vdo-stream.h File Reference

A class representing a stream session. More...

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

Include dependency graph for vdo-stream.h:

Go to the source code of this file.

Functions
VdoStream *	vdo_stream_rgb_new (const VdoMap *settings, guint32 input, VdoResolution resolution, GError **error)
	Create a new RGB24(RGB888) VdoStream (AXIS OS 12.8+). More...
VdoStream *	vdo_stream_nv12_new (const VdoMap *settings, guint32 input, VdoResolution resolution, GError **error)
	Create a new NV12 VdoStream (AXIS OS 12.8+). More...
VdoStream *	vdo_stream_y800_new (const VdoMap *settings, guint32 input, VdoResolution resolution, GError **error)
	Create a new Y800 VdoStream (AXIS OS 12.8+). More...
VdoStream *	vdo_stream_new (VdoMap *settings, VdoBufferFinalizer fin, GError **error)
	Create a new VdoStream. More...
VdoStream *	vdo_stream_get (guint id, GError **error)
	Get an existing video stream. More...
GList *	vdo_stream_get_all (GError **error)
	Get a list of all existing video streams. More...
guint	vdo_stream_get_id (VdoStream *self)
	Return the id of this video stream. More...
gint	vdo_stream_get_fd (VdoStream *self, GError **error)
	Return a file descriptor representing the underlying socket connection. More...
gint	vdo_stream_get_event_fd (VdoStream *self, GError **error)
	Return a file descriptor for prioritized events. More...
VdoMap *	vdo_stream_get_info (VdoStream *self, GError **error)
	Get the info for this video stream. More...
VdoMap *	vdo_stream_get_settings (VdoStream *self, GError **error)
	Get the settings for this video stream. More...
gboolean	vdo_stream_set_settings (VdoStream *self, VdoMap *settings, GError **error)
	Update the settings for this video stream. More...
gboolean	vdo_stream_set_framerate (VdoStream *self, gdouble framerate, GError **error)
	Update the framerate for this video stream. More...
gboolean	vdo_stream_attach (VdoStream *self, VdoMap *intent, GError **error)
	Attach to a Stream. More...
gboolean	vdo_stream_start (VdoStream *self, GError **error)
	Start this video stream. More...
gboolean	vdo_stream_play (VdoStream *self, VdoMap *settings, GError **error)
	Play all buffered video and continue streaming live. More...
void	vdo_stream_stop (VdoStream *self)
	Stop this video stream. More...
gboolean	vdo_stream_force_key_frame (VdoStream *self, GError **error)
	Force this video stream to insert a key frame. More...
VdoBuffer *	vdo_stream_buffer_alloc (VdoStream *self, gpointer opaque, GError **error)
	Allocate a new buffer for this stream. More...
gboolean	vdo_stream_buffer_unref (VdoStream *self, VdoBuffer **buffer, GError **error)
	Decrease the reference count for the specified buffer. More...
gboolean	vdo_stream_buffer_enqueue (VdoStream *self, VdoBuffer *buffer, GError **error)
	Enqueue a buffer for this video stream. More...
VdoBuffer *	vdo_stream_get_buffer (VdoStream *self, GError **error)
	Fetch a VdoBuffer containing a frame. More...
VdoStream *	vdo_stream_to_fd (VdoMap *settings, int data_fd, int meta_fd, GError **error)
	Create and start a new stream to already existing file descriptors. More...
VdoBuffer *	vdo_stream_snapshot (VdoMap *settings, GError **error)
	Fetch a single VdoBuffer containing a frame. More...
VdoMap *	vdo_stream_get_event (VdoStream *self, GError **error)
	Fetch the next Event. More...

Detailed Description

A class representing a stream session.

A VdoStream object is created in order to retrieve, control or monitor a video stream from the VDO service. The object represents video stream, or a sequence of images.

The table below shows the supported settings, which can be used when starting a new stream with vdo_stream_new. These settings can also be read from a stream via vdo_stream_get_settings. Some settings can also be dynamically updated via vdo_stream_set_settings. When a setting is updated, it may appear in the stream's info map as well, to reflect that they have been successfully updated internally in vdo. The info value will differ from the value set by the user, if the value was automatically adjusted to be within a valid range. Always refer to the info map, to see what values are currently used by the stream.

Name	Type	Description
"format"	uint32	Video stream format as VdoFormat.
"buffer.access"	uint32	Access type as VdoBufferAccess
"buffer.count"	uint32	Hint how many in-flight buffers are desired.
"buffer.strategy"	uint32	Buffering Strategy as VdoBufferStrategy.
"input"	uint32	Video input, 1 ... inmax. 0 is invalid. No view areas.
"channel"	uint32	Video channel, 0 is overview, 1, 2, ... are view areas.
"width"	uint32	Video stream horizontal resolution.
"height"	uint32	Video stream vertical resolution.
"framerate"	double	Video stream frame rate.
"compression"	uint32	Video stream compression, Axis standard range [0:100].
"rotation"	uint32	Video stream rotation, normally [0,90,180,270].
"horizontal_flip"	boolean	Video stream horizontal flip (mirroring).
"monochrome"	boolean	Video stream monochrome encoding.
"dynamic.gop"	boolean	Enable dynamic gop
"dynamic.bitrate"	boolean	Enable dynamic bitrate
"dynamic.framerate"	boolean	Enable dynamic framerate
"dynamic.compression"	boolean	Enable dynamic compression
"qp.i"	uint32	QP value for I-frames.
"qp.p"	uint32	QP value for P-frames.
"bitrate"	uint32	Video stream bitrate (bps)
"rc.mode"	uint32	Bitrate control mode as VdoRateControlMode.
"rc.prio"	uint32	Bitrate control priority as VdoRateControlPriority.
"gop_length"	uint32	Video stream GOP length.
"overlays"	string	Enable/disable overlays (off text image application all)
"layers"	boolean	Enable/disable layered stream. Only usable with AV1 encoding
"resolution"	pair32u	Video stream resolution. (AXIS OS 12.4+)
"timestamp.type"	uint16	Deprecated - Removed in AXIS OS 13.
"timestamp.type"	uint32	Select vdo_frame_get_custom_timestamp (AXIS OS 12.4+)
"image.fit"	string	"crop" clips to cover the frame and "scale" shrinks to contain the image (AXIS OS 12.7+ and Artpec-7+)

H.264 Specific Settings

Name	Type	Description
"h264.profile"	uint32	H.264 profile as VdoH264Profile.

H.265 Specific Settings

Name	Type	Description
"h265.profile"	uint32	H.265 profile as VdoH265Profile.

Zipstream Specific Settings

The following Zipstream specific settings are supported for H.264 and H.265 streams.

Name	Type	Description
"zip.strength"	uint32	Zipstream strength. (AXIS OS 11.8) [0,10,20,30,40,50]
"zip.strength"	uint32	Zipstream strength. [0,1,2,4,5,6]->[0,10,20,30,40,50]
"zip.max_gop_length"	uint32	Zipstream maximum GOP length.
"zip.gop_mode"	uint32	Zipstream GOP mode [0 = fixed, 1 = dynamic]
"zip.fps_mode"	uint32	Zipstream framerate control mode: [0 = fixed, 1 = dynamic]
"zip.skip_mode"	uint32	Zipstream frame skip mode: [0 = drop, 1 = empty]
"zip.min_fps_num"	uint32	Zipstream minimum framerate numerator
"zip.min_fps_den"	uint32	Zipstream minimum framerate denominator
"zip.profile"	uint32	Zipstream profile as VdoZipStreamProfile.

ABR Specific Settings

The following ABR specific settings are supported with VDO_RATE_CONTROL_MODE_ABR.

Name	Type	Description
"abr.target_bitrate"	uint32	Stream target bitrate (bps)
"abr.retention_time"	uint32	Retention time in seconds

A VdoStream provides the following info. Info is obtained by calling vdo_stream_get_info().

Name	Type	Description
"subformat"	string	The subformat for streams in YUV or raw format.
"pitch"	uint32	The row stride pitch for streams in YUV or raw format.
"width"	uint32	Actual width of the stream, for yuv and raw streams.
"height"	uint32	Actual height of the stream, for yuv and raw streams.
"initial.q.i"	uint32	Initial QP value for I-frames when the stream started
"initial.q.p"	uint32	Initial QP value for P-frames when the stream started

The vdo_stream_get_info() statistics namespace is deprecated and scheduled for removal in AXIS OS 13.

Name	Type	Description
"statistics.duration"	int64	The duration of the stream in usec.
"statistics.framerate"	uint32	The framerate of the stream.
"statistics.bitrate"	uint32	The bitrate of the stream.
"statistics.frame_count"	uint32	The number of frames read.
"statistics.idrframe_count"	uint32	The number of IDR-frames read.
"statistics.bit_count"	uint32	The number of bits read.
"statistics.failed_frames"	uint32	The number of frames failed to read.
"statistics.accumulated_bytes"	uint64	The number of bytes read since stream start
"statistics.accumulated_idrbytes"	uint64	The number of bytes read from IDR-frames since stream start

Copyright (C) 2016-2025, Axis Communications AB, Lund

Function Documentation

vdo_stream_attach()

gboolean vdo_stream_attach	(	VdoStream *	self,
		VdoMap *	intent,
		GError **	error
	)

Attach to a Stream.

This function is intended to be used with vdo_stream_get, it is redundant to attach to a stream which was created by vdo_stream_new, see vdo_stream_get_event for an example using "intent" with vdo_stream_new.

Parameters

self	A VdoStream.
intent	A VdoMap specifying intent or NULL for VDO_INTENT_DEFAULT.
error	A location to return an error.

Name	Description
VDO_INTENT_CONTROL	Grants start, stop, info, settings, keyframe
VDO_INTENT_CONSUME	The client intends to stream
VDO_INTENT_PRODUCE	The client intends to inject frames
VDO_INTENT_DEFAULT	Grants CONSUME and CONTROL
VDO_INTENT_EVENTFD	Monitor events using file descriptors
VDO_INTENT_UNIVERSE	Everything except VDO_INTENT_EVENTFD

In order to save resources enable as few intents as possible.

g_autoptr(VdoMap)    intent = vdo_map_new();
g_autoptr(VdoStream) stream = vdo_stream_get(id, NULL);
 
vdo_map_set_uint32(intent, "intent", VDO_INTENT_EVENTFD);
 
if (!vdo_stream_attach(stream, intent, &error))
    g_error("Error: %s", error->message);

Returns

TRUE on success, or FALSE on error.

vdo_stream_buffer_alloc()

VdoBuffer* vdo_stream_buffer_alloc	(	VdoStream *	self,
		gpointer	opaque,
		GError **	error
	)

Allocate a new buffer for this stream.

Invoke this function in order to allocate a new buffer for this video stream. The vdo service performs the actual memory allocation and owns the buffer. A handle to the allocated buffer is returned in the form of a VdoBuffer.

Note

• This function is synchronous and will block until a response from the vdo service is received.
• This function can only be invoked for non-encoded video streams.

Parameters

self	A VdoStream.
opaque	A user data pointer.
error	A location to return an error.

Returns

A VdoBuffer on success, or NULL on error.

vdo_stream_buffer_enqueue()

gboolean vdo_stream_buffer_enqueue	(	VdoStream *	self,
		VdoBuffer *	buffer,
		GError **	error
	)

Enqueue a buffer for this video stream.

Invoking this function equeues the specified VdoBuffer in the internal queue of this video stream in order to be subsequently filled with frame data.

Parameters

self	A VdoStream.
buffer	A VdoBuffer.
error	A location to return an error.

Returns

TRUE on success, or FALSE on error.

vdo_stream_buffer_unref()

gboolean vdo_stream_buffer_unref	(	VdoStream *	self,
		VdoBuffer **	buffer,
		GError **	error
	)

Decrease the reference count for the specified buffer.

The buffer is freed by the vdo service when the reference count reaches 0.

Note

• This function is synchronous and will block until a response from the vdo service is received.

Parameters

self	A VdoStream.
buffer	A pointer to a VdoBuffer pointer.
error	A location to return an error.

Returns

TRUE on success, or FALSE on error.

vdo_stream_force_key_frame()

gboolean vdo_stream_force_key_frame	(	VdoStream *	self,
		GError **	error
	)

Force this video stream to insert a key frame.

This function is invoked in order to force a key frame into a video stream. Invoking this functionon a video stream with a format that is not a video format (e.g. H.264 or H.265) will have no effect.

Parameters

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

Returns

TRUE on success, or FALSE on error.

vdo_stream_get()

VdoStream* vdo_stream_get	(	guint	id,
		GError **	error
	)

Get an existing video stream.

Create a new VdoStream object representing an existing video stream session with the specified id.

Parameters

id	A video stream id
error	A location to return an error.

Returns

A VdoStream, or NULL on error. Free with g_clear_object().

vdo_stream_get_all()

GList* vdo_stream_get_all

(

GError **

error

)

Get a list of all existing video streams.

Create new VdoStream objects representing each existing video stream session 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_stream_get_buffer()

VdoBuffer* vdo_stream_get_buffer	(	VdoStream *	self,
		GError **	error
	)

Fetch a VdoBuffer containing a frame.

Stream global settings which control the behavior of this function: "socket.blocking" (default: TRUE) "socket.timeout_ms"

The following errors are transient: VDO_ERROR_NO_DATA Recover by fetching the next buffer. The following errors are expected to occur during maintenance: VDO_ERROR_INTERFACE_DOWN Recover by waiting for the service to restart. Complete VdoStream reinitialization is necessary. All remaining errors are fatal: Complete VdoStream reinitialization is necessary.

Parameters

self	A VdoStream
error	Location to store an error or NULL.

Returns

A VdoBuffer, or NULL on error. Free with vdo_stream_buffer_unref().

vdo_stream_get_event()

VdoMap* vdo_stream_get_event	(	VdoStream *	self,
		GError **	error
	)

Fetch the next Event.

This function is always non-blocking, it is intended to be used together with vdo_stream_get_event_fd and poll to detect when new events occur.

See VdoStreamEvent for the list of possible events, the current event is returned in the VdoMap "event" field.

The following errors are transient: VDO_ERROR_NO_EVENT The equivalent of EAGAIN, i.e. there's currently no event. The following errors are expected to occur during maintenance: VDO_ERROR_INTERFACE_DOWN Recover by waiting for the service to restart. Complete VdoStream reinitialization is necessary. All remaining errors are fatal: Complete VdoStream reinitialization is necessary.

g_autoptr(VdoMap) settings = vdo_map_new();
vdo_map_set_uint32(settings, "intent", VDO_INTENT_DEFAULT | VDO_INTENT_EVENTFD);
 
g_autoptr(VdoStream) stream = vdo_stream_new(settings, NULL, &error);
if (!stream)
  return;
 
if (!vdo_stream_start(stream, &error))
  return;
 
int fd = vdo_stream_get_fd(stream, &error);
if (fd < 0)
  return;
 
struct pollfd fds = {
  .fd = fd,
  .events = POLL_IN,
 };
 
while (1) {
  if (poll(&fds, 1, -1) < 1)
    return;
 
  g_autoptr(VdoMap) event = vdo_stream_get_event(stream, &error);
  if (!event)
    return;
  switch(vdo_map_get_uint32(event, "event", VDO_STREAM_EVENT_NONE)) {
  case VDO_STREAM_EVENT_STARTED: break;
  case VDO_STREAM_EVENT_STOPPED: break;
  default: break;
  }
}

Parameters

self	A VdoStream
error	Location to store an error or NULL.

Returns

A VdoMap, or NULL on error. Free with g_clear_object().

vdo_stream_get_event_fd()

gint vdo_stream_get_event_fd	(	VdoStream *	self,
		GError **	error
	)

Return a file descriptor for prioritized events.

This requires VDO_INTENT_EVENTFD and is intended to be used together with the vdo_stream_get_event function.

Parameters

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

Returns

A file descriptor, or -1 on error.

vdo_stream_get_fd()

gint vdo_stream_get_fd	(	VdoStream *	self,
		GError **	error
	)

Return a file descriptor representing the underlying socket connection.

The file descriptor returned by this function represents the underlying socket based connection to the vdo service. The returned file descriptor can by used as an event source in an event loop to handle asynchronous I/O events.

Parameters

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

Returns

A file descriptor, or -1 on error.

vdo_stream_get_id()

guint vdo_stream_get_id

(

VdoStream *

self

)

Return the id of this video stream.

Parameters

self	A VdoStream

Returns

A video stream id.

vdo_stream_get_info()

VdoMap* vdo_stream_get_info	(	VdoStream *	self,
		GError **	error
	)

Get the info for this video stream.

This function is called in order to get a pointer to the info map for this video stream. 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_stream_get_info(stream, &error);
guint value = vdo_map_get_uint32(info, "name", 0);

Parameters

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

Returns

A pointer to a VdoMap owned by this video stream, or NULL on error. Free with g_clear_object().

vdo_stream_get_settings()

VdoMap* vdo_stream_get_settings	(	VdoStream *	self,
		GError **	error
	)

Get the settings for this video stream.

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

g_autoptr(VdoMap) settings = vdo_stream_get_settings(stream, &error);
guint value = vdo_map_get_uint32(settings, "name", 0);

Parameters

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

Returns

A pointer to a VdoMap owned by this video stream, or NULL on error. Free with g_clear_object().

vdo_stream_new()

VdoStream* vdo_stream_new	(	VdoMap *	settings,
		VdoBufferFinalizer	fin,
		GError **	error
	)

Create a new VdoStream.

Create a new VdoStream object representing a video stream session.

Parameters

settings	A VdoMap containing settings for the new video stream.
fin	The VdoBufferFinalizer is called before buffers are finalized.
error	A location to return an error.

Returns

A VdoStream, or NULL on error. Free with g_clear_object().

vdo_stream_nv12_new()

VdoStream* vdo_stream_nv12_new	(	const VdoMap *	settings,
		guint32	input,
		VdoResolution	resolution,
		GError **	error
	)

Create a new NV12 VdoStream (AXIS OS 12.8+).

Creates a new NV12 VdoStream object representing a video stream session.

Unlike vdo_stream_new(), this API enables automatic framerate adjustment (to disable this feature, you need to explicitly specify the framerate). In addition, it applies several other defaults suitable for video analytics. It's still possible to override options such as 'buffer.count' or 'image.fit'.

// This convenience API is roughly equivalent to:
g_autoptr(GError) error = nullptr;
g_autoptr(VdoMap) settings = vdo_map_new();
vdo_map_set_boolean(settings, "socket.blocking", false);
vdo_map_set_string(settings,  "image.fit", "scale");
vdo_map_set_uint32(settings,  "buffer.count", 2u);
vdo_map_set_uint32(settings,  "format", VDO_FORMAT_YUV);
vdo_map_set_string(settings,  "subformat", "NV12");
vdo_map_set_uint32(settings,  "input", ...);
vdo_map_set_pair32u(settings, "resolution", ...);
vdo_stream_new(settings, nullptr, &error);

Parameters

settings	A VdoMap containing optional overrides or NULL for default.
input	The source of the stream (typically a sensor).
resolution	The desired resolution of the stream.
error	A location to store an error, or NULL.

Returns

A pointer to a VdoStream object, or NULL on error. Free with g_clear_object().

vdo_stream_play()

gboolean vdo_stream_play	(	VdoStream *	self,
		VdoMap *	settings,
		GError **	error
	)

Play all buffered video and continue streaming live.

This function is invoked in order to play buffered video, it requires an already started buffering stream.

Parameters

self	A VdoStream.
settings	A VdoMap controlling play or NULL for default.
error	A location to return an error.

Returns

TRUE on success, or FALSE on error.

vdo_stream_rgb_new()

VdoStream* vdo_stream_rgb_new	(	const VdoMap *	settings,
		guint32	input,
		VdoResolution	resolution,
		GError **	error
	)

Create a new RGB24(RGB888) VdoStream (AXIS OS 12.8+).

Creates a new RGB24(RGB888) VdoStream object representing a video stream session.

Unlike vdo_stream_new(), this API enables automatic framerate adjustment (to disable this feature, you need to explicitly specify the framerate). In addition, it applies several other defaults suitable for video analytics. It's still possible to override options such as 'buffer.count', 'image.fit', or switch to VDO_FORMAT_PLANAR_RGB "format".

// This convenience API is roughly equivalent to:
g_autoptr(GError) error = nullptr;
g_autoptr(VdoMap) settings = vdo_map_new();
vdo_map_set_boolean(settings, "socket.blocking", false);
vdo_map_set_string(settings,  "image.fit", "scale");
vdo_map_set_uint32(settings,  "buffer.count", 2u);
vdo_map_set_uint32(settings,  "format", VDO_FORMAT_RGB);
vdo_map_set_uint32(settings,  "input", ...);
vdo_map_set_pair32u(settings, "resolution", ...);
vdo_stream_new(settings, nullptr, &error);

Parameters

settings	A VdoMap containing optional overrides or NULL for default.
input	The source of the stream (typically a sensor).
resolution	The desired resolution of the stream.
error	A location to store an error, or NULL.

Returns

A pointer to a VdoStream object, or NULL on error. Free with g_clear_object().

vdo_stream_set_framerate()

gboolean vdo_stream_set_framerate	(	VdoStream *	self,
		gdouble	framerate,
		GError **	error
	)

Update the framerate for this video stream.

This function is invoked in order to update the framerate of a video stream. For this API to be used, the stream needs one or more of the following stream settings to be applied before the stream is started:

1) Dynamic framerate is enabled (dynamic.framerate = TRUE) 2) Zipstream fps mode is set to dynamic (zip.fps_mode = 1)

gdouble framerate = 30.0;
if (!vdo_stream_set_framerate(stream, framerate, &error))
    g_error("Error: %s", error->message);

Parameters

self	A VdoStream.
framerate	A framerate.
error	A location to return an error.

Returns

TRUE on success, or FALSE on error.

vdo_stream_set_settings()

gboolean vdo_stream_set_settings	(	VdoStream *	self,
		VdoMap *	settings,
		GError **	error
	)

Update the settings for this video stream.

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

g_autoptr(VdoMap) settings = vdo_map_new();
vdo_map_set_uint32(settings, "name", value);
if (!vdo_stream_set_settings(stream, settings, &error))
    g_error("Error: %s", error->message);

Parameters

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

Returns

TRUE on success, or FALSE on error.

vdo_stream_snapshot()

VdoBuffer* vdo_stream_snapshot	(	VdoMap *	settings,
		GError **	error
	)

Fetch a single VdoBuffer containing a frame.

Convenience function for fetching a single frame. The setup and teardown overhead is too high for continuous streaming.

Free the buffer with g_autoptr or g_clear_object.

g_autoptr(VdoMap)  settings = vdo_map_new();
vdo_map_set_uint32(settings, "format", VDO_FORMAT_JPEG);
 
g_autoptr(VdoBuffer) buffer = vdo_stream_snapshot(settings, NULL);

Parameters

settings	A map of stream settings
error	Location to store an error or NULL.

Returns

A VdoBuffer, or NULL on error. Free with g_clear_object().

vdo_stream_start()

gboolean vdo_stream_start	(	VdoStream *	self,
		GError **	error
	)

Start this video stream.

This function is invoked in order to start a video stream.

Parameters

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

Returns

TRUE on success, or FALSE on error.

vdo_stream_stop()

void vdo_stream_stop

(

VdoStream *

self

)

Stop this video stream.

This function is invoked in order to stop a video stream.

Parameters

self	A VdoStream.

vdo_stream_to_fd()

VdoStream* vdo_stream_to_fd	(	VdoMap *	settings,
		int	data_fd,
		int	meta_fd,
		GError **	error
	)

Create and start a new stream to already existing file descriptors.

This is a convenience function without VdoBuffer support, instead the stream will output data and metadata to two separate file descriptors.

NOTE: metadata is not implemented yet, set meta_fd to -1.

When done with the stream, free it with g_clear_object before closing the file descriptors.

Parameters

settings	A map of stream settings
data_fd	An fd to send stream data
meta_fd	An fd to send stream metadata
error	Location to store an error or NULL.

Returns

A VdoStream, or NULL on error. Free with g_clear_object().

vdo_stream_y800_new()

VdoStream* vdo_stream_y800_new	(	const VdoMap *	settings,
		guint32	input,
		VdoResolution	resolution,
		GError **	error
	)

Create a new Y800 VdoStream (AXIS OS 12.8+).

Creates a new Y800 VdoStream object representing a video stream session.

Unlike vdo_stream_new(), this API enables automatic framerate adjustment (to disable this feature, you need to explicitly specify the framerate). In addition, it applies several other defaults suitable for video analytics. It's still possible to override options such as 'buffer.count' or 'image.fit'.

// This convenience API is roughly equivalent to:
g_autoptr(GError) error = nullptr;
g_autoptr(VdoMap) settings = vdo_map_new();
vdo_map_set_boolean(settings, "socket.blocking", false);
vdo_map_set_string(settings,  "image.fit", "scale");
vdo_map_set_uint32(settings,  "buffer.count", 2u);
vdo_map_set_uint32(settings,  "format", VDO_FORMAT_YUV);
vdo_map_set_string(settings,  "subformat", "Y800");
vdo_map_set_uint32(settings,  "input", ...);
vdo_map_set_pair32u(settings, "resolution", ...);
vdo_stream_new(settings, nullptr, &error);

Parameters

settings	A VdoMap containing optional overrides or NULL for default.
input	The source of the stream (typically a sensor).
resolution	The desired resolution of the stream.
error	A location to store an error, or NULL.

Returns

A pointer to a VdoStream object, or NULL on error. Free with g_clear_object().