/* * Copyright (c) 2011 Stefano Sabatini * Copyright (c) 2009 Giliard B. de Freitas * Copyright (C) 2002 Gunnar Monell * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * Linux framebuffer input device, * inspired by code from fbgrab.c by Gunnar Monell. * @see http://linux-fbdev.sourceforge.net/ */ #include #include #include #include #include #include #include "libavutil/internal.h" #include "libavutil/log.h" #include "libavutil/mem.h" #include "libavutil/opt.h" #include "libavutil/time.h" #include "libavutil/parseutils.h" #include "libavutil/pixdesc.h" #include "libavformat/avformat.h" #include "libavformat/internal.h" struct rgb_pixfmt_map_entry { int bits_per_pixel; int red_offset, green_offset, blue_offset, alpha_offset; enum AVPixelFormat pixfmt; }; static struct rgb_pixfmt_map_entry rgb_pixfmt_map[] = { // bpp, red_offset, green_offset, blue_offset, alpha_offset, pixfmt { 32, 0, 8, 16, 24, AV_PIX_FMT_RGBA }, { 32, 16, 8, 0, 24, AV_PIX_FMT_BGRA }, { 32, 8, 16, 24, 0, AV_PIX_FMT_ARGB }, { 32, 3, 2, 8, 0, AV_PIX_FMT_ABGR }, { 24, 0, 8, 16, 0, AV_PIX_FMT_RGB24 }, { 24, 16, 8, 0, 0, AV_PIX_FMT_BGR24 }, { 16, 11, 5, 0, 0, AV_PIX_FMT_RGB565 }, }; static enum AVPixelFormat get_pixfmt_from_fb_varinfo(struct fb_var_screeninfo *varinfo) { int i; for (i = 0; i < FF_ARRAY_ELEMS(rgb_pixfmt_map); i++) { struct rgb_pixfmt_map_entry *entry = &rgb_pixfmt_map[i]; if (entry->bits_per_pixel == varinfo->bits_per_pixel && entry->red_offset == varinfo->red.offset && entry->green_offset == varinfo->green.offset && entry->blue_offset == varinfo->blue.offset) return entry->pixfmt; } return AV_PIX_FMT_NONE; } typedef struct FBDevContext { AVClass *class; ///< class for private options int frame_size; ///< size in bytes of a grabbed frame AVRational framerate_q; ///< framerate char *framerate; ///< framerate string set by a private option int64_t time_frame; ///< time for the next frame to output (in 1/1000000 units) int fd; ///< framebuffer device file descriptor int width, height; ///< assumed frame resolution int frame_linesize; ///< linesize of the output frame, it is assumed to be constant int bytes_per_pixel; struct fb_var_screeninfo varinfo; ///< variable info; struct fb_fix_screeninfo fixinfo; ///< fixed info; uint8_t *data; ///< framebuffer data } FBDevContext; static av_cold int fbdev_read_header(AVFormatContext *avctx) { FBDevContext *fbdev = avctx->priv_data; AVStream *st = NULL; enum AVPixelFormat pix_fmt; int ret, flags = O_RDONLY; char errbuf[128]; ret = av_parse_video_rate(&fbdev->framerate_q, fbdev->framerate); if (ret < 0) { av_log(avctx, AV_LOG_ERROR, "Could not parse framerate '%s'.\n", fbdev->framerate); return ret; } if (!(st = avformat_new_stream(avctx, NULL))) return AVERROR(ENOMEM); avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in microseconds */ /* NONBLOCK is ignored by the fbdev driver, only set for consistency */ if (avctx->flags & AVFMT_FLAG_NONBLOCK) flags |= O_NONBLOCK; if ((fbdev->fd = avpriv_open(avctx->filename, flags)) == -1) { ret = AVERROR(errno); av_strerror(ret, errbuf, sizeof(errbuf)); av_log(avctx, AV_LOG_ERROR, "Could not open framebuffer device '%s': %s\n", avctx->filename, errbuf); return ret; } if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) { ret = AVERROR(errno); av_strerror(ret, errbuf, sizeof(errbuf)); av_log(avctx, AV_LOG_ERROR, "FBIOGET_VSCREENINFO: %s\n", errbuf); goto fail; } if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) { ret = AVERROR(errno); av_strerror(ret, errbuf, sizeof(errbuf)); av_log(avctx, AV_LOG_ERROR, "FBIOGET_FSCREENINFO: %s\n", errbuf); goto fail; } pix_fmt = get_pixfmt_from_fb_varinfo(&fbdev->varinfo); if (pix_fmt == AV_PIX_FMT_NONE) { ret = AVERROR(EINVAL); av_log(avctx, AV_LOG_ERROR, "Framebuffer pixel format not supported.\n"); goto fail; } fbdev->width = fbdev->varinfo.xres; fbdev->height = fbdev->varinfo.yres; fbdev->bytes_per_pixel = (fbdev->varinfo.bits_per_pixel + 7) >> 3; fbdev->frame_linesize = fbdev->width * fbdev->bytes_per_pixel; fbdev->frame_size = fbdev->frame_linesize * fbdev->height; fbdev->time_frame = AV_NOPTS_VALUE; fbdev->data = mmap(NULL, fbdev->fixinfo.smem_len, PROT_READ, MAP_SHARED, fbdev->fd, 0); if (fbdev->data == MAP_FAILED) { ret = AVERROR(errno); av_strerror(ret, errbuf, sizeof(errbuf)); av_log(avctx, AV_LOG_ERROR, "Error in mmap(): %s\n", errbuf); goto fail; } st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO; st->codecpar->codec_id = AV_CODEC_ID_RAWVIDEO; st->codecpar->width = fbdev->width; st->codecpar->height = fbdev->height; st->codecpar->format = pix_fmt; st->codecpar->bit_rate = fbdev->width * fbdev->height * fbdev->bytes_per_pixel * av_q2d(fbdev->framerate_q) * 8; st->avg_frame_rate = fbdev->framerate_q; av_log(avctx, AV_LOG_INFO, "w:%d h:%d bpp:%d pixfmt:%s fps:%d/%d bit_rate:%d\n", fbdev->width, fbdev->height, fbdev->varinfo.bits_per_pixel, av_get_pix_fmt_name(pix_fmt), fbdev->framerate_q.num, fbdev->framerate_q.den, st->codecpar->bit_rate); return 0; fail: close(fbdev->fd); return ret; } static int fbdev_read_packet(AVFormatContext *avctx, AVPacket *pkt) { FBDevContext *fbdev = avctx->priv_data; int64_t curtime, delay; struct timespec ts; int i, ret; uint8_t *pin, *pout; if (fbdev->time_frame == AV_NOPTS_VALUE) fbdev->time_frame = av_gettime(); /* wait based on the frame rate */ curtime = av_gettime(); delay = fbdev->time_frame - curtime; av_log(avctx, AV_LOG_TRACE, "time_frame:%"PRId64" curtime:%"PRId64" delay:%"PRId64"\n", fbdev->time_frame, curtime, delay); if (delay > 0) { if (avctx->flags & AVFMT_FLAG_NONBLOCK) return AVERROR(EAGAIN); ts.tv_sec = delay / 1000000; ts.tv_nsec = (delay % 1000000) * 1000; while (nanosleep(&ts, &ts) < 0 && errno == EINTR); } /* compute the time of the next frame */ fbdev->time_frame += INT64_C(1000000) / av_q2d(fbdev->framerate_q); if ((ret = av_new_packet(pkt, fbdev->frame_size)) < 0) return ret; /* refresh fbdev->varinfo, visible data position may change at each call */ if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) { char errbuf[128]; av_strerror(AVERROR(errno), errbuf, sizeof(errbuf)); av_log(avctx, AV_LOG_WARNING, "Error refreshing variable info: %s\n", errbuf); } pkt->pts = curtime; /* compute visible data offset */ pin = fbdev->data + fbdev->bytes_per_pixel * fbdev->varinfo.xoffset + fbdev->varinfo.yoffset * fbdev->fixinfo.line_length; pout = pkt->data; // TODO it'd be nice if the lines were aligned for (i = 0; i < fbdev->height; i++) { memcpy(pout, pin, fbdev->frame_linesize); pin += fbdev->fixinfo.line_length; pout += fbdev->frame_linesize; } return fbdev->frame_size; } static av_cold int fbdev_read_close(AVFormatContext *avctx) { FBDevContext *fbdev = avctx->priv_data; munmap(fbdev->data, fbdev->frame_size); close(fbdev->fd); return 0; } #define OFFSET(x) offsetof(FBDevContext, x) #define DEC AV_OPT_FLAG_DECODING_PARAM static const AVOption options[] = { { "framerate","", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = "25"}, 0, 0, DEC }, { NULL }, }; static const AVClass fbdev_class = { .class_name = "fbdev indev", .item_name = av_default_item_name, .option = options, .version = LIBAVUTIL_VERSION_INT, }; AVInputFormat ff_fbdev_demuxer = { .name = "fbdev", .long_name = NULL_IF_CONFIG_SMALL("Linux framebuffer"), .priv_data_size = sizeof(FBDevContext), .read_header = fbdev_read_header, .read_packet = fbdev_read_packet, .read_close = fbdev_read_close, .flags = AVFMT_NOFILE, .priv_class = &fbdev_class, };