/* * Copyright (c) 2011 Stefano Sabatini * Copyright (c) 2009 Giliard B. de Freitas <giliarde@gmail.com> * Copyright (C) 2002 Gunnar Monell <gmo@linux.nu> * * 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 <unistd.h>#include <fcntl.h>#include <sys/ioctl.h>#include <sys/mman.h>#include <time.h>#include <linux/fb.h> #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->codec->codec_type = AVMEDIA_TYPE_VIDEO;    st->codec->codec_id   = AV_CODEC_ID_RAWVIDEO;    st->codec->width      = fbdev->width;    st->codec->height     = fbdev->height;    st->codec->pix_fmt    = pix_fmt;    st->codec->time_base  = (AVRational){fbdev->framerate_q.den, fbdev->framerate_q.num};    st->codec->bit_rate   =        fbdev->width * fbdev->height * fbdev->bytes_per_pixel * av_q2d(fbdev->framerate_q) * 8;     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->codec->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_PARAMstatic 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,};