| 1 | /* |
| 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> |
| 5 | * |
| 6 | * This file is part of FFmpeg. |
| 7 | * |
| 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. |
| 12 | * |
| 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. |
| 17 | * |
| 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 |
| 21 | */ |
| 22 | |
| 23 | /** |
| 24 | * @file |
| 25 | * Linux framebuffer input device, |
| 26 | * inspired by code from fbgrab.c by Gunnar Monell. |
| 27 | * @see http://linux-fbdev.sourceforge.net/ |
| 28 | */ |
| 29 | |
| 30 | #include <unistd.h> |
| 31 | #include <fcntl.h> |
| 32 | #include <sys/ioctl.h> |
| 33 | #include <sys/mman.h> |
| 34 | #include <time.h> |
| 35 | #include <linux/fb.h> |
| 36 | |
| 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" |
| 45 | #include "avdevice.h" |
| 46 | #include "fbdev_common.h" |
| 47 | |
| 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) |
| 53 | |
| 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 |
| 57 | int bytes_per_pixel; |
| 58 | |
| 59 | struct fb_var_screeninfo varinfo; ///< variable info; |
| 60 | struct fb_fix_screeninfo fixinfo; ///< fixed info; |
| 61 | |
| 62 | uint8_t *data; ///< framebuffer data |
| 63 | } FBDevContext; |
| 64 | |
| 65 | static av_cold int fbdev_read_header(AVFormatContext *avctx) |
| 66 | { |
| 67 | FBDevContext *fbdev = avctx->priv_data; |
| 68 | AVStream *st = NULL; |
| 69 | enum AVPixelFormat pix_fmt; |
| 70 | int ret, flags = O_RDONLY; |
| 71 | const char* device; |
| 72 | |
| 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 */ |
| 76 | |
| 77 | /* NONBLOCK is ignored by the fbdev driver, only set for consistency */ |
| 78 | if (avctx->flags & AVFMT_FLAG_NONBLOCK) |
| 79 | flags |= O_NONBLOCK; |
| 80 | |
| 81 | if (avctx->filename[0]) |
| 82 | device = avctx->filename; |
| 83 | else |
| 84 | device = ff_fbdev_default_device(); |
| 85 | |
| 86 | if ((fbdev->fd = avpriv_open(device, flags)) == -1) { |
| 87 | ret = AVERROR(errno); |
| 88 | av_log(avctx, AV_LOG_ERROR, |
| 89 | "Could not open framebuffer device '%s': %s\n", |
| 90 | device, av_err2str(ret)); |
| 91 | return ret; |
| 92 | } |
| 93 | |
| 94 | if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) { |
| 95 | ret = AVERROR(errno); |
| 96 | av_log(avctx, AV_LOG_ERROR, |
| 97 | "FBIOGET_VSCREENINFO: %s\n", av_err2str(ret)); |
| 98 | goto fail; |
| 99 | } |
| 100 | |
| 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)); |
| 105 | goto fail; |
| 106 | } |
| 107 | |
| 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"); |
| 113 | goto fail; |
| 114 | } |
| 115 | |
| 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)); |
| 126 | goto fail; |
| 127 | } |
| 128 | |
| 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; |
| 137 | |
| 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); |
| 144 | return 0; |
| 145 | |
| 146 | fail: |
| 147 | close(fbdev->fd); |
| 148 | return ret; |
| 149 | } |
| 150 | |
| 151 | static int fbdev_read_packet(AVFormatContext *avctx, AVPacket *pkt) |
| 152 | { |
| 153 | FBDevContext *fbdev = avctx->priv_data; |
| 154 | int64_t curtime, delay; |
| 155 | struct timespec ts; |
| 156 | int i, ret; |
| 157 | uint8_t *pin, *pout; |
| 158 | |
| 159 | if (fbdev->time_frame == AV_NOPTS_VALUE) |
| 160 | fbdev->time_frame = av_gettime(); |
| 161 | |
| 162 | /* wait based on the frame rate */ |
| 163 | while (1) { |
| 164 | curtime = av_gettime(); |
| 165 | delay = fbdev->time_frame - curtime; |
| 166 | av_dlog(avctx, |
| 167 | "time_frame:%"PRId64" curtime:%"PRId64" delay:%"PRId64"\n", |
| 168 | fbdev->time_frame, curtime, delay); |
| 169 | if (delay <= 0) { |
| 170 | fbdev->time_frame += INT64_C(1000000) / av_q2d(fbdev->framerate_q); |
| 171 | break; |
| 172 | } |
| 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); |
| 178 | } |
| 179 | |
| 180 | if ((ret = av_new_packet(pkt, fbdev->frame_size)) < 0) |
| 181 | return ret; |
| 182 | |
| 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(AVERROR(errno))); |
| 187 | } |
| 188 | |
| 189 | pkt->pts = curtime; |
| 190 | |
| 191 | /* compute visible data offset */ |
| 192 | pin = fbdev->data + fbdev->bytes_per_pixel * fbdev->varinfo.xoffset + |
| 193 | fbdev->varinfo.yoffset * fbdev->fixinfo.line_length; |
| 194 | pout = pkt->data; |
| 195 | |
| 196 | for (i = 0; i < fbdev->height; i++) { |
| 197 | memcpy(pout, pin, fbdev->frame_linesize); |
| 198 | pin += fbdev->fixinfo.line_length; |
| 199 | pout += fbdev->frame_linesize; |
| 200 | } |
| 201 | |
| 202 | return fbdev->frame_size; |
| 203 | } |
| 204 | |
| 205 | static av_cold int fbdev_read_close(AVFormatContext *avctx) |
| 206 | { |
| 207 | FBDevContext *fbdev = avctx->priv_data; |
| 208 | |
| 209 | munmap(fbdev->data, fbdev->fixinfo.smem_len); |
| 210 | close(fbdev->fd); |
| 211 | |
| 212 | return 0; |
| 213 | } |
| 214 | |
| 215 | static int fbdev_get_device_list(AVFormatContext *s, AVDeviceInfoList *device_list) |
| 216 | { |
| 217 | return ff_fbdev_get_device_list(device_list); |
| 218 | } |
| 219 | |
| 220 | #define OFFSET(x) offsetof(FBDevContext, x) |
| 221 | #define DEC AV_OPT_FLAG_DECODING_PARAM |
| 222 | static const AVOption options[] = { |
| 223 | { "framerate","", OFFSET(framerate_q), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, 0, DEC }, |
| 224 | { NULL }, |
| 225 | }; |
| 226 | |
| 227 | static const AVClass fbdev_class = { |
| 228 | .class_name = "fbdev indev", |
| 229 | .item_name = av_default_item_name, |
| 230 | .option = options, |
| 231 | .version = LIBAVUTIL_VERSION_INT, |
| 232 | .category = AV_CLASS_CATEGORY_DEVICE_VIDEO_INPUT, |
| 233 | }; |
| 234 | |
| 235 | AVInputFormat ff_fbdev_demuxer = { |
| 236 | .name = "fbdev", |
| 237 | .long_name = NULL_IF_CONFIG_SMALL("Linux framebuffer"), |
| 238 | .priv_data_size = sizeof(FBDevContext), |
| 239 | .read_header = fbdev_read_header, |
| 240 | .read_packet = fbdev_read_packet, |
| 241 | .read_close = fbdev_read_close, |
| 242 | .get_device_list = fbdev_get_device_list, |
| 243 | .flags = AVFMT_NOFILE, |
| 244 | .priv_class = &fbdev_class, |
| 245 | }; |