WebGear API Parameters¶

enablePiCamera¶

This parameter provide direct access to PiGear or CamGear APIs respectively in WebGear. This means the if enablePiCamera flag is True, the PiGear API will be accessed, and if False, the CamGear API will be accessed.

Data-Type: Boolean

Default Value: Its default value is False.

Usage:

WebGear(enablePiCamera=True) # enable access to PiGear API

options¶

This parameter can be used to pass user-defined parameter to WebGear API by formatting them as this parameter's attribute.

Data-Type: Dictionary

Default Value: Its default value is {}

WebGear Specific attributes¶

• custom_data_location (string) : Can be used to change/alter default location path to somewhere else. Its usage is as follows:

  # set default location to '/home/foo/foo1'
  options = {"custom_data_location": "/home/foo/foo1"}
  # assign it
  WebGear(logging=True, **options)
  

• custom_video_endpoint (string) : Can be used to change/alter default /video video endpoint path to any alphanumeric string value. Its usage is as follows:

  New in v0.3.1

  custom_video_endpoint attribute was added in v0.3.1.

  Only alphanumeric string with no space in between are allowed as custom_video_endpoint value. Any other value will be discarded.

  WebGear's Default Theme which expects only default /video video endpoint path, will fail to work, if it is customized to any other value using this custom_video_endpoint attribute.

  # custom alphanumeric video endpoint string
  options = {"custom_video_endpoint": "xyz"}
  # initialize WebGear app and assign it
  web = WebGear(logging=True, **options)
  

  Hence, default video endpoint will now be available at /xyz path.

• overwrite_default_files (boolean) : Can be used to force trigger the Auto-generation process to overwrite existing data-files. Its usage is as follows:

  Remember only downloaded files will be overwritten in this process, and any other file/folder will NOT be affected/overwritten.

  # force trigger the Auto-generation process
  options = {"overwrite_default_files": True}
  # assign it
  WebGear(logging=True, **options)
  

• frame_size_reduction (int/float) : This attribute controls the size reduction (in percentage) of the frame to be streamed on Server and it has the most significant effect on performance. The value defaults to 25, and must be no higher than 90 (fastest, max compression, Barely Visible frame-size) and no lower than 0 (slowest, no compression, Original frame-size). Its recommended value is between 40-60. Its usage is as follows:

  # frame-size will be reduced by 50%
  options = {"frame_size_reduction": 50} 
  # assign it
  WebGear(logging=True, **options)
  

• jpeg_compression_quality: (int/float) This attribute controls the JPEG quantization factor. Its value varies from 10 to 100 (the higher is the better quality but performance will be lower). Its default value is 90. Its usage is as follows:

  New in v0.2.2

  jpeg_compression_quality attribute was added in v0.2.2.

  # activate jpeg encoding and set quality 95%
  options = {"jpeg_compression_quality": 95}
  # assign it
  WebGear(logging=True, **options)
  

• jpeg_compression_fastdct: (bool) This attribute if True, WebGear API uses fastest DCT method that speeds up decoding by 4-5% for a minor loss in quality. Its default value is also True, and its usage is as follows:

  New in v0.2.2

  jpeg_compression_fastdct attribute was added in v0.2.2.

  # activate jpeg encoding and enable fast dct
  options = {"jpeg_compression_fastdct": True}
  # assign it
  WebGear(logging=True, **options)
  

• jpeg_compression_fastupsample: (bool) This attribute if True, WebGear API use fastest color upsampling method. Its default value is False, and its usage is as follows:

  New in v0.2.2

  jpeg_compression_fastupsample attribute was added in v0.2.2.

  # activate jpeg encoding and enable fast upsampling
  options = {"jpeg_compression_fastupsample": True}
  # assign it
  WebGear(logging=True, **options)
  

• jpeg_compression_colorspace: (str) This internal attribute is used to specify incoming frames colorspace with compression. Its usage is as follows:

  Supported jpeg_compression_colorspace colorspace values are RGB, BGR, RGBX, BGRX, XBGR, XRGB, GRAY, RGBA, BGRA, ABGR, ARGB, CMYK. More information can be found here ➶

  New in v0.2.2

  jpeg_compression_colorspace attribute was added in v0.2.2.

  # Specify incoming frames are `grayscale`
  options = {"jpeg_compression": "GRAY"}
  # assign it
  WebGear(logging=True, **options)
  

• enable_infinite_frames (boolean) : Can be used to continue streaming (instead of terminating immediately) with emulated blank frames with text "No Input", whenever the input source disconnects. Its default value is False. Its usage is as follows:

  New in v0.2.1

  enable_infinite_frames attribute was added in v0.2.1.

  # emulate infinite frames
  options = {"enable_infinite_frames": True}
  # assign it
  WebGear(logging=True, **options)
  

• skip_generate_webdata (boolean) : Can be used to completely disable Data-Files Auto-Generation WorkFlow in WebGear API, and thereby no default data files will be downloaded or validated during its initialization. Its default value is False. Its usage is as follows:

  New in v0.3.0

  skip_generate_webdata attribute was added in v0.3.0.

  # completely disable Data-Files Auto-Generation WorkFlow
  options = {"skip_generate_webdata": True}
  # assign it
  WebGear(logging=True, **options)
  

Parameters for Stabilizer Backend¶

stabilize¶

This parameter enable access to Stabilizer Class for stabilizing frames, i.e. can be set to True(to enable) or unset to False(to disable).

Data-Type: Boolean

Default Value: Its default value is False.

Usage:

WebGear(stabilize=True) # enable stablization

options¶

This parameter can be used in addition, to pass user-defined parameters supported by Stabilizer Class. These parameters can be formatted as this parameter's attribute.

Supported dictionary attributes for Stabilizer Class are:

• SMOOTHING_RADIUS (integer) : This attribute can be used to alter averaging window size. It basically handles the quality of stabilization at the expense of latency and sudden panning. Larger its value, less will be panning, more will be latency and vice-versa. Its default value is 25. You can easily pass this attribute as follows:

  options = {'SMOOTHING_RADIUS': 30}
  

• BORDER_SIZE (integer) : This attribute enables the feature to extend border size that compensates for stabilized output video frames motions. Its default value is 0(no borders). You can easily pass this attribute as follows:

  options = {'BORDER_SIZE': 10}
  

• CROP_N_ZOOM(boolean): This attribute enables the feature where it crops and zooms frames(to original size) to reduce the black borders from stabilization being too noticeable (similar to the Stabilized, cropped and Auto-Scaled feature available in Adobe AfterEffects). It simply works in conjunction with the BORDER_SIZE attribute, i.e. when this attribute is enabled, BORDER_SIZE will be used for cropping border instead of extending them. Its default value is False. You can easily pass this attribute as follows:

  options = {'BORDER_SIZE': 10, 'CROP_N_ZOOM' : True}
  

• BORDER_TYPE (string) : This attribute can be used to change the extended border style. Valid border types are 'black', 'reflect', 'reflect_101', 'replicate' and 'wrap', learn more about it here. Its default value is 'black'. You can easily pass this attribute as follows:

  Altering BORDER_TYPE attribute is Disabled while CROP_N_ZOOM is enabled.

  options = {'BORDER_TYPE': 'black'}
  

Parameters for CamGear backend¶

source¶

This parameter defines the source for the input stream.

Data-Type: Based on input.

Default Value: Its default value is 0.

Its valid input can be one of the following:

• Index (integer): Valid index of the connected video device, for e.g 0, or 1, or 2 etc. as follows:

  WebGear(source=0)
  

• Filepath (string): Valid path of the video file, for e.g "/home/foo.mp4" as follows:

  WebGear(source='/home/foo.mp4')
  

• Streaming Services URL Address (string): Valid Video URL as input when Stream Mode is enabled(i.e. stream_mode=True)

  CamGear internally implements yt_dlp backend class for pipelining live video-frames and metadata from various streaming services. For example Twitch URL can be used as follows:

  Supported Streaming Websites

  The complete list of all supported Streaming Websites URLs can be found here ➶

  WebGear(source='https://www.twitch.tv/shroud', stream_mode=True)
  

• Network Address (string): Valid (http(s), rtp, rtsp, rtmp, mms, etc.) incoming network stream address such as 'rtsp://192.168.31.163:554/' as input:

  WebGear(source='rtsp://192.168.31.163:554/')
  

• GStreamer Pipeline:

  CamGear API also supports GStreamer Pipeline.

  Requirements for GStreamer Pipelining

  Successful GStreamer Pipelining needs your OpenCV to be built with GStreamer support. Checkout this FAQ for compiling OpenCV with GStreamer support.

  Thereby, You can easily check GStreamer support by running print(cv2.getBuildInformation()) python command and see if output contains something similar as follows:

  Video I/O:
  ...
       GStreamer:                   YES (ver 1.8.3)
  ...
  

  Be sure convert video output into BGR colorspace before pipelining as follows:

  WebGear(source='udpsrc port=5000 ! application/x-rtp,media=video,payload=96,clock-rate=90000,encoding-name=H264, ! rtph264depay ! decodebin ! videoconvert ! video/x-raw, format=BGR ! appsink')
  

stream_mode¶

This parameter controls the Stream Mode, .i.e if enabled(stream_mode=True), the CamGear API will interpret the given source input as YouTube URL address.

Data-Type: Boolean

Default Value: Its default value is False.

Usage:

WebGear(source='https://youtu.be/bvetuLwJIkA', stream_mode=True)

backend¶

This parameter manually selects the backend for OpenCV's VideoCapture class (only if specified).

Data-Type: Integer

Default Value: Its default value is 0

Usage:

Its value can be for e.g. backend = cv2.CAP_DSHOW for selecting Direct Show as backend:

WebGear(source=0, backend = cv2.CAP_DSHOW)

options¶

This parameter provides the ability to alter various Source Tweak Parameters available within OpenCV's VideoCapture API properties.

Data-Type: Dictionary

Default Value: Its default value is {}

Usage:

The desired parameters can be passed to WebGear API by formatting them as this parameter's attributes, as follows:

# formatting parameters as dictionary attributes
options = {"CAP_PROP_FRAME_WIDTH":320, "CAP_PROP_FRAME_HEIGHT":240, "CAP_PROP_FPS":60}
# assigning it
WebGear(source=0, **options)

Parameters for PiGear backend¶

camera_num¶

This parameter selects the camera index to be used as the source, allowing you to drive these multiple cameras simultaneously from within a single Python session. Its value can only be zero or greater, otherwise, WebGear API will throw ValueError for any negative value.

Data-Type: Integer

Default Value: Its default value is 0.

Usage:

# select Camera Module at index `1`
WebGear(enablePiCamera=True, camera_num=1)

resolution¶

This parameter controls the resolution - a tuple (i.e. (width,height)) of two values giving the width and height of the output frames.

Data-Type: Tuple

Default Value: Its default value is (640,480).

Usage:

WebGear(enablePiCamera=True, resolution=(1280,720)) # sets 1280x720 resolution

framerate¶

This parameter controls the framerate of the source.

Data-Type: integer/float

Default Value: Its default value is 30.

Usage:

WebGear(enablePiCamera=True, framerate=60) # sets 60fps framerate

options¶

This dictionary parameter in the internal PiGear API backend allows you to control various camera settings for both the picamera2 and legacy picamera backends and some internal API tasks. These settings include:

A. Configurational Camera Parameters¶

• These parameters are provided by the underlying backend library (depending upon backend in use), and must be applied to the camera system before the camera can be started.
• These parameter include: Brightness, Contrast, Saturation, Exposure, Colour Temperature, Colour Gains, etc.
• All supported parameters are listed in this Usage example ➶

B. User-defined Parameters¶

• These user-defined parameters control specific internal behaviors of the API and perform certain tasks on the camera objects.
• All supported User-defined Parameters are listed here ➶

Data-Type: Dictionary

Default Value: Its default value is {}

Usage:

You can format these user-defined and configurational parameters as attributes of this options dictionary parameter as follows:

# formulate various Picamera2 API parameters
options = {
    "queue": True,
    "buffer_count": 4,
    "controls": {"Brightness": 0.5, "ExposureValue": 2.0},
    "exposure_compensation": 15,
    "sensor": {"output_size": (480, 320)},  # !!! will override `resolution` !!!
}

# open pi video stream with defined parameters
stream = WebGear(enablePiCamera=True, resolution=(640, 480), framerate=60, logging=True, **options).start()

# formulate various Picamera API parameters
options = {
    "hflip": True,
    "exposure_mode": "auto",
    "iso": 800,
    "exposure_compensation": 15,
    "awb_mode": "horizon",
    "sensor_mode": 0,
}

# open pi video stream with defined parameters
stream = WebGear(enablePiCamera=True, resolution=(640, 480), framerate=60, logging=True, **options).start()

Common Parameters¶

colorspace¶

This parameter selects the colorspace of the source stream.

Data-Type: String

Default Value: Its default value is None.

Usage:

WebGear(colorspace="COLOR_BGR2HSV")

logging¶

This parameter enables logging (if True), essential for debugging.

Data-Type: Boolean

Default Value: Its default value is False.

Usage:

WebGear(logging=True)

time_delay¶

This parameter set the time delay (in seconds) before the WebGear API start reading the frames. This delay is only required if the source required some warm-up delay before starting up.

Data-Type: Integer

Default Value: Its default value is 0.

Usage:

WebGear(time_delay=1)  # set 1 seconds time delay