[PATCH] Add Linux framebuffer 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 | 15 +++
libavdevice/Makefile | 1 +
libavdevice/alldevices.c | 1 +
libavdevice/framebuffer.c | 216 +++++++++++++++++++++++++++++++++++++++++++++
6 files changed, 236 insertions(+), 0 deletions(-)
create mode 100644 libavdevice/framebuffer.c
diff --git a/Changelog b/Changelog
index 8b7efb6..1c9166e 100644
--- a/Changelog
+++ b/Changelog
@@ -74,6 +74,7 @@ version <next>:
- Lagarith decoder
- ffmpeg -copytb option added
- IVF muxer added
+- Linux framebuffer input device added
version 0.6:
diff --git a/configure b/configure
index 001f00a..e75ad41 100755
--- a/configure
+++ b/configure
@@ -1387,6 +1387,7 @@ 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"
+framebuffer_indev_deps="linux_fb_h"
jack_indev_deps="jack_jack_h"
libdc1394_indev_deps="libdc1394"
oss_indev_deps_any="soundcard_h sys_soundcard_h"
@@ -2848,6 +2849,7 @@ if enabled network; then
fi
fi
+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..f2fb30e 100644
--- a/doc/indevs.texi
+++ b/doc/indevs.texi
@@ -59,6 +59,21 @@ BSD video input device.
Linux DV 1394 input device.
+ at section framebuffer
+
+Linux framebuffer input device.
+
+For example, to record from the framebuffer device /dev/fb0 with
+ at file{ffmpeg}:
+ at example
+ffmpeg -f framebuffer -r 10 -i /dev/fb0 out.avi
+ at end example
+
+You can take a single screenshot image with the command:
+ at example
+ffmpeg -f framebuffer -vframes -r 1 -i /dev/fb0 screenshot.jpeg
+ at end example
+
@section jack
JACK input device.
diff --git a/libavdevice/Makefile b/libavdevice/Makefile
index 1c0630b..f5afeb2 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_FRAMEBUFFER_INDEV) += framebuffer.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 de3bc82..4e79467 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 (FRAMEBUFFER, framebuffer);
REGISTER_INDEV (JACK, jack);
REGISTER_INOUTDEV (OSS, oss);
REGISTER_INDEV (V4L2, v4l2);
diff --git a/libavdevice/framebuffer.c b/libavdevice/framebuffer.c
new file mode 100644
index 0000000..8acfa7c
--- /dev/null
+++ b/libavdevice/framebuffer.c
@@ -0,0 +1,216 @@
+/*
+ * Copyright (c) 2010 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,
+ * based on code from fbgrab.c by Gunnar Monell.
+ */
+
+#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"
+
+typedef struct {
+ int frame_size; ///< size in bytes of a grabbed frame
+ AVRational time_base; ///< time base
+ int64_t time_frame; ///< current time
+
+ int frame_linesize; ///< linesize of the output frame
+ int linesize; ///< linesize of the read framebuffer
+ int height; ///< height of the grab frame
+ int width; ///< width of the grab frame
+ int fd; ///< framebuffer device file descriptor
+
+ uint8_t *data; ///< image data
+} FrameBufferContext;
+
+/**
+ * Initialize the fb grab device demuxer (public device demuxer API).
+ */
+av_cold static int frame_buffer_read_header(AVFormatContext *avctx, AVFormatParameters *ap)
+{
+ FrameBufferContext *fb = avctx->priv_data;
+ struct fb_var_screeninfo fb_varinfo;
+ struct fb_fix_screeninfo fb_fixinfo;
+ AVStream *st = NULL;
+ enum PixelFormat pix_fmt;
+ int ret, bits_per_pixel, flags = O_RDONLY;
+
+ if (!(st = av_new_stream(avctx, 0)))
+ return AVERROR(ENOMEM);
+
+ if (avctx->flags & AVFMT_FLAG_NONBLOCK)
+ flags |= O_NONBLOCK;
+
+ if ((fb->fd = open(avctx->filename, flags)) == -1) {
+ ret = AVERROR(errno);
+ av_log(avctx, AV_LOG_ERROR, "Could not open framebuffer device '%s'.\n", avctx->filename);
+ goto fail;
+ }
+
+ if (ioctl(fb->fd, FBIOGET_VSCREENINFO, &fb_varinfo) < 0) {
+ ret = AVERROR(errno);
+ av_log(avctx, AV_LOG_ERROR, "FBIOGET_VSCREENINFO: %s\n", strerror(errno));
+ goto fail;
+ }
+
+ if (ioctl(fb->fd, FBIOGET_FSCREENINFO, &fb_fixinfo) < 0) {
+ ret = AVERROR(errno);
+ av_log(avctx, AV_LOG_ERROR, "FBIOGET_FSCREENINFO: %s\n", strerror(errno));
+ goto fail;
+ }
+
+ if (ap->time_base.den <= 0) {
+ ret = AVERROR(EINVAL);
+ av_log(avctx, AV_LOG_ERROR, "Invalid time base %d/%d\n", ap->time_base.num, ap->time_base.den);
+ goto fail;
+ }
+
+ av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in microseconds */
+
+ fb->width = fb_varinfo.xres;
+ fb->height = fb_varinfo.yres;
+ bits_per_pixel = fb_varinfo.bits_per_pixel;
+
+ switch (bits_per_pixel) {
+ case 8: pix_fmt = PIX_FMT_PAL8 ; break;
+ case 15: pix_fmt = PIX_FMT_BGR555; break;
+ case 16: pix_fmt = PIX_FMT_RGB565; break;
+ case 24: pix_fmt = PIX_FMT_RGB24 ; break;
+ case 32: pix_fmt = PIX_FMT_RGB32 ; break;
+ default:
+ ret = AVERROR(EINVAL);
+ av_log(avctx, AV_LOG_ERROR, "Image with bits per pixel depth %d not supported.\n",
+ bits_per_pixel);
+ goto fail;
+ }
+
+ fb->frame_linesize = fb_varinfo.xres * ((bits_per_pixel + 7)>>3);
+ fb->frame_size = fb->frame_linesize * fb_varinfo.yres;
+ fb->linesize = fb_fixinfo.line_length;
+ fb->time_base = ap->time_base;
+ fb->time_frame = av_gettime() / av_q2d(ap->time_base);
+ fb->data = mmap(NULL, fb_fixinfo.line_length * fb_varinfo.yres,
+ PROT_READ, MAP_SHARED, fb->fd, 0);
+ if ((int)fb->data == -1) {
+ 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 = fb->width;
+ st->codec->height = fb->height;
+ st->codec->pix_fmt = pix_fmt;
+ st->codec->time_base = ap->time_base;
+ st->codec->bit_rate = fb->frame_size / 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",
+ fb->width, fb->height, 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:
+ if (fb->fd >= 0)
+ close(fb->fd);
+ return ret;
+}
+
+/**
+ * Grab a frame from the frame buffer device.
+ *
+ * @param pkt packet holding the grabbed frame
+ * @return frame size in bytes
+ */
+static int frame_buffer_read_packet(AVFormatContext *avctx, AVPacket *pkt)
+{
+ FrameBufferContext *fb = avctx->priv_data;
+ int64_t curtime, delay;
+ struct timespec ts;
+ int i, ret;
+ uint8_t *pin, *pout;
+
+ /* wait based on the frame rate */
+ while (1) {
+ curtime = av_gettime();
+ delay = curtime - fb->time_frame * av_q2d(fb->time_base);
+ if (delay >= 0) {
+ fb->time_frame += INT64_C(1000000) * av_q2d(fb->time_base);
+ break;
+ }
+ if (avctx->flags & AVFMT_FLAG_NONBLOCK)
+ return AVERROR(EAGAIN);
+ ts.tv_sec = delay / 1000000;
+ ts.tv_nsec = (delay % 1000000) * 1000;
+ nanosleep(&ts, NULL);
+ }
+
+ if ((ret = av_new_packet(pkt, fb->frame_size)) < 0)
+ return ret;
+
+ pkt->pts = curtime;
+ pin = fb->data;
+ pout = pkt->data;
+ for (i = 0; i < fb->height; i++) {
+ memcpy(pout, pin, fb->frame_linesize);
+ pin += fb->linesize;
+ pout += fb->frame_linesize;
+ }
+
+ return fb->frame_size;
+}
+
+/**
+ * Close framebuffer input device.
+ *
+ * @return a negative value in case of errors, 0 otherwise
+ */
+av_cold static int frame_buffer_read_close(AVFormatContext *avctx)
+{
+ FrameBufferContext *fb = avctx->priv_data;
+
+ munmap(fb->data, fb->frame_size);
+ close(fb->fd);
+
+ return 0;
+}
+
+AVInputFormat framebuffer_demuxer = {
+ .name = "framebuffer",
+ .long_name = NULL_IF_CONFIG_SMALL("Linux framebuffer"),
+ .priv_data_size = sizeof(FrameBufferContext),
+ .read_header = frame_buffer_read_header,
+ .read_packet = frame_buffer_read_packet,
+ .read_close = frame_buffer_read_close,
+ .flags = AVFMT_NOFILE,
+};
--
1.7.2.3
--7iMSBzlTiPOCCT2k--
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