fbdev_enc.c 7.43 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
/*
 * Copyright (c) 2013 Lukasz Marek
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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.
 *
 * FFmpeg 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 FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <linux/fb.h>
#include "libavutil/pixdesc.h"
#include "libavutil/log.h"
#include "libavutil/mem.h"
#include "libavutil/opt.h"
#include "libavformat/avformat.h"
31
#include "fbdev_common.h"
32
#include "avdevice.h"
33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48

typedef struct {
    AVClass *class;                   ///< class for private options
    int xoffset;                      ///< x coordinate of top left corner
    int yoffset;                      ///< y coordinate of top left corner
    struct fb_var_screeninfo varinfo; ///< framebuffer variable info
    struct fb_fix_screeninfo fixinfo; ///< framebuffer fixed info
    int fd;                           ///< framebuffer device file descriptor
    uint8_t *data;                    ///< framebuffer data
} FBDevContext;

static av_cold int fbdev_write_header(AVFormatContext *h)
{
    FBDevContext *fbdev = h->priv_data;
    enum AVPixelFormat pix_fmt;
    int ret, flags = O_RDWR;
49
    const char* device;
50

51 52
    if (h->nb_streams != 1 || h->streams[0]->codec->codec_type != AVMEDIA_TYPE_VIDEO) {
        av_log(fbdev, AV_LOG_ERROR, "Only a single video stream is supported.\n");
53 54 55
        return AVERROR(EINVAL);
    }

56 57 58 59 60 61
    if (h->filename[0])
        device = h->filename;
    else
        device = ff_fbdev_default_device();

    if ((fbdev->fd = avpriv_open(device, flags)) == -1) {
62 63 64
        ret = AVERROR(errno);
        av_log(h, AV_LOG_ERROR,
               "Could not open framebuffer device '%s': %s\n",
65
               device, av_err2str(ret));
66 67 68 69 70 71 72 73 74 75 76 77 78 79 80
        return ret;
    }

    if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
        ret = AVERROR(errno);
        av_log(h, AV_LOG_ERROR, "FBIOGET_VSCREENINFO: %s\n", av_err2str(ret));
        goto fail;
    }

    if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) {
        ret = AVERROR(errno);
        av_log(h, AV_LOG_ERROR, "FBIOGET_FSCREENINFO: %s\n", av_err2str(ret));
        goto fail;
    }

81
    pix_fmt = ff_get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107
    if (pix_fmt == AV_PIX_FMT_NONE) {
        ret = AVERROR(EINVAL);
        av_log(h, AV_LOG_ERROR, "Framebuffer pixel format not supported.\n");
        goto fail;
    }

    fbdev->data = mmap(NULL, fbdev->fixinfo.smem_len, PROT_WRITE, MAP_SHARED, fbdev->fd, 0);
    if (fbdev->data == MAP_FAILED) {
        ret = AVERROR(errno);
        av_log(h, AV_LOG_ERROR, "Error in mmap(): %s\n", av_err2str(ret));
        goto fail;
    }

    return 0;
  fail:
    close(fbdev->fd);
    return ret;
}

static int fbdev_write_packet(AVFormatContext *h, AVPacket *pkt)
{
    FBDevContext *fbdev = h->priv_data;
    uint8_t *pin, *pout;
    enum AVPixelFormat fb_pix_fmt;
    int disp_height;
    int bytes_to_copy;
108
    AVCodecContext *codec_ctx = h->streams[0]->codec;
109 110 111 112 113
    enum AVPixelFormat video_pix_fmt = codec_ctx->pix_fmt;
    int video_width = codec_ctx->width;
    int video_height = codec_ctx->height;
    int bytes_per_pixel = ((codec_ctx->bits_per_coded_sample + 7) >> 3);
    int src_line_size = video_width * bytes_per_pixel;
114
    int i;
115 116 117 118 119

    if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0)
        av_log(h, AV_LOG_WARNING,
               "Error refreshing variable info: %s\n", av_err2str(AVERROR(errno)));

120
    fb_pix_fmt = ff_get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169

    if (fb_pix_fmt != video_pix_fmt) {
        av_log(h, AV_LOG_ERROR, "Pixel format %s is not supported, use %s\n",
               av_get_pix_fmt_name(video_pix_fmt), av_get_pix_fmt_name(fb_pix_fmt));
        return AVERROR(EINVAL);
    }

    disp_height = FFMIN(fbdev->varinfo.yres, video_height);
    bytes_to_copy = FFMIN(fbdev->varinfo.xres, video_width) * bytes_per_pixel;

    pin  = pkt->data;
    pout = fbdev->data +
           bytes_per_pixel * fbdev->varinfo.xoffset +
           fbdev->varinfo.yoffset * fbdev->fixinfo.line_length;

    if (fbdev->xoffset) {
        if (fbdev->xoffset < 0) {
            if (-fbdev->xoffset >= video_width) //nothing to display
                return 0;
            bytes_to_copy += fbdev->xoffset * bytes_per_pixel;
            pin -= fbdev->xoffset * bytes_per_pixel;
        } else {
            int diff = (video_width + fbdev->xoffset) - fbdev->varinfo.xres;
            if (diff > 0) {
                if (diff >= video_width) //nothing to display
                    return 0;
                bytes_to_copy -= diff * bytes_per_pixel;
            }
            pout += bytes_per_pixel * fbdev->xoffset;
        }
    }

    if (fbdev->yoffset) {
        if (fbdev->yoffset < 0) {
            if (-fbdev->yoffset >= video_height) //nothing to display
                return 0;
            disp_height += fbdev->yoffset;
            pin -= fbdev->yoffset * src_line_size;
        } else {
            int diff = (video_height + fbdev->yoffset) - fbdev->varinfo.yres;
            if (diff > 0) {
                if (diff >= video_height) //nothing to display
                    return 0;
                disp_height -= diff;
            }
            pout += fbdev->yoffset * fbdev->fixinfo.line_length;
        }
    }

170
    for (i = 0; i < disp_height; i++) {
171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186
        memcpy(pout, pin, bytes_to_copy);
        pout += fbdev->fixinfo.line_length;
        pin  += src_line_size;
    }

    return 0;
}

static av_cold int fbdev_write_trailer(AVFormatContext *h)
{
    FBDevContext *fbdev = h->priv_data;
    munmap(fbdev->data, fbdev->fixinfo.smem_len);
    close(fbdev->fd);
    return 0;
}

187 188
static int fbdev_get_device_list(AVFormatContext *s, AVDeviceInfoList *device_list)
{
189
    return ff_fbdev_get_device_list(device_list);
190 191
}

192 193 194 195 196 197 198 199 200 201 202 203 204
#define OFFSET(x) offsetof(FBDevContext, x)
#define ENC AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
    { "xoffset", "set x coordinate of top left corner", OFFSET(xoffset), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, ENC },
    { "yoffset", "set y coordinate of top left corner", OFFSET(yoffset), AV_OPT_TYPE_INT, {.i64 = 0}, INT_MIN, INT_MAX, ENC },
    { NULL }
};

static const AVClass fbdev_class = {
    .class_name = "fbdev outdev",
    .item_name  = av_default_item_name,
    .option     = options,
    .version    = LIBAVUTIL_VERSION_INT,
205
    .category   = AV_CLASS_CATEGORY_DEVICE_VIDEO_OUTPUT,
206 207 208 209 210 211 212 213 214 215 216
};

AVOutputFormat ff_fbdev_muxer = {
    .name           = "fbdev",
    .long_name      = NULL_IF_CONFIG_SMALL("Linux framebuffer"),
    .priv_data_size = sizeof(FBDevContext),
    .audio_codec    = AV_CODEC_ID_NONE,
    .video_codec    = AV_CODEC_ID_RAWVIDEO,
    .write_header   = fbdev_write_header,
    .write_packet   = fbdev_write_packet,
    .write_trailer  = fbdev_write_trailer,
217
    .get_device_list = fbdev_get_device_list,
218 219 220
    .flags          = AVFMT_NOFILE | AVFMT_VARIABLE_FPS | AVFMT_NOTIMESTAMPS,
    .priv_class     = &fbdev_class,
};