vdo-channel.h File Reference

A class representing a channel. More...

#include "vdo-map.h"
#include "vdo-types.h"
#include <unistd.h>
#include <glib-object.h>

Include dependency graph for vdo-channel.h:

Go to the source code of this file.

Macros
#define	VDO_CHANNEL_GLOBAL   NULL
	Used for accessing info which is global for all channels.

Functions
VdoChannel *	vdo_channel_get (guint channel_nbr, GError **error)
	Get an existing channel. More...
VdoChannel *	vdo_channel_get_ex (VdoMap *desc, GError **error)
	Get an existing channel matching a description. More...
GList *	vdo_channel_get_all (GError **error)
	Gets all existing channels. More...
GList *	vdo_channel_get_filtered (VdoMap *filter, GError **error)
	Gets all existing channels matching a filter. More...
VdoMap *	vdo_channel_get_info (VdoChannel *self, GError **error)
	Get the info for this channel. More...
VdoMap *	vdo_channel_get_settings (VdoChannel *self, GError **error)
	Get the settings for this channel. More...
gboolean	vdo_channel_set_settings (VdoChannel *self, VdoMap *settings, GError **error)
	Update the settings for this channel. More...
VdoMap *	vdo_channel_get_stream_profile (VdoChannel *self, const gchar *profile, VdoFormat format, GError **error)
	Query stream profile for the specified name, format and channel. More...
VdoResolutionSet *	vdo_channel_get_resolutions (VdoChannel *self, VdoMap *filter, GError **error)
	Fetch all valid resolutions for a channel with specified stream format. More...
guint	vdo_channel_get_id (VdoChannel *self)

Detailed Description

A class representing a channel.

A VdoChannel object is created in order to retrieve or control a video channel from the Vdo video service.

A VdoChannel represents the video from one sensor, or several sensors combined into a composite view. Every vdo stream has a channel as its source.

A VdoChannel supports the following generic settings. Settings are accessed by calling vdo_channel_get_settings() and vdo_channel_set_settings().

Deprecated:

Crop Settings

Name	Type	Description
"crop.max_width"	uint32	The width of the buffer we crop from, (crop.x + crop.width must be less than this)
"crop.max_height"	uint32	The height of the buffer we crop from, (crop.y + crop.height must be less than this)
"crop.x"	uint32	The x position of the crop
"crop.y"	uint32	The y position of the crop
"crop.width"	uint32	The width of the crop
"crop.height"	uint32	The height of the crop

Deprecated:

User video settings

Name	Type	Description
"yuv.input.path"	string	Path to user video input file

A VdoChannel provides the following info. Info is obtained by calling vdo_channel_get_info().

Name	Type	Description
"mirror.possible"	boolean	Whether mirroring is possible on this channel
"crop.possible"	boolean	Whether crop is possible on this channel
"dptz.possible"	boolean	Whether dptz is possible on this channel
"available_rotations"	string	Available rotations for this channel

Copyright (C) 2016-2024, Axis Communications AB, Lund

Function Documentation

vdo_channel_get()

VdoChannel* vdo_channel_get	(	guint	channel_nbr,
		GError **	error
	)

Get an existing channel.

Create a new VdoChannel object representing an existing channel session with the specified channel number.

Parameters

channel_nbr	A channel number
error	A location to return an error.

Returns

A VdoChannel or NULL on error. Free with g_object_unref().

vdo_channel_get_all()

GList* vdo_channel_get_all

(

GError **

error

)

Gets all existing channels.

Create new VdoChannel objects representing each existing channel and return those in a GList.

Parameters

error

A location to return an error.

Returns

A GList containing VdoStream objects or NULL on error. Free with g_list_free_full(list, g_object_unref).

vdo_channel_get_ex()

VdoChannel* vdo_channel_get_ex	(	VdoMap *	desc,
		GError **	error
	)

Get an existing channel matching a description.

Create a new VdoChannel object representing an existing channel session matching a description.

The description map must contain exactly one the following keys:

• view
• warp
• input
• channel
• virtual (deprecated)

where the value is the suffix for the specified type.

For example, get channel object for 'input1':

g_autoptr(VdoMap) desc = vdo_map_new();
vdo_map_set_uint32(desc, "input", 1);
 
g_autoptr(VdoChannel) channel = vdo_channel_get_ex(desc, &error);

Parameters

desc	A VdoMap specifying a description.
error	A location to return an error.

Returns

A VdoChannel or NULL on error. Free with g_object_unref() or g_autoptr.

vdo_channel_get_filtered()

GList* vdo_channel_get_filtered	(	VdoMap *	filter,
		GError **	error
	)

Gets all existing channels matching a filter.

Create new VdoChannel objects representing existing channels matching a filter and return those in a GList.

Parameters

filter	A VdoMap specifying filter or NULL for all channels.
error	A location to return an error.

Returns

A GList containing VdoStream objects or NULL on error. Free with g_list_free_full(list, g_object_unref).

vdo_channel_get_id()

guint vdo_channel_get_id

(

VdoChannel *

self

)

vdo_channel_get_id:

Parameters

self	The VdoChannel to query.

Returns: The id of the channel

vdo_channel_get_info()

VdoMap* vdo_channel_get_info	(	VdoChannel *	self,
		GError **	error
	)

Get the info for this channel.

This function is called in order to get a pointer to the info map for this channel. The returned pointer is a pointer to a newly allocated VdoMap owned by the caller of this function. For example:

g_autoptr(VdoMap) info = vdo_channel_get_info(channel, &error);
guint value = vdo_map_get_uint32(info, "name", 0);

AXIS OS 12.1 supports VDO_CHANNEL_GLOBAL with the following info.

Name	Type	Description
"view.count"	uint32	The amount of view area channels
"warp.count"	uint32	The amount of warp/dewarp channels
"input.count"	uint32	The amount of sensor/input channels
"channel.count"	uint32	The total channel count

// AXIS OS 12.1
g_autoptr(VdoMap) info = vdo_channel_get_info(VDO_CHANNEL_GLOBAL, &error);
guint view_count    = vdo_map_get_uint32(info, "view.count", 0);
guint warp_count    = vdo_map_get_uint32(info, "warp.count", 0);
guint input_count   = vdo_map_get_uint32(info, "input.count", 0);
guint channel_count = vdo_map_get_uint32(info, "channel.count", 0);

Parameters

self	A VdoChannel.
error	A location to return an error.

Returns

A pointer to a VdoMap owned by this channel, or NULL if error is set. Free with g_object_unref().

vdo_channel_get_resolutions()

VdoResolutionSet* vdo_channel_get_resolutions	(	VdoChannel *	self,
		VdoMap *	filter,
		GError **	error
	)

Fetch all valid resolutions for a channel with specified stream format.

Get a VdoResolutionSet of valid resolutions.

Parameters

self	The VdoChannel to query.
error	A location to return an error.
filter	A VdoMap specifying filter or NULL for default.

Name	Type	Description
"format"	uint32	Video stream format as VdoFormat.
"subformat"	string	The subformat for streams in YUV format.
"select"	string	Supports: "all", "min", "max", "minmax".
"aspect_ratio"	string	Supports: "1:1", "4:3", "5:4", "16:9", "16:10", "native".
"pixel.limit"	uint32	The default pixel limit is tuned per platform (YUV Only).

Returns

A VdoResolutionSet on success. NULL if error is set. Free with g_free.

vdo_channel_get_settings()

VdoMap* vdo_channel_get_settings	(	VdoChannel *	self,
		GError **	error
	)

Get the settings for this channel.

This function is called in order to get a pointer to the settings map for this channel. The returned pointer is a pointer to a newly allocated VdoMap owned by the caller of this function. For example:

VdoMap* settings = vdo_channel_get_settings(channel, &error);
guint value = vdo_map_get_uint32(settings, "name", 0);
g_object_unref(settings);

Parameters

self	A VdoChannel.
error	A location to return an error.

Returns

A pointer to a VdoMap owned by this channel, or NULL if error is set. Free with g_object_unref().

vdo_channel_get_stream_profile()

VdoMap* vdo_channel_get_stream_profile	(	VdoChannel *	self,
		const gchar *	profile,
		VdoFormat	format,
		GError **	error
	)

Query stream profile for the specified name, format and channel.

The combination of profile and format is unique and may have different stream settings.

Parameters

self	The VdoChannel to query.
profile	The name of the stream profile
format	The format of the stream profile.
error	A location to return an error.

Returns

A pointer to a VdoMap with profile settings, or NULL if error is set. Free with g_object_unref().

vdo_channel_set_settings()

gboolean vdo_channel_set_settings	(	VdoChannel *	self,
		VdoMap *	settings,
		GError **	error
	)

Update the settings for this channel.

This function is invoked in order to update the settings of a channel. The caller owns the VdoMap containing the new/updated settings.

VdoMap* settings = vdo_map_new();
vdo_map_set_uint32(settings, "name", value);
if (!vdo_channel_set_settings(channel, settings, &error)) {
    g_error("Error: %s", error->message);
}
g_object_unref(settings);

Parameters

self	A VdoChannel.
settings	A VdoMap containing new/updated settings.
error	A location to return an error.

Returns

TRUE on success, FALSE if error is set.