Nicolas Dufresne a007e2dd9d v4l2codecs: Add skeleton of H264 decoder
This introduces the skeleton of the H264 decoder. The plugin will list the
devices and register a subclass of the GstV4L2CodecH264Dec base class. The
subclass will pick the required specific information from the GstV4L2Device
stored in the subclass structure.
2020-03-31 09:34:05 -04:00

215 lines
5.6 KiB
C

/* GStreamer
* Copyright (C) 2020 Nicolas Dufresne <nicolas.dufresne@collabora.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "gstv4l2decoder.h"
#include "linux/media.h"
#include "linux/videodev2.h"
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
GST_DEBUG_CATEGORY (v4l2_decoder_debug);
#define GST_CAT_DEFAULT v4l2_decoder_debug
enum
{
PROP_0,
PROP_MEDIA_DEVICE,
PROP_VIDEO_DEVICE,
};
struct _GstV4l2Decoder
{
GstObject parent;
gboolean opened;
gint media_fd;
gint video_fd;
/* properties */
gchar *media_device;
gchar *video_device;
};
G_DEFINE_TYPE_WITH_CODE (GstV4l2Decoder, gst_v4l2_decoder, GST_TYPE_OBJECT,
GST_DEBUG_CATEGORY_INIT (v4l2_decoder_debug, "v4l2codecs-decoder", 0,
"V4L2 stateless decoder helper"));
static void
gst_v4l2_decoder_finalize (GObject * obj)
{
GstV4l2Decoder *self = GST_V4L2_DECODER (obj);
if (self->media_fd)
close (self->media_fd);
if (self->video_fd)
close (self->media_fd);
g_free (self->media_device);
g_free (self->video_device);
G_OBJECT_CLASS (gst_v4l2_decoder_parent_class)->finalize (obj);
}
static void
gst_v4l2_decoder_init (GstV4l2Decoder * self)
{
}
static void
gst_v4l2_decoder_class_init (GstV4l2DecoderClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
gobject_class->finalize = gst_v4l2_decoder_finalize;
gobject_class->get_property = gst_v4l2_decoder_get_property;
gobject_class->set_property = gst_v4l2_decoder_set_property;
gst_v4l2_decoder_install_properties (gobject_class, 0, NULL);
}
GstV4l2Decoder *
gst_v4l2_decoder_new (GstV4l2CodecDevice * device)
{
GstV4l2Decoder *decoder;
g_return_val_if_fail (device->function == MEDIA_ENT_F_PROC_VIDEO_DECODER,
NULL);
decoder = g_object_new (GST_TYPE_V4L2_DECODER,
"media-device", device->media_device_path,
"video-device", device->video_device_path, NULL);
return gst_object_ref_sink (decoder);
}
gboolean
gst_v4l2_decoder_open (GstV4l2Decoder * self)
{
self->media_fd = open (self->media_device, 0);
if (self->media_fd < 0) {
GST_ERROR_OBJECT (self, "Failed to open '%s': %s",
self->media_device, g_strerror (errno));
return FALSE;
}
self->video_fd = open (self->video_device, 0);
if (self->video_fd < 0) {
GST_ERROR_OBJECT (self, "Failed to open '%s': %s",
self->video_device, g_strerror (errno));
return FALSE;
}
self->opened = TRUE;
return TRUE;
}
gboolean
gst_v4l2_decoder_enum_sink_fmt (GstV4l2Decoder * self, gint i,
guint32 * out_fmt)
{
struct v4l2_fmtdesc fmtdesc = { i, V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE, };
gint ret;
g_return_val_if_fail (self->opened, FALSE);
ret = ioctl (self->video_fd, VIDIOC_ENUM_FMT, &fmtdesc);
if (ret < 0) {
if (errno != EINVAL)
GST_ERROR_OBJECT (self, "VIDIOC_ENUM_FMT failed: %s", g_strerror (errno));
return FALSE;
}
GST_DEBUG_OBJECT (self, "Found format %" GST_FOURCC_FORMAT " (%s)",
GST_FOURCC_ARGS (fmtdesc.pixelformat), fmtdesc.description);
*out_fmt = fmtdesc.pixelformat;
return TRUE;
}
void
gst_v4l2_decoder_install_properties (GObjectClass * gobject_class,
gint prop_offset, GstV4l2CodecDevice * device)
{
const gchar *media_device_path = NULL;
const gchar *video_device_path = NULL;
if (device) {
media_device_path = device->media_device_path;
video_device_path = device->video_device_path;
}
g_object_class_install_property (gobject_class, PROP_MEDIA_DEVICE,
g_param_spec_string ("media-device", "Media Device Path",
"Path to the media device node", media_device_path,
G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_VIDEO_DEVICE,
g_param_spec_string ("video-device", "Video Device Path",
"Path to the video device node", video_device_path,
G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
}
void
gst_v4l2_decoder_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstV4l2Decoder *self = GST_V4L2_DECODER (object);
switch (prop_id) {
case PROP_MEDIA_DEVICE:
g_free (self->media_device);
self->media_device = g_value_dup_string (value);
break;
case PROP_VIDEO_DEVICE:
g_free (self->video_device);
self->video_device = g_value_dup_string (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
void
gst_v4l2_decoder_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstV4l2Decoder *self = GST_V4L2_DECODER (object);
switch (prop_id) {
case PROP_MEDIA_DEVICE:
g_value_set_string (value, self->media_device);
break;
case PROP_VIDEO_DEVICE:
g_value_set_string (value, self->video_device);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}