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/
34 #include <sys/ioctl.h>
39 #include "libavutil/log.h"
40 #include "libavutil/mem.h"
41 #include "libavutil/opt.h"
42 #include "libavutil/time.h"
43 #include "libavutil/parseutils.h"
44 #include "libavutil/pixdesc.h"
46 #include "libavformat/internal.h"
48 struct rgb_pixfmt_map_entry {
50 int red_offset, green_offset, blue_offset, alpha_offset;
51 enum AVPixelFormat pixfmt;
54 static const struct rgb_pixfmt_map_entry rgb_pixfmt_map[] = {
55 // bpp, red_offset, green_offset, blue_offset, alpha_offset, pixfmt
56 { 32, 0, 8, 16, 24, AV_PIX_FMT_RGBA },
57 { 32, 16, 8, 0, 24, AV_PIX_FMT_BGRA },
58 { 32, 8, 16, 24, 0, AV_PIX_FMT_ARGB },
59 { 32, 3, 2, 8, 0, AV_PIX_FMT_ABGR },
60 { 24, 0, 8, 16, 0, AV_PIX_FMT_RGB24 },
61 { 24, 16, 8, 0, 0, AV_PIX_FMT_BGR24 },
64 static enum AVPixelFormat get_pixfmt_from_fb_varinfo(struct fb_var_screeninfo *varinfo)
68 for (i = 0; i < FF_ARRAY_ELEMS(rgb_pixfmt_map); i++) {
69 const struct rgb_pixfmt_map_entry *entry = &rgb_pixfmt_map[i];
70 if (entry->bits_per_pixel == varinfo->bits_per_pixel &&
71 entry->red_offset == varinfo->red.offset &&
72 entry->green_offset == varinfo->green.offset &&
73 entry->blue_offset == varinfo->blue.offset)
77 return AV_PIX_FMT_NONE;
81 AVClass *class; ///< class for private options
82 int frame_size; ///< size in bytes of a grabbed frame
83 AVRational framerate_q; ///< framerate
84 char *framerate; ///< framerate string set by a private option
85 int64_t time_frame; ///< time for the next frame to output (in 1/1000000 units)
87 int fd; ///< framebuffer device file descriptor
88 int width, height; ///< assumed frame resolution
89 int frame_linesize; ///< linesize of the output frame, it is assumed to be constant
92 struct fb_var_screeninfo varinfo; ///< variable info;
93 struct fb_fix_screeninfo fixinfo; ///< fixed info;
95 uint8_t *data; ///< framebuffer data
98 static av_cold int fbdev_read_header(AVFormatContext *avctx)
100 FBDevContext *fbdev = avctx->priv_data;
102 enum AVPixelFormat pix_fmt;
103 int ret, flags = O_RDONLY;
105 ret = av_parse_video_rate(&fbdev->framerate_q, fbdev->framerate);
107 av_log(avctx, AV_LOG_ERROR, "Could not parse framerate '%s'.\n", fbdev->framerate);
111 if (!(st = avformat_new_stream(avctx, NULL)))
112 return AVERROR(ENOMEM);
113 avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in microseconds */
115 /* NONBLOCK is ignored by the fbdev driver, only set for consistency */
116 if (avctx->flags & AVFMT_FLAG_NONBLOCK)
119 if ((fbdev->fd = open(avctx->filename, flags)) == -1) {
120 ret = AVERROR(errno);
121 av_log(avctx, AV_LOG_ERROR,
122 "Could not open framebuffer device '%s': %s\n",
123 avctx->filename, strerror(ret));
127 if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
128 ret = AVERROR(errno);
129 av_log(avctx, AV_LOG_ERROR,
130 "FBIOGET_VSCREENINFO: %s\n", strerror(errno));
134 if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) {
135 ret = AVERROR(errno);
136 av_log(avctx, AV_LOG_ERROR,
137 "FBIOGET_FSCREENINFO: %s\n", strerror(errno));
141 pix_fmt = get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
142 if (pix_fmt == AV_PIX_FMT_NONE) {
143 ret = AVERROR(EINVAL);
144 av_log(avctx, AV_LOG_ERROR,
145 "Framebuffer pixel format not supported.\n");
149 fbdev->width = fbdev->varinfo.xres;
150 fbdev->height = fbdev->varinfo.yres;
151 fbdev->bytes_per_pixel = (fbdev->varinfo.bits_per_pixel + 7) >> 3;
152 fbdev->frame_linesize = fbdev->width * fbdev->bytes_per_pixel;
153 fbdev->frame_size = fbdev->frame_linesize * fbdev->height;
154 fbdev->time_frame = AV_NOPTS_VALUE;
155 fbdev->data = mmap(NULL, fbdev->fixinfo.smem_len, PROT_READ, MAP_SHARED, fbdev->fd, 0);
156 if (fbdev->data == MAP_FAILED) {
157 ret = AVERROR(errno);
158 av_log(avctx, AV_LOG_ERROR, "Error in mmap(): %s\n", strerror(errno));
162 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
163 st->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
164 st->codec->width = fbdev->width;
165 st->codec->height = fbdev->height;
166 st->codec->pix_fmt = pix_fmt;
167 st->codec->time_base = av_inv_q(fbdev->framerate_q);
168 st->codec->bit_rate =
169 fbdev->width * fbdev->height * fbdev->bytes_per_pixel * av_q2d(fbdev->framerate_q) * 8;
171 av_log(avctx, AV_LOG_INFO,
172 "w:%d h:%d bpp:%d pixfmt:%s fps:%d/%d bit_rate:%d\n",
173 fbdev->width, fbdev->height, fbdev->varinfo.bits_per_pixel,
174 av_get_pix_fmt_name(pix_fmt),
175 fbdev->framerate_q.num, fbdev->framerate_q.den,
176 st->codec->bit_rate);
184 static int fbdev_read_packet(AVFormatContext *avctx, AVPacket *pkt)
186 FBDevContext *fbdev = avctx->priv_data;
187 int64_t curtime, delay;
192 if (fbdev->time_frame == AV_NOPTS_VALUE)
193 fbdev->time_frame = av_gettime();
195 /* wait based on the frame rate */
197 curtime = av_gettime();
198 delay = fbdev->time_frame - curtime;
200 "time_frame:%"PRId64" curtime:%"PRId64" delay:%"PRId64"\n",
201 fbdev->time_frame, curtime, delay);
203 fbdev->time_frame += INT64_C(1000000) / av_q2d(fbdev->framerate_q);
206 if (avctx->flags & AVFMT_FLAG_NONBLOCK)
207 return AVERROR(EAGAIN);
208 ts.tv_sec = delay / 1000000;
209 ts.tv_nsec = (delay % 1000000) * 1000;
210 while (nanosleep(&ts, &ts) < 0 && errno == EINTR);
213 if ((ret = av_new_packet(pkt, fbdev->frame_size)) < 0)
216 /* refresh fbdev->varinfo, visible data position may change at each call */
217 if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0)
218 av_log(avctx, AV_LOG_WARNING,
219 "Error refreshing variable info: %s\n", strerror(errno));
223 /* compute visible data offset */
224 pin = fbdev->data + fbdev->bytes_per_pixel * fbdev->varinfo.xoffset +
225 fbdev->varinfo.yoffset * fbdev->fixinfo.line_length;
228 for (i = 0; i < fbdev->height; i++) {
229 memcpy(pout, pin, fbdev->frame_linesize);
230 pin += fbdev->fixinfo.line_length;
231 pout += fbdev->frame_linesize;
234 return fbdev->frame_size;
237 static av_cold int fbdev_read_close(AVFormatContext *avctx)
239 FBDevContext *fbdev = avctx->priv_data;
241 munmap(fbdev->data, fbdev->frame_size);
247 #define OFFSET(x) offsetof(FBDevContext, x)
248 #define DEC AV_OPT_FLAG_DECODING_PARAM
249 static const AVOption options[] = {
250 { "framerate","", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = "25"}, 0, 0, DEC },
254 static const AVClass fbdev_class = {
255 .class_name = "fbdev indev",
256 .item_name = av_default_item_name,
258 .version = LIBAVUTIL_VERSION_INT,
261 AVInputFormat ff_fbdev_demuxer = {
263 .long_name = NULL_IF_CONFIG_SMALL("Linux framebuffer"),
264 .priv_data_size = sizeof(FBDevContext),
265 .read_header = fbdev_read_header,
266 .read_packet = fbdev_read_packet,
267 .read_close = fbdev_read_close,
268 .flags = AVFMT_NOFILE,
269 .priv_class = &fbdev_class,