[PATCH] lavdev: add Linux framebuffer input device
Stefano Sabatini
stefano.sabatini-lala
Tue Jan 25 19:40:29 CET 2011
Based on a patch by Giliard B. de Freitas /com/gmail/giliarde.
See thread:
Subject: [FFmpeg-devel] Fwd: framebuffer device demuxer
Date: Sat, 23 May 2009 09:32:13 -0300
---
Changelog | 1 +
configure | 2 +
doc/indevs.texi | 25 +++++
libavdevice/Makefile | 1 +
libavdevice/alldevices.c | 1 +
libavdevice/avdevice.h | 4 +-
libavdevice/fbdev.c | 252 ++++++++++++++++++++++++++++++++++++++++++++++
7 files changed, 284 insertions(+), 2 deletions(-)
create mode 100644 libavdevice/fbdev.c
diff --git a/Changelog b/Changelog
index dc47dab..e14a426 100644
--- a/Changelog
+++ b/Changelog
@@ -77,6 +77,7 @@ version <next>:
- Wing Commander IV movies decoder added
- movie source added
- Bink version 'b' audio and video decoder
+- Linux framebuffer input device added
version 0.6:
diff --git a/configure b/configure
index 04f6e13..749dde5 100755
--- a/configure
+++ b/configure
@@ -1401,6 +1401,7 @@ alsa_indev_deps="alsa_asoundlib_h snd_pcm_htimestamp"
alsa_outdev_deps="alsa_asoundlib_h"
bktr_indev_deps_any="dev_bktr_ioctl_bt848_h machine_ioctl_bt848_h dev_video_bktr_ioctl_bt848_h dev_ic_bt8xx_h"
dv1394_indev_deps="dv1394 dv_demuxer"
+fbdev_indev_deps="linux_fb_h"
jack_indev_deps="jack_jack_h"
libdc1394_indev_deps="libdc1394"
oss_indev_deps_any="soundcard_h sys_soundcard_h"
@@ -2870,6 +2871,7 @@ fi
texi2html -version > /dev/null 2>&1 && enable texi2html || disable texi2html
+check_header linux/fb.h
check_header linux/videodev.h
check_header linux/videodev2.h
check_header sys/videoio.h
diff --git a/doc/indevs.texi b/doc/indevs.texi
index 8e862ff..1cd2dd6 100644
--- a/doc/indevs.texi
+++ b/doc/indevs.texi
@@ -59,6 +59,31 @@ BSD video input device.
Linux DV 1394 input device.
+ at section fbdev
+
+Linux framebuffer input device.
+
+The Linux framebuffer is a graphic hardware-independent abstraction
+layer to show graphics on a computer monitor, typically on the
+console. It is accessed through a file device node, usually
+ at file{/dev/fb0}.
+
+For more detailed information read the file
+Documentation/fb/framebuffer.txt included in the Linux source tree.
+
+For example, to record from the framebuffer device @file{/dev/fb0} with
+ at file{ffmpeg}:
+ at example
+ffmpeg -f fbdev -r 10 -i /dev/fb0 out.avi
+ at end example
+
+You can take a single screenshot image with the command:
+ at example
+ffmpeg -f fbdev -vframes 1 -r 1 -i /dev/fb0 screenshot.jpeg
+ at end example
+
+See also @url{http://linux-fbdev.sourceforge.net/}, and fbset(1).
+
@section jack
JACK input device.
diff --git a/libavdevice/Makefile b/libavdevice/Makefile
index be28f4a..472cb95 100644
--- a/libavdevice/Makefile
+++ b/libavdevice/Makefile
@@ -14,6 +14,7 @@ OBJS-$(CONFIG_ALSA_OUTDEV) += alsa-audio-common.o \
alsa-audio-enc.o
OBJS-$(CONFIG_BKTR_INDEV) += bktr.o
OBJS-$(CONFIG_DV1394_INDEV) += dv1394.o
+OBJS-$(CONFIG_FBDEV_INDEV) += fbdev.o
OBJS-$(CONFIG_JACK_INDEV) += jack_audio.o
OBJS-$(CONFIG_OSS_INDEV) += oss_audio.o
OBJS-$(CONFIG_OSS_OUTDEV) += oss_audio.o
diff --git a/libavdevice/alldevices.c b/libavdevice/alldevices.c
index ce06bf2..0c000dc 100644
--- a/libavdevice/alldevices.c
+++ b/libavdevice/alldevices.c
@@ -42,6 +42,7 @@ void avdevice_register_all(void)
REGISTER_INOUTDEV (ALSA, alsa);
REGISTER_INDEV (BKTR, bktr);
REGISTER_INDEV (DV1394, dv1394);
+ REGISTER_INDEV (FBDEV, fbdev);
REGISTER_INDEV (JACK, jack);
REGISTER_INOUTDEV (OSS, oss);
REGISTER_INDEV (V4L2, v4l2);
diff --git a/libavdevice/avdevice.h b/libavdevice/avdevice.h
index 5c3739f..23e3f31 100644
--- a/libavdevice/avdevice.h
+++ b/libavdevice/avdevice.h
@@ -22,8 +22,8 @@
#include "libavutil/avutil.h"
#define LIBAVDEVICE_VERSION_MAJOR 52
-#define LIBAVDEVICE_VERSION_MINOR 2
-#define LIBAVDEVICE_VERSION_MICRO 3
+#define LIBAVDEVICE_VERSION_MINOR 3
+#define LIBAVDEVICE_VERSION_MICRO 0
#define LIBAVDEVICE_VERSION_INT AV_VERSION_INT(LIBAVDEVICE_VERSION_MAJOR, \
LIBAVDEVICE_VERSION_MINOR, \
diff --git a/libavdevice/fbdev.c b/libavdevice/fbdev.c
new file mode 100644
index 0000000..0c282f4
--- /dev/null
+++ b/libavdevice/fbdev.c
@@ -0,0 +1,252 @@
+/*
+ * Copyright (c) 2011 Stefano Sabatini
+ * Copyright (c) 2009 Giliard B. de Freitas <giliarde at gmail.com>
+ * Copyright (C) 2002 Gunnar Monell <gmo at linux.nu>
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * Linux framebuffer input device,
+ * inspired by code from fbgrab.c by Gunnar Monell.
+ * See also http://linux-fbdev.sourceforge.net/.
+ */
+
+/* #define DEBUG */
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <sys/time.h>
+#include <sys/mman.h>
+#include <time.h>
+#include <linux/fb.h>
+
+#include "libavutil/mem.h"
+#include "libavutil/pixdesc.h"
+#include "libavformat/avformat.h"
+
+struct rgb_pixfmt_map_entry {
+ int bits_per_pixel;
+ int red_offset, green_offset, blue_offset, alpha_offset;
+ enum PixelFormat 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, PIX_FMT_RGBA },
+ { 32, 16, 8, 0, 24, PIX_FMT_BGRA },
+ { 32, 8, 16, 24, 0, PIX_FMT_ARGB },
+ { 32, 3, 2, 8, 0, PIX_FMT_ABGR },
+ { 24, 0, 8, 16, 0, PIX_FMT_RGB24 },
+ { 24, 16, 8, 0, 0, PIX_FMT_BGR24 },
+};
+
+static enum PixelFormat
+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 PIX_FMT_NONE;
+}
+
+typedef struct {
+ int frame_size; ///< size in bytes of a grabbed frame
+ AVRational time_base; ///< time base
+ int64_t time_frame; ///< time for the next frame to output (in 1/1000000 units)
+
+ int fd; ///< framebuffer device file descriptor
+ int width, heigth; ///< 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;
+
+av_cold static int fbdev_read_header(AVFormatContext *avctx,
+ AVFormatParameters *ap)
+{
+ FBDevContext *fbdev = avctx->priv_data;
+ AVStream *st = NULL;
+ enum PixelFormat pix_fmt;
+ int ret, flags = O_RDONLY;
+
+ if (!(st = av_new_stream(avctx, 0)))
+ return AVERROR(ENOMEM);
+ av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in microseconds */
+
+ if (ap->time_base.den <= 0) {
+ av_log(avctx, AV_LOG_ERROR, "Invalid time base %d/%d\n",
+ ap->time_base.num, ap->time_base.den);
+ return AVERROR(EINVAL);
+ }
+
+ /* NONBLOCK is ignored by the fbdev driver, only set for consistency */
+ if (avctx->flags & AVFMT_FLAG_NONBLOCK)
+ flags |= O_NONBLOCK;
+
+ if ((fbdev->fd = open(avctx->filename, flags)) == -1) {
+ ret = AVERROR(errno);
+ av_log(avctx, AV_LOG_ERROR,
+ "Could not open framebuffer device '%s': %s\n",
+ avctx->filename, strerror(ret));
+ return ret;
+ }
+
+ if (ioctl(fbdev->fd, FBIOGET_VSCREENINFO, &fbdev->varinfo) < 0) {
+ ret = AVERROR(errno);
+ av_log(avctx, AV_LOG_ERROR,
+ "FBIOGET_VSCREENINFO: %s\n", strerror(errno));
+ goto fail;
+ }
+
+ if (ioctl(fbdev->fd, FBIOGET_FSCREENINFO, &fbdev->fixinfo) < 0) {
+ ret = AVERROR(errno);
+ av_log(avctx, AV_LOG_ERROR,
+ "FBIOGET_FSCREENINFO: %s\n", strerror(errno));
+ goto fail;
+ }
+
+ pix_fmt = get_pixfmt_from_fb_varinfo(&fbdev->varinfo);
+ if (pix_fmt == 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->heigth = 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->heigth;
+ fbdev->time_base = ap->time_base;
+ 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_log(avctx, AV_LOG_ERROR, "Error in mmap(): %s\n", strerror(errno));
+ goto fail;
+ }
+
+ st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
+ st->codec->codec_id = CODEC_ID_RAWVIDEO;
+ st->codec->width = fbdev->width;
+ st->codec->height = fbdev->heigth;
+ st->codec->pix_fmt = pix_fmt;
+ st->codec->time_base = ap->time_base;
+ st->codec->bit_rate =
+ fbdev->width * fbdev->heigth * fbdev->bytes_per_pixel / av_q2d(ap->time_base) * 8;
+
+ av_log(avctx, AV_LOG_INFO,
+ "w:%d h:%d bpp:%d pixfmt:%s tb:%d/%d bit_rate:%d\n",
+ fbdev->width, fbdev->heigth, fbdev->varinfo.bits_per_pixel,
+ av_pix_fmt_descriptors[pix_fmt].name,
+ ap->time_base.num, ap->time_base.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 */
+ while (1) {
+ curtime = av_gettime();
+ delay = fbdev->time_frame - curtime;
+ av_dlog(avctx,
+ "time_frame:%"PRId64" curtime:%"PRId64" delay:%"PRId64"\n",
+ fbdev->time_frame, curtime, delay);
+ if (delay <= 0) {
+ fbdev->time_frame += INT64_C(1000000) * av_q2d(fbdev->time_base);
+ break;
+ }
+ if (avctx->flags & AVFMT_FLAG_NONBLOCK)
+ return AVERROR(EAGAIN);
+ ts.tv_sec = delay / 1000000;
+ ts.tv_nsec = (delay % 1000000) * 1000;
+ while (nanosleep(&ts, &ts) == EINTR);
+ }
+
+ 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)
+ av_log(avctx, AV_LOG_WARNING,
+ "Error refreshing variable info: %s\n", strerror(errno));
+
+ 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;
+
+ for (i = 0; i < fbdev->heigth; i++) {
+ memcpy(pout, pin, fbdev->frame_linesize);
+ pin += fbdev->fixinfo.line_length;
+ pout += fbdev->frame_linesize;
+ }
+
+ return fbdev->frame_size;
+}
+
+av_cold static int fbdev_read_close(AVFormatContext *avctx)
+{
+ FBDevContext *fbdev = avctx->priv_data;
+
+ munmap(fbdev->data, fbdev->frame_size);
+ close(fbdev->fd);
+
+ return 0;
+}
+
+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,
+};
--
1.7.2.3
--GvXjxJ+pjyke8COw--
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