[FFmpeg-devel] [PATCH 2/2] lavd: add v4l2 outdev.

Clément Bœsch ubitux at gmail.com
Sun May 19 23:39:47 CEST 2013


TODO: lavd minor bump
---
 Changelog                |   1 +
 configure                |   1 +
 libavdevice/Makefile     |   1 +
 libavdevice/alldevices.c |   2 +-
 libavdevice/v4l2enc.c    | 108 +++++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 112 insertions(+), 1 deletion(-)
 create mode 100644 libavdevice/v4l2enc.c

diff --git a/Changelog b/Changelog
index 249e8c3..2ed6c87 100644
--- a/Changelog
+++ b/Changelog
@@ -51,6 +51,7 @@ version <next>:
 - Apple Intermediate Codec decoder
 - Escape 130 video decoder
 - FTP protocol support
+- V4L2 output device
 
 
 version 1.2:
diff --git a/configure b/configure
index 6fe7945..01f14fe 100755
--- a/configure
+++ b/configure
@@ -2079,6 +2079,7 @@ sndio_indev_deps="sndio_h"
 sndio_outdev_deps="sndio_h"
 v4l_indev_deps="linux_videodev_h"
 v4l2_indev_deps_any="linux_videodev2_h sys_videoio_h"
+v4l2_outdev_deps_any="linux_videodev2_h sys_videoio_h"
 vfwcap_indev_deps="capCreateCaptureWindow vfwcap_defines"
 vfwcap_indev_extralibs="-lavicap32"
 x11grab_indev_deps="x11grab"
diff --git a/libavdevice/Makefile b/libavdevice/Makefile
index dfde768..f19ccdb 100644
--- a/libavdevice/Makefile
+++ b/libavdevice/Makefile
@@ -33,6 +33,7 @@ OBJS-$(CONFIG_SDL_OUTDEV)                += sdl.o
 OBJS-$(CONFIG_SNDIO_INDEV)               += sndio_common.o sndio_dec.o
 OBJS-$(CONFIG_SNDIO_OUTDEV)              += sndio_common.o sndio_enc.o
 OBJS-$(CONFIG_V4L2_INDEV)                += v4l2.o v4l2-common.o timefilter.o
+OBJS-$(CONFIG_V4L2_OUTDEV)               += v4l2enc.o v4l2-common.o
 OBJS-$(CONFIG_V4L_INDEV)                 += v4l.o
 OBJS-$(CONFIG_VFWCAP_INDEV)              += vfwcap.o
 OBJS-$(CONFIG_X11GRAB_INDEV)             += x11grab.o
diff --git a/libavdevice/alldevices.c b/libavdevice/alldevices.c
index daa6638..9672a47 100644
--- a/libavdevice/alldevices.c
+++ b/libavdevice/alldevices.c
@@ -60,7 +60,7 @@ void avdevice_register_all(void)
     REGISTER_INDEV   (PULSE,            pulse);
     REGISTER_OUTDEV  (SDL,              sdl);
     REGISTER_INOUTDEV(SNDIO,            sndio);
-    REGISTER_INDEV   (V4L2,             v4l2);
+    REGISTER_INOUTDEV(V4L2,             v4l2);
 //    REGISTER_INDEV   (V4L,              v4l
     REGISTER_INDEV   (VFWCAP,           vfwcap);
     REGISTER_INDEV   (X11GRAB,          x11grab);
diff --git a/libavdevice/v4l2enc.c b/libavdevice/v4l2enc.c
new file mode 100644
index 0000000..eaa77ea
--- /dev/null
+++ b/libavdevice/v4l2enc.c
@@ -0,0 +1,108 @@
+/*
+ * Copyright (c) 2013 Clément Bœsch
+ *
+ * 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 "v4l2-common.h"
+#include "avdevice.h"
+
+struct video_data {
+    int fd;
+};
+
+static av_cold int write_header(AVFormatContext *s1)
+{
+    int res = 0, flags = O_RDWR;
+    struct v4l2_format fmt = {
+        .type = V4L2_BUF_TYPE_VIDEO_OUTPUT
+    };
+    struct video_data *s = s1->priv_data;
+    AVCodecContext *enc;
+    uint32_t v4l2_pixfmt;
+
+    if (s1->flags & AVFMT_FLAG_NONBLOCK)
+        flags |= O_NONBLOCK;
+
+    s->fd = open(s1->filename, flags);
+    if (s->fd < 0) {
+        av_log(s1, AV_LOG_ERROR, "Unable to open V4L2 device '%s'.\n", s1->filename);
+        return AVERROR(errno);
+    }
+
+    if (s1->nb_streams != 1 ||
+        s1->streams[0]->codec->codec_type != AVMEDIA_TYPE_VIDEO ||
+        s1->streams[0]->codec->codec_id   != AV_CODEC_ID_RAWVIDEO) {
+        av_log(s1, AV_LOG_ERROR,
+               "V4L2 output device supports only a single raw video stream.\n");
+        return AVERROR(EINVAL);
+    }
+
+    enc = s1->streams[0]->codec;
+
+    v4l2_pixfmt = avpriv_fmt_ff2v4l(enc->pix_fmt, AV_CODEC_ID_RAWVIDEO);
+    if (!v4l2_pixfmt) { // XXX: try to force them one by one?
+        av_log(s1, AV_LOG_ERROR, "Unknow V4L2 pixel format equivalent for %s\n",
+               av_get_pix_fmt_name(enc->pix_fmt));
+        return AVERROR(EINVAL);
+    }
+
+    if (ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) {
+        res = AVERROR(errno);
+        av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n", av_err2str(res));
+        return res;
+    }
+
+    fmt.fmt.pix.width       = enc->width;
+    fmt.fmt.pix.height      = enc->height;
+    fmt.fmt.pix.pixelformat = v4l2_pixfmt;
+    fmt.fmt.pix.sizeimage   = av_image_get_buffer_size(enc->pix_fmt, enc->width, enc->height, 1);
+
+    if (ioctl(s->fd, VIDIOC_S_FMT, &fmt) < 0) {
+        res = AVERROR(errno);
+        av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_S_FMT): %s\n", av_err2str(res));
+        return res;
+    }
+
+    return res;
+}
+
+static int write_packet(AVFormatContext *s1, AVPacket *pkt)
+{
+    const struct video_data *s = s1->priv_data;
+    write(s->fd, pkt->data, pkt->size);
+    return 0;
+}
+
+static int write_trailer(AVFormatContext *s1)
+{
+    const struct video_data *s = s1->priv_data;
+    close(s->fd);
+    return 0;
+}
+
+AVOutputFormat ff_v4l2_muxer = {
+    .name           = "v4l2",
+    .long_name      = NULL_IF_CONFIG_SMALL("Video4Linux2 device push"),
+    .priv_data_size = sizeof(struct video_data),
+    .audio_codec    = AV_CODEC_ID_NONE,
+    .video_codec    = AV_CODEC_ID_RAWVIDEO,
+    .write_header   = write_header,
+    .write_packet   = write_packet,
+    .write_trailer  = write_trailer,
+    .flags          = AVFMT_NOFILE,
+};
-- 
1.8.2.3



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