camerabin2

camerabin2

Properties

GstCaps * audio-capture-caps Read / Write
GstCaps * audio-capture-supported-caps Read
GstElement * audio-src Read / Write
GstElement * camera-src Read / Write
gboolean idle Read
GstCaps * image-capture-caps Read / Write
GstElement * image-capture-encoder Read / Write
GstElement * image-capture-muxer Read / Write
GstCaps * image-capture-supported-caps Read
GstElement * image-filter Read / Write
gchar * location Read / Write
gfloat max-zoom Read
GstCameraBin2Mode mode Read / Write
gboolean mute Read / Write
gboolean post-previews Read / Write
GstCaps * preview-caps Read / Write
GstElement * preview-filter Read / Write
GstCaps * video-capture-caps Read / Write
GstCaps * video-capture-supported-caps Read
GstElement * video-filter Read / Write
GstEncodingProfile * video-profile Read / Write
GstCaps * viewfinder-caps Read / Write
GstElement * viewfinder-filter Read / Write
GstElement * viewfinder-sink Read / Write
GstCaps * viewfinder-supported-caps Read
gfloat zoom Read / Write
GstEncodingProfile * image-profile Read / Write
GstElement * audio-source Read / Write
GstElement * camera-source Read / Write
GstElement * audio-filter Read / Write
GstCamFlags flags Read / Write

Signals

Types and Values

struct GstCameraBin2

Object Hierarchy

    GObject
    ╰── GstObject
        ╰── GstElement
            ╰── GstBin
                ╰── GstPipeline
                    ╰── GstCameraBin2

Implemented Interfaces

GstCameraBin2 implements GstChildProxy and GstTagSetter.

Description

CameraBin2 is a high-level camera object that encapsulates gstreamer elements, providing an API for controlling a digital camera.

Note that camerabin2 is still UNSTABLE and under development.

CameraBin2 has the following main features:

  • Record videos
  • Capture pictures
  • Display a viewfinder
  • Post preview images for each capture (video and image)

Usage

Camerabin2 can be created using gst_element_factory_make() just like any other element. Video or image capture mode can be selected using the “mode” property and the file to save the capture is selected using “location” property. After creating camerabin2, applications might want to do some customization (there's a section about this below), then select the desired mode and start capturing. In image capture mode, just send a “start-capture” and a picture will be captured. When the picture is stored on the selected location, a GST_MESSAGE_ELEMENT named 'image-done' will be posted on the GstBus. In video capture mode, send a “start-capture” to start recording, then send a “stop-capture” to stop recording. Note that both signals are asynchronous, so, calling “stop-capture” doesn't guarantee that the video has been properly finished yet. Applications should wait for the 'video-done' message to be posted on the bus. In both modes, if “post-previews” is TRUE, a GstBuffer will be post to the GstBus in a field named 'buffer', in a 'preview-image' message of type GST_MESSAGE_ELEMENT.

Customization

Camerabin2 provides various customization properties, allowing the user to set custom filters, selecting the viewfinder sink and formats to use to encode the captured images/videos. GstEncodingProfiles are used to tell camerabin2 which formats it should encode the captures to, those should be set to “image-profile” and “video-profile”. Default is jpeg for images, and ogg (theora and vorbis) for video. If a profile without an audio stream is set for video, audio will be disabled on recordings. “preview-caps” can be used to select which format preview images should be posted on the GstBus. It has to be a raw video format. Camerabin2 has a “camera-source” property so applications can set their source that will provide buffers for the viewfinder and for captures. This camera source is a special type of source that has 3 pads. To use a 'regular' source with a single pad you should use GstWrapperCameraBinSource, it will adapt your source and provide 3 pads. Applications can also select the desired viewfinder sink using “viewfinder-sink”, it is also possible to select the audio source using “audio-source”. The viewfinder resolution can be configured using “viewfinder-caps”, these GstCaps should be a subset of “viewfinder-supported-caps”. To select the desired resolution for captures, camerabin2 provides “image-capture-caps” and “video-capture-caps”, these caps must be a subset of what the source can produce. The allowed caps can be probed using “image-capture-supported-caps” and “video-capture-supported-caps”. In an analogous way, there are “audio-capture-caps” and “audio-capture-supported-caps”. Camerabin2 also allows applications to insert custom GstElements on any of its branches: video capture, image capture, viewfinder and preview. Check “video-filter”, “image-filter”, “viewfinder-filter” and “preview-filter”.

Example launch line

Unfortunatelly, camerabin2 can't be really used from gst-launch, as you need to send signals to control it. The following pipeline might be able to show the viewfinder using all the default elements.

1
gst-launch -v -m camerabin2

Functions

Types and Values

struct GstCameraBin2

struct GstCameraBin2;

Property Details

The “audio-capture-caps” property

  “audio-capture-caps”       GstCaps *

Format to capture audio for video recording represented as GstCaps.

Flags: Read / Write

The “audio-capture-supported-caps” property

  “audio-capture-supported-caps” GstCaps *

Formats supported for capturing audio represented as GstCaps.

Flags: Read

The “audio-src” property

  “audio-src”                GstElement *

The audio source element to be used on video recordings. It is only taken into use on the next null to ready transition.

Flags: Read / Write

The “camera-src” property

  “camera-src”               GstElement *

The camera source element to be used. It is only taken into use on the next null to ready transition.

Flags: Read / Write

The “idle” property

  “idle”                     gboolean

If camerabin2 is idle (not doing captures).

Flags: Read

Default value: TRUE

The “image-capture-caps” property

  “image-capture-caps”       GstCaps *

Caps for image capture.

Flags: Read / Write

The “image-capture-encoder” property

  “image-capture-encoder”    GstElement *

The image encoder element to be used on image captures.

Flags: Read / Write

The “image-capture-muxer” property

  “image-capture-muxer”      GstElement *

The image encoder element to be used on image captures.

Flags: Read / Write

The “image-capture-supported-caps” property

  “image-capture-supported-caps” GstCaps *

Formats supported for capturing images represented as GstCaps.

Flags: Read

The “image-filter” property

  “image-filter”             GstElement *

The element that will process captured image frames. (Should be set on NULL state).

Flags: Read / Write

The “location” property

  “location”                 gchar *

Location to save the captured files. A %d might be used on thefilename as a placeholder for a numeric index of the capture.Default is cap_%d.

Flags: Read / Write

Default value: "cap_%d"

The “max-zoom” property

  “max-zoom”                 gfloat

Digital zoom factor (e.g. 1.5 means 1.5x).

Flags: Read

Allowed values: >= 1

Default value: 10

The “mode” property

  “mode”                     GstCameraBin2Mode

Set the mode of operation: still image capturing or video recording.

Flags: Read / Write

Default value: Still image capture (default)

The “mute” property

  “mute”                     gboolean

If the audio recording should be muted. Note that this still saves audio data to the resulting file, but they are silent. Use a video-profile without audio to disable audio completely.

Flags: Read / Write

Default value: FALSE

The “post-previews” property

  “post-previews”            gboolean

If capture preview images should be posted to the bus.

Flags: Read / Write

Default value: FALSE

The “preview-caps” property

  “preview-caps”             GstCaps *

The caps of the preview image to be posted.

Flags: Read / Write

The “preview-filter” property

  “preview-filter”           GstElement *

The element that will process preview buffers. (Should be set on NULL state).

Flags: Read / Write

The “video-capture-caps” property

  “video-capture-caps”       GstCaps *

Caps for video capture.

Flags: Read / Write

The “video-capture-supported-caps” property

  “video-capture-supported-caps” GstCaps *

Formats supported for capturing videos represented as GstCaps.

Flags: Read

The “video-filter” property

  “video-filter”             GstElement *

The element that will process captured video frames. (Should be set on NULL state).

Flags: Read / Write

The “video-profile” property

  “video-profile”            GstEncodingProfile *

The GstEncodingProfile to use for video recording. Audio is enabled when this profile supports audio.

Flags: Read / Write

The “viewfinder-caps” property

  “viewfinder-caps”          GstCaps *

Restricts the caps that can be used on the viewfinder.

Flags: Read / Write

The “viewfinder-filter” property

  “viewfinder-filter”        GstElement *

The element that will process frames going to the viewfinder. (Should be set on NULL state).

Flags: Read / Write

The “viewfinder-sink” property

  “viewfinder-sink”          GstElement *

The video sink of the viewfinder. It is only taken into use on the next null to ready transition.

Flags: Read / Write

The “viewfinder-supported-caps” property

  “viewfinder-supported-caps” GstCaps *

The caps that the camera source can produce on the viewfinder pad.

Flags: Read

The “zoom” property

  “zoom”                     gfloat

Digital zoom factor (e.g. 1.5 means 1.5x).

Flags: Read / Write

Allowed values: [1,10]

Default value: 1

The “image-profile” property

  “image-profile”            GstEncodingProfile *

The GstEncodingProfile to use for image captures.

Flags: Read / Write

The “audio-source” property

  “audio-source”             GstElement *

The audio source element to be used on video recordings. It is only taken into use on the next null to ready transition.

Flags: Read / Write

The “camera-source” property

  “camera-source”            GstElement *

The camera source element to be used. It is only taken into use on the next null to ready transition.

Flags: Read / Write

The “audio-filter” property

  “audio-filter”             GstElement *

The element that will process captured audio buffers when recording. (Should be set on NULL state).

Flags: Read / Write

The “flags” property

  “flags”                    GstCamFlags

Flags to control behaviour.

Flags: Read / Write

Signal Details

The “start-capture” signal

void
user_function (GstCameraBin2 *gstcamerabin2,
               gpointer       user_data)

Flags: Action

The “stop-capture” signal

void
user_function (GstCameraBin2 *gstcamerabin2,
               gpointer       user_data)

Flags: Action