDEO;
169 st->codec->width = fbdev->width;
170 st->codec->height = fbdev->heigth;
171 st->codec->pix_fmt = pix_fmt;
172 st->codec->time_base = (AVRational){fbdev->fps.den, fbdev->fps.num};
173 st->codec->bit_rate =
174 fbdev->width * fbdev->heigth * fbdev->bytes_per_pixel * av_q2d(fbdev->fps) * 8;
176 av_log(avctx, AV_LOG_INFO,
177 "w:%d h:%d bpp:%d pixfmt:%s fps:%d/%d bit_rate:%d\n",
178 fbdev->width, fbdev->heigth, fbdev->varinfo.bits_per_pixel,
179 av_pix_fmt_descriptors[pix_fmt].name,
180 fbdev->fps.num, fbdev->fps.den,
181 st->codec->bit_rate);
189 static int fbdev_read_packet(AVFormatContext *avctx, AVPacket *pkt)
191 FBDevContext *fbdev = avctx->priv_data;
192 int64_t curtime, delay;
197 if (fbdev->time_frame == AV_NOPTS_VALUE)
198 fbdev->time_frame = av_gettime();
200 /* wait based on the frame rate */
202 curtime = av_gettime();
203 delay = fbdev->time_frame - curtime;
205 "time_frame:%"PRId64" curtime:%"PRId64" delay:%"PRId64"\n",
206 fbdev->time_frame, curtime, delay);
208 fbdev->time_frame += INT64_C(1000000) / av_q2d(fbdev->fps);
211 if (avctx->flags & AVFMT_FLAG_NONBLOCK)
212 return AVERROR(EAGAIN);
213 ts.tv_sec = delay / 1000000;
214 ts.tv_nsec = (delay % 1000000) * 1000;
215 while (nanosleep(&ts, &ts) < 0 && errno == EINTR);
218 if ((ret = av_new_packet(pkt, fbdev->frame_size)) < 0)
221 /* refresh fbdev->varinfo, visible data position may change at each call */
222 if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0)
223 av_log(avctx, AV_LOG_WARNING,
224 "Error refreshing variable info: %s\n", strerror(errno));
228 /* compute visible data offset */
229 pin = fbdev->data + fbdev->bytes_per_pixel * fbdev->varinfo.xoffset +
230 fbdev->varinfo.yoffset * fbdev->fixinfo.line_length;
233 for (i = 0; i < fbdev->heigth; i++) {
234 memcpy(pout, pin, fbdev->frame_linesize);
235 pin += fbdev->fixinfo.line_length;
236 pout += fbdev->frame_linesize;
239 return fbdev->frame_size;
242 av_cold static int fbdev_read_close(AVFormatContext *avctx)
244 FBDevContext *fbdev = avctx->priv_data;
246 munmap(fbdev->data, fbdev->frame_size);
252 #define OFFSET(x) offsetof(FBDevContext, x)
253 #define DEC AV_OPT_FLAG_DECODING_PARAM
254 static const AVOption options[] = {
255 { "framerate","", OFFSET(framerate), FF_OPT_TYPE_STRING, {.str = "25"}, 0, 0, DEC },
259 static const AVClass fbdev_class = {
260 .class_name = "fbdev indev",
261 .item_name = av_default_item_name,
263 .version = LIBAVUTIL_VERSION_INT,
266 AVInputFormat ff_fbdev_demuxer = {
268 .long_name = NULL_IF_CONFIG_SMALL("Linux framebuffer"),
269 .priv_data_size = sizeof(FBDevContext),
270 .read_header = fbdev_read_header,
271 .read_packet = fbdev_read_packet,
272 .read_close = fbdev_read_close,
273 .flags = AVFMT_NOFILE,
274 .priv_class = &fbdev_class,