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/log.h"
38 #include "libavutil/mem.h"
39 #include "libavutil/opt.h"
40 #include "libavutil/time.h"
41 #include "libavutil/parseutils.h"
42 #include "libavutil/pixdesc.h"
44 #include "libavformat/internal.h"
46 struct rgb_pixfmt_map_entry {
48 int red_offset, green_offset, blue_offset, alpha_offset;
49 enum AVPixelFormat pixfmt;
52 static const struct rgb_pixfmt_map_entry rgb_pixfmt_map[] = {
53 // bpp, red_offset, green_offset, blue_offset, alpha_offset, pixfmt
54 { 32, 0, 8, 16, 24, AV_PIX_FMT_RGBA },
55 { 32, 16, 8, 0, 24, AV_PIX_FMT_BGRA },
56 { 32, 8, 16, 24, 0, AV_PIX_FMT_ARGB },
57 { 32, 3, 2, 8, 0, AV_PIX_FMT_ABGR },
58 { 24, 0, 8, 16, 0, AV_PIX_FMT_RGB24 },
59 { 24, 16, 8, 0, 0, AV_PIX_FMT_BGR24 },
60 { 16, 11, 5, 0, 16, AV_PIX_FMT_RGB565 },
63 static enum AVPixelFormat get_pixfmt_from_fb_varinfo(struct fb_var_screeninfo *varinfo)
67 for (i = 0; i < FF_ARRAY_ELEMS(rgb_pixfmt_map); i++) {
68 const 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)
76 return AV_PIX_FMT_NONE;
80 AVClass *class; ///< class for private options
81 int frame_size; ///< size in bytes of a grabbed frame
82 AVRational framerate_q; ///< framerate
83 int64_t time_frame; ///< time for the next frame to output (in 1/1000000 units)
85 int fd; ///< framebuffer device file descriptor
86 int width, height; ///< assumed frame resolution
87 int frame_linesize; ///< linesize of the output frame, it is assumed to be constant
90 struct fb_var_screeninfo varinfo; ///< variable info;
91 struct fb_fix_screeninfo fixinfo; ///< fixed info;
93 uint8_t *data; ///< framebuffer data
96 static av_cold int fbdev_read_header(AVFormatContext *avctx)
98 FBDevContext *fbdev = avctx->priv_data;
100 enum AVPixelFormat pix_fmt;
101 int ret, flags = O_RDONLY;
103 if (!(st = avformat_new_stream(avctx, NULL)))
104 return AVERROR(ENOMEM);
105 avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in microseconds */
107 /* NONBLOCK is ignored by the fbdev driver, only set for consistency */
108 if (avctx->flags & AVFMT_FLAG_NONBLOCK)
111 if ((fbdev->fd = open(avctx->filename, flags)) == -1) {
112 ret = AVERROR(errno);
113 av_log(avctx, AV_LOG_ERROR,
114 "Could not open framebuffer device '%s': %s\n",
115 avctx->filename, strerror(ret));
119 if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
120 ret = AVERROR(errno);
121 av_log(avctx, AV_LOG_ERROR,
122 "FBIOGET_VSCREENINFO: %s\n", strerror(errno));
126 if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) {
127 ret = AVERROR(errno);
128 av_log(avctx, AV_LOG_ERROR,
129 "FBIOGET_FSCREENINFO: %s\n", strerror(errno));
133 pix_fmt = get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
134 if (pix_fmt == AV_PIX_FMT_NONE) {
135 ret = AVERROR(EINVAL);
136 av_log(avctx, AV_LOG_ERROR,
137 "Framebuffer pixel format not supported.\n");
141 fbdev->width = fbdev->varinfo.xres;
142 fbdev->height = fbdev->varinfo.yres;
143 fbdev->bytes_per_pixel = (fbdev->varinfo.bits_per_pixel + 7) >> 3;
144 fbdev->frame_linesize = fbdev->width * fbdev->bytes_per_pixel;
145 fbdev->frame_size = fbdev->frame_linesize * fbdev->height;
146 fbdev->time_frame = AV_NOPTS_VALUE;
147 fbdev->data = mmap(NULL, fbdev->fixinfo.smem_len, PROT_READ, MAP_SHARED, fbdev->fd, 0);
148 if (fbdev->data == MAP_FAILED) {
149 ret = AVERROR(errno);
150 av_log(avctx, AV_LOG_ERROR, "Error in mmap(): %s\n", strerror(errno));
154 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
155 st->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
156 st->codec->width = fbdev->width;
157 st->codec->height = fbdev->height;
158 st->codec->pix_fmt = pix_fmt;
159 st->codec->time_base = av_inv_q(fbdev->framerate_q);
160 st->codec->bit_rate =
161 fbdev->width * fbdev->height * fbdev->bytes_per_pixel * av_q2d(fbdev->framerate_q) * 8;
163 av_log(avctx, AV_LOG_INFO,
164 "w:%d h:%d bpp:%d pixfmt:%s fps:%d/%d bit_rate:%d\n",
165 fbdev->width, fbdev->height, fbdev->varinfo.bits_per_pixel,
166 av_get_pix_fmt_name(pix_fmt),
167 fbdev->framerate_q.num, fbdev->framerate_q.den,
168 st->codec->bit_rate);
176 static int fbdev_read_packet(AVFormatContext *avctx, AVPacket *pkt)
178 FBDevContext *fbdev = avctx->priv_data;
179 int64_t curtime, delay;
184 if (fbdev->time_frame == AV_NOPTS_VALUE)
185 fbdev->time_frame = av_gettime();
187 /* wait based on the frame rate */
189 curtime = av_gettime();
190 delay = fbdev->time_frame - curtime;
192 "time_frame:%"PRId64" curtime:%"PRId64" delay:%"PRId64"\n",
193 fbdev->time_frame, curtime, delay);
195 fbdev->time_frame += INT64_C(1000000) / av_q2d(fbdev->framerate_q);
198 if (avctx->flags & AVFMT_FLAG_NONBLOCK)
199 return AVERROR(EAGAIN);
200 ts.tv_sec = delay / 1000000;
201 ts.tv_nsec = (delay % 1000000) * 1000;
202 while (nanosleep(&ts, &ts) < 0 && errno == EINTR);
205 if ((ret = av_new_packet(pkt, fbdev->frame_size)) < 0)
208 /* refresh fbdev->varinfo, visible data position may change at each call */
209 if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0)
210 av_log(avctx, AV_LOG_WARNING,
211 "Error refreshing variable info: %s\n", strerror(errno));
215 /* compute visible data offset */
216 pin = fbdev->data + fbdev->bytes_per_pixel * fbdev->varinfo.xoffset +
217 fbdev->varinfo.yoffset * fbdev->fixinfo.line_length;
220 for (i = 0; i < fbdev->height; i++) {
221 memcpy(pout, pin, fbdev->frame_linesize);
222 pin += fbdev->fixinfo.line_length;
223 pout += fbdev->frame_linesize;
226 return fbdev->frame_size;
229 static av_cold int fbdev_read_close(AVFormatContext *avctx)
231 FBDevContext *fbdev = avctx->priv_data;
233 munmap(fbdev->data, fbdev->frame_size);
239 #define OFFSET(x) offsetof(FBDevContext, x)
240 #define DEC AV_OPT_FLAG_DECODING_PARAM
241 static const AVOption options[] = {
242 { "framerate","", OFFSET(framerate_q), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, 0, DEC },
246 static const AVClass fbdev_class = {
247 .class_name = "fbdev indev",
248 .item_name = av_default_item_name,
250 .version = LIBAVUTIL_VERSION_INT,
253 AVInputFormat ff_fbdev_demuxer = {
255 .long_name = NULL_IF_CONFIG_SMALL("Linux framebuffer"),
256 .priv_data_size = sizeof(FBDevContext),
257 .read_header = fbdev_read_header,
258 .read_packet = fbdev_read_packet,
259 .read_close = fbdev_read_close,
260 .flags = AVFMT_NOFILE,
261 .priv_class = &fbdev_class,