Outputs allow the ability to output the currently rendering audio/video. Streaming and recording are two common examples of outputs, but not the only types of outputs. Outputs can receive the raw data or receive encoded data. The libobs/obs-output.h file is the dedicated header for implementing outputs
.. type:: obs_output_t A reference-counted output object.
.. type:: obs_weak_output_t A weak reference to an output object.
#include <obs.h>.. type:: struct obs_output_info Output definition structure.
.. member:: const char *obs_output_info.id Unique string identifier for the source (required).
.. member:: uint32_t obs_output_info.flags
Output capability flags (required).
(Author's note: This should be renamed to "capability_flags")
A bitwise OR combination of one or more of the following values:
- **OBS_OUTPUT_VIDEO** - Can output video.
- **OBS_OUTPUT_AUDIO** - Can output audio.
- **OBS_OUTPUT_AV** - Combines OBS_OUTPUT_VIDEO and OBS_OUTPUT_AUDIO.
- **OBS_OUTPUT_ENCODED** - Output is encoded.
When this capability flag is used, the output must have encoders
assigned to it via the :c:func:`obs_output_set_video_encoder()`
and/or :c:func:`obs_output_set_audio_encoder()` functions in order
to be started.
- **OBS_OUTPUT_SERVICE** - Output requires a service object.
When this capability flag is used, the output must have a service
assigned to it via the :c:func:`obs_output_set_service()` function
in order to be started.
This is usually used with live streaming outputs that stream to
specific services.
- **OBS_OUTPUT_MULTI_TRACK** - Output supports multiple audio tracks.
When this capability flag is used, specifies that this output
supports multiple encoded audio tracks simultaneously.
- **OBS_OUTPUT_CAN_PAUSE** - Output supports pausing.
When this capability flag is used, the output supports pausing.
When an output is paused, raw or encoded audio/video data will be
halted when paused down to the exact point to the closest video
frame. Audio data will be correctly truncated down to the exact
audio sample according to that video frame timing.
.. member:: const char *(*obs_output_info.get_name)(void *type_data) Get the translated name of the output type. :param type_data: The type_data variable of this structure :return: The translated name of the output type
.. member:: void *(*obs_output_info.create)(obs_data_t *settings, obs_output_t *output) Creates the implementation data for the output. :param settings: Settings to initialize the output with :param output: Output that this data is associated with :return: The implementation data associated with this output
.. member:: void (*obs_output_info.destroy)(void *data) Destroys the implementation data for the output.
.. member:: bool (*obs_output_info.start)(void *data)
Starts the output. If needed, this function can spawn a thread,
return *true* immediately, and then signal for failure later.
:return: *true* if successful or deferring to a signal to indicate
failure, *false* on failure to start
.. member:: void (*obs_output_info.stop)(void *data, uint64_t ts)
Requests an output to stop at a specified time. The *ts* parameter
indicates when the stop should occur. Output will actually stop when
either the :c:func:`obs_output_end_data_capture()` or
:c:func:`obs_output_signal_stop()` functions are called. If *ts* is
0, an immediate stop was requested.
:param ts: The timestamp to stop. If 0, the output should attempt to
stop immediately rather than wait for any more data to
process
.. member:: void (*obs_output_info.raw_video)(void *data, struct video_data *frame) This is called when the output receives raw video data. Only applies to outputs that are not encoded. :param frame: The raw video frame
.. member:: void (*obs_output_info.raw_audio)(void *data, struct audio_data *frames) This is called when the output receives raw audio data. Only applies to outputs that are not encoded. **This callback must be used with single-track raw outputs.** :param frames: The raw audio frames
.. member:: void (*obs_output_info.raw_audio2)(void *data, size_t idx, struct audio_data *frames) This is called when the output receives raw audio data. Only applies to outputs that are not encoded. **This callback must be used with multi-track raw outputs.** :param idx: The audio track index :param frames: The raw audio frames
.. member:: void (*obs_output_info.encoded_packet)(void *data, struct encoder_packet *packet)
This is called when the output receives encoded video/audio data.
Only applies to outputs that are encoded. Packets will always be
given in monotonic timestamp order.
:param packet: The video or audio packet. If NULL, an encoder error
occurred, and the output should call
:c:func:`obs_output_signal_stop()` with the error code
**OBS_OUTPUT_ENCODE_ERROR**.
.. member:: void (*obs_output_info.update)(void *data, obs_data_t *settings) Updates the settings for this output. (Optional) :param settings: New settings for this output
.. member:: void (*obs_output_info.get_defaults)(obs_data_t *settings)
void (*obs_output_info.get_defaults2)(void *type_data, obs_data_t *settings)
Sets the default settings for this output.
(Optional)
:param settings: Default settings. Call obs_data_set_default*
functions on this object to set default setting
values
.. member:: obs_properties_t *(*obs_output_info.get_properties)(void *data)
obs_properties_t *(*obs_output_info.get_properties2)(void *data, void *type_data)
Gets the property information of this output.
(Optional)
:return: The properties of the output
.. member:: void (*obs_output_info.unused1)(void *data) This callback is no longer used.
.. member:: uint64_t (*obs_output_info.get_total_bytes)(void *data) Returns the number of total bytes processed by this output. (Optional) :return: Total bytes processed by this output since it started
.. member:: int (*obs_output_info.get_dropped_frames)(void *data)
Returns the number of dropped frames.
(Optional)
:return: Number of dropped frames due to network congestion by this
output since it started
.. member:: void *obs_output_info.type_data
void (*obs_output_info.free_type_data)(void *type_data)
Private data associated with this entry. Note that this is not the
same as the implementation data; this is used to differentiate
between two different types if the same callbacks are used for more
than one different type.
(Optional)
.. member:: float (*obs_output_info.get_congestion)(void *data) This function is used to indicate how currently congested the output is. Useful for visualizing how much data is backed up on streaming outputs. (Optional) :return: Current congestion value (0.0f..1.0f)
.. member:: int (*obs_output_info.get_connect_time_ms)(void *data) This function is used to determine how many milliseconds it took to connect to its current server. (Optional) :return: Milliseconds it took to connect to its current server
.. member:: const char *obs_output_info.encoded_video_codecs
const char *obs_output_info.encoded_audio_codecs
This variable specifies which codecs are supported by an encoded
output, separated by semicolon.
(Optional, though recommended)
start (ptr output)
Called when the output starts.
stop (ptr output, int code)
Called when the output stops.
Parameters:
- code - Can be one of the following values:
OBS_OUTPUT_SUCCESS - Successfully stoppedOBS_OUTPUT_BAD_PATH - The specified path was invalidOBS_OUTPUT_CONNECT_FAILED - Failed to connect to a serverOBS_OUTPUT_INVALID_STREAM - Invalid stream pathOBS_OUTPUT_ERROR - Generic errorOBS_OUTPUT_DISCONNECTED - Unexpectedly disconnectedOBS_OUTPUT_UNSUPPORTED - The settings, video/audio format, or codecs are unsupported by this outputOBS_OUTPUT_NO_SPACE - Ran out of disk spaceOBS_OUTPUT_ENCODE_ERROR - Encoder error
pause (ptr output)
Called when the output has been paused.
unpause (ptr output)
Called when the output has been unpaused.
starting (ptr output)
Called when the output is starting.
stopping (ptr output)
Called when the output is stopping.
activate (ptr output)
Called when the output activates (starts capturing data).
deactivate (ptr output)
Called when the output deactivates (stops capturing data).
reconnect (ptr output)
Called when the output is reconnecting.
reconnect_success (ptr output)
Called when the output has successfully reconnected.
.. function:: void obs_register_output(struct obs_output_info *info) Registers an output type. Typically used in :c:func:`obs_module_load()` or in the program's initialization phase.
.. function:: const char *obs_output_get_display_name(const char *id) Calls the :c:member:`obs_output_info.get_name` callback to get the translated display name of an output type. :param id: The output type string identifier :return: The translated display name of an output type
.. function:: obs_output_t *obs_output_create(const char *id, const char *name, obs_data_t *settings, obs_data_t *hotkey_data)
Creates an output with the specified settings.
The "output" context is used for anything related to outputting the
final video/audio mix (E.g. streaming or recording). Use
obs_output_release to release it.
:param id: The output type string identifier
:param name: The desired name of the output. If this is
not unique, it will be made to be unique
:param settings: The settings for the output, or *NULL* if
none
:param hotkey_data: Saved hotkey data for the output, or *NULL*
if none
:return: A reference to the newly created output, or
*NULL* if failed
.. function:: void obs_output_addref(obs_output_t *output)
void obs_output_release(obs_output_t *output)
Adds/releases a reference to an output. When the last reference is
released, the output is destroyed.
.. function:: obs_weak_output_t *obs_output_get_weak_output(obs_output_t *output)
obs_output_t *obs_weak_output_get_output(obs_weak_output_t *weak)
These functions are used to get a weak reference from a strong output
reference, or a strong output reference from a weak reference. If
the output is destroyed, *obs_weak_output_get_output* will return
*NULL*.
.. function:: void obs_weak_output_addref(obs_weak_output_t *weak)
void obs_weak_output_release(obs_weak_output_t *weak)
Adds/releases a weak reference to an output.
.. function:: const char *obs_output_get_name(const obs_output_t *output) :return: The name of the output
.. function:: bool obs_output_start(obs_output_t *output)
Starts the output.
:return: *true* if output successfully started, *false* otherwise. If
the output failed to start,
:c:func:`obs_output_get_last_error()` may contain a specific
error string related to the reason
.. function:: void obs_output_stop(obs_output_t *output) Requests the output to stop. The output will wait until all data is sent up until the time the call was made, then when the output has successfully stopped, it will send the "stop" signal. See :ref:`output_signal_handler_reference` for more information on output signals.
.. function:: void obs_output_set_delay(obs_output_t *output, uint32_t delay_sec, uint32_t flags)
Sets the current output delay, in seconds (if the output supports delay)
If delay is currently active, it will set the delay value, but will not
affect the current delay, it will only affect the next time the output is
activated.
:param delay_sec: Amount to delay the output, in seconds
:param flags: | Can be 0 or a combination of one of the following values:
| OBS_OUTPUT_DELAY_PRESERVE - On reconnection, start where it left of on reconnection. Note however that this option will consume extra memory to continually increase delay while waiting to reconnect
.. function:: uint32_t obs_output_get_delay(const obs_output_t *output) Gets the currently set delay value, in seconds.
.. function:: uint32_t obs_output_get_active_delay(const obs_output_t *output) If delay is active, gets the currently active delay value, in seconds. The active delay can increase if the OBS_OUTPUT_DELAY_PRESERVE flag was set when setting a delay.
.. function:: void obs_output_force_stop(obs_output_t *output) Attempts to get the output to stop immediately without waiting for data to send.
.. function:: bool obs_output_active(const obs_output_t *output) :return: *true* if the output is currently active, *false* otherwise
.. function:: obs_data_t *obs_output_defaults(const char *id) :return: An incremented reference to the output's default settings
.. function:: obs_properties_t *obs_output_properties(const obs_output_t *output)
obs_properties_t *obs_get_output_properties(const char *id)
Use these functions to get the properties of an output or output
type. Properties are optionally used (if desired) to automatically
generate user interface widgets to allow users to update settings.
:return: The properties list for a specific existing output. Free
with :c:func:`obs_properties_destroy()`
.. function:: void obs_output_update(obs_output_t *output, obs_data_t *settings) Updates the settings for this output context.
.. function:: bool obs_output_can_pause(const obs_output_t *output) :return: *true* if the output can be paused, *false* otherwise
.. function:: bool obs_output_pause(obs_output_t *output, bool pause)
Pause an output (if supported by the output).
:return: *true* if the output was paused successfully, *false*
otherwise
.. function:: bool obs_output_paused(const obs_output_t *output) :return: *true* if the output is paused, *false* otherwise
.. function:: obs_data_t *obs_output_get_settings(const obs_output_t *output) :return: An incremented reference to the output's settings
.. function:: signal_handler_t *obs_output_get_signal_handler(const obs_output_t *output) :return: The signal handler of the output
.. function:: proc_handler_t *obs_output_get_proc_handler(const obs_output_t *output) :return: The procedure handler of the output
.. function:: void obs_output_set_media(obs_output_t *output, video_t *video, audio_t *audio) Sets the current video/audio handlers for the output (typically :c:func:`obs_get_video()` and :c:func:`obs_get_audio()`). Only used with raw outputs so they can catch the raw video/audio frames.
.. function:: video_t *obs_output_video(const obs_output_t *output)
audio_t *obs_output_audio(const obs_output_t *output)
Gets the current video/audio handlers for the output.
.. function:: void obs_output_set_mixer(obs_output_t *output, size_t mixer_idx)
size_t obs_output_get_mixer(const obs_output_t *output)
Sets/gets the current audio mixer for non-encoded outputs. For
multi-track outputs, this would be the equivalent of setting the mask
only for the specified mixer index.
.. function:: void obs_output_set_mixers(obs_output_t *output, size_t mixers)
size_t obs_output_get_mixers(const obs_output_t *output)
Sets/gets the current audio mixers (via mask) for non-encoded
multi-track outputs. If used with single-track outputs, the
single-track output will use either the first set mixer track in the
bitmask, or the first track if none is set in the bitmask.
.. function:: void obs_output_set_video_encoder(obs_output_t *output, obs_encoder_t *encoder)
void obs_output_set_audio_encoder(obs_output_t *output, obs_encoder_t *encoder, size_t idx)
Sets the video/audio encoders for an encoded output.
:param encoder: The video/audio encoder
:param idx: The audio encoder index if the output supports
multiple audio streams at once
.. function:: obs_encoder_t *obs_output_get_video_encoder(const obs_output_t *output)
obs_encoder_t *obs_output_get_audio_encoder(const obs_output_t *output, size_t idx)
Gets the video/audio encoders for an encoded output.
:param idx: The audio encoder index if the output supports
multiple audio streams at once
:return: The video/audio encoder. The reference is not
incremented
.. function:: void obs_output_set_service(obs_output_t *output, obs_service_t *service)
obs_service_t *obs_output_get_service(const obs_output_t *output)
Sets/gets the service for outputs that require services (such as RTMP
outputs). *obs_output_get_service* does not return an incremented
reference.
.. function:: void obs_output_set_reconnect_settings(obs_output_t *output, int retry_count, int retry_sec);
Sets the auto-reconnect settings for outputs that support it. The
retry time will double on each retry to prevent overloading services.
:param retry_count: Maximum retry count. Set to 0 to disable
reconnecting
:param retry_sec: Starting retry wait duration, in seconds
.. function:: uint64_t obs_output_get_total_bytes(const obs_output_t *output) :return: Total bytes sent/processed
.. function:: int obs_output_get_frames_dropped(const obs_output_t *output) :return: Number of frames that were dropped due to network congestion
.. function:: int obs_output_get_total_frames(const obs_output_t *output) :return: Total frames sent/processed
.. function:: void obs_output_set_preferred_size(obs_output_t *output, uint32_t width, uint32_t height) Sets the preferred scaled resolution for this output. Set width and height to 0 to disable scaling. If this output uses an encoder, it will call obs_encoder_set_scaled_size on the encoder before the stream is started. If the encoder is already active, then this function will trigger a warning and do nothing.
.. function:: uint32_t obs_output_get_width(const obs_output_t *output)
uint32_t obs_output_get_height(const obs_output_t *output)
:return: The width/height of the output
.. function:: float obs_output_get_congestion(obs_output_t *output)
:return: The congestion value. This value is used to visualize the
current congestion of a network output. For example, if
there is no congestion, the value will be 0.0f, if it's
fully congested, the value will be 1.0f
.. function:: int obs_output_get_connect_time_ms(obs_output_t *output)
:return: How long the output took to connect to a server, in
milliseconds
.. function:: bool obs_output_reconnecting(const obs_output_t *output)
:return: *true* if the output is currently reconnecting to a server,
*false* otherwise
.. function:: const char *obs_output_get_supported_video_codecs(const obs_output_t *output)
const char *obs_output_get_supported_audio_codecs(const obs_output_t *output)
:return: Supported video/audio codecs of an encoded output, separated
by semicolen
.. function:: uint32_t obs_output_get_flags(const obs_output_t *output)
uint32_t obs_get_output_flags(const char *id)
:return: The output capability flags
.. function:: void obs_output_set_last_error(obs_output_t *output, const char *message)
const char *obs_output_get_last_error(obs_output_t *output)
Sets/gets the translated error message that is presented to a user in
case of disconnection, inability to connect, etc.
.. function:: void obs_output_set_video_conversion(obs_output_t *output, const struct video_scale_info *conversion) Optionally sets the video conversion information. Only used by raw outputs. Relevant data types used with this function:
enum video_format {
VIDEO_FORMAT_NONE,
/* planar 420 format */
VIDEO_FORMAT_I420, /* three-plane */
VIDEO_FORMAT_NV12, /* two-plane, luma and packed chroma */
/* packed 422 formats */
VIDEO_FORMAT_YVYU,
VIDEO_FORMAT_YUY2, /* YUYV */
VIDEO_FORMAT_UYVY,
/* packed uncompressed formats */
VIDEO_FORMAT_RGBA,
VIDEO_FORMAT_BGRA,
VIDEO_FORMAT_BGRX,
VIDEO_FORMAT_Y800, /* grayscale */
/* planar 4:4:4 */
VIDEO_FORMAT_I444,
};
enum video_colorspace {
VIDEO_CS_DEFAULT,
VIDEO_CS_601,
VIDEO_CS_709,
VIDEO_CS_SRGB,
};
enum video_range_type {
VIDEO_RANGE_DEFAULT,
VIDEO_RANGE_PARTIAL,
VIDEO_RANGE_FULL
};
struct video_scale_info {
enum video_format format;
uint32_t width;
uint32_t height;
enum video_range_type range;
enum video_colorspace colorspace;
};.. function:: void obs_output_set_audio_conversion(obs_output_t *output, const struct audio_convert_info *conversion) Optionally sets the audio conversion information. Only used by raw outputs. Relevant data types used with this function:
enum audio_format {
AUDIO_FORMAT_UNKNOWN,
AUDIO_FORMAT_U8BIT,
AUDIO_FORMAT_16BIT,
AUDIO_FORMAT_32BIT,
AUDIO_FORMAT_FLOAT,
AUDIO_FORMAT_U8BIT_PLANAR,
AUDIO_FORMAT_16BIT_PLANAR,
AUDIO_FORMAT_32BIT_PLANAR,
AUDIO_FORMAT_FLOAT_PLANAR,
};
enum speaker_layout {
SPEAKERS_UNKNOWN,
SPEAKERS_MONO,
SPEAKERS_STEREO,
SPEAKERS_2POINT1,
SPEAKERS_QUAD,
SPEAKERS_4POINT1,
SPEAKERS_5POINT1,
SPEAKERS_5POINT1_SURROUND,
SPEAKERS_7POINT1,
SPEAKERS_7POINT1_SURROUND,
SPEAKERS_SURROUND,
};
struct audio_convert_info {
uint32_t samples_per_sec;
enum audio_format format;
enum speaker_layout speakers;
};.. function:: bool obs_output_can_begin_data_capture(const obs_output_t *output, uint32_t flags)
Determines whether video/audio capture (encoded or raw) is able to
start. Call this before initializing any output data to ensure that
the output can start.
:param flags: Set to 0 to initialize both audio/video, otherwise a
bitwise OR combination of OBS_OUTPUT_VIDEO and/or
OBS_OUTPUT_AUDIO
:return: *true* if data capture can begin
.. function:: bool obs_output_initialize_encoders(obs_output_t *output, uint32_t flags)
Initializes any encoders/services associated with the output. This
must be called for encoded outputs before calling
:c:func:`obs_output_begin_data_capture()`.
:param flags: Set to 0 to initialize both audio/video, otherwise a
bitwise OR combination of OBS_OUTPUT_VIDEO and/or
OBS_OUTPUT_AUDIO
:return: *true* if successful, *false* otherwise
.. function:: bool obs_output_begin_data_capture(obs_output_t *output, uint32_t flags)
Begins data capture from raw media or encoders. This is typically
when the output actually activates (starts) internally. Video/audio
data will start being sent to the callbacks of the output.
:param flags: Set to 0 to initialize both audio/video, otherwise a
bitwise OR combination of OBS_OUTPUT_VIDEO and/or
OBS_OUTPUT_AUDIO
:return: *true* if successful, *false* otherwise. Typically the
return value does not need to be checked if
:c:func:`obs_output_can_begin_data_capture()` was
called
.. function:: void obs_output_end_data_capture(obs_output_t *output) Ends data capture of an output. This is typically when the output actually intentionally deactivates (stops). Video/audio data will stop being sent to the callbacks of the output. The output will trigger the "stop" signal with the OBS_OUTPUT_SUCCESS code to indicate that the output has stopped successfully. See :ref:`output_signal_handler_reference` for more information on output signals.
.. function:: void obs_output_signal_stop(obs_output_t *output, int code)
Ends data capture of an output with an output code, indicating that
the output stopped unexpectedly. This is typically used if for
example the server was disconnected for some reason, or if there was
an error saving to file. The output will trigger the "stop" signal
with the the desired code to indicate that the output has stopped
successfully. See :ref:`output_signal_handler_reference` for more
information on output signals.
:c:func:`obs_output_set_last_error()` may be used in conjunction with
these error codes to optionally relay more detailed error information
to the user
:param code: | Can be one of the following values:
| OBS_OUTPUT_SUCCESS - Successfully stopped
| OBS_OUTPUT_BAD_PATH - The specified path was invalid
| OBS_OUTPUT_CONNECT_FAILED - Failed to connect to a server
| OBS_OUTPUT_INVALID_STREAM - Invalid stream path
| OBS_OUTPUT_ERROR - Generic error
| OBS_OUTPUT_DISCONNECTED - Unexpectedly disconnected
| OBS_OUTPUT_UNSUPPORTED - The settings, video/audio format, or codecs are unsupported by this output
| OBS_OUTPUT_NO_SPACE - Ran out of disk space
.. function:: uint64_t obs_output_get_pause_offset(obs_output_t *output) Returns the current pause offset of the output. Used with raw outputs to calculate system timestamps when using calculated timestamps (see FFmpeg output for an example).