Vision Reference
kevinbotlib.vision
kevinbotlib.vision.SingleFrameSendable
Bases: BinarySendable
Sendable for a single frame of video or an image
encoding
instance-attribute
Frame encoding format
Supported encodings: * JPG * PNG
data_id = 'kevinbotlib.vision.dtype.frame'
class-attribute
instance-attribute
Internally used to differentiate sendable types
struct = {'dashboard': [{'element': 'value', 'format': 'limit:1024'}, {'element': 'resolution', 'format': 'raw'}, {'element': 'quality', 'format': 'raw'}, {'element': 'encoding', 'format': 'raw'}]}
class-attribute
Data structure suggestion for use in dashboard applications
get_dict()
Return the sendable in dictionary form
Returns:
| Name | Type | Description |
|---|---|---|
dict |
dict
|
The sendable data |
kevinbotlib.vision.MjpegStreamSendable
Bases: SingleFrameSendable
Sendable for a single frame of an MJPG stream
Contains all required information for decoding a video stream
data_id = 'kevinbotlib.vision.dtype.mjpeg'
class-attribute
instance-attribute
Internally used to differentiate sendable types
quality
instance-attribute
The current JPEG compression level out of 100 - lower means more compression
resolution
instance-attribute
A two integer list containing the video resolution (WIDTH x HEIGHT)
encoding = 'JPG'
class-attribute
instance-attribute
Frame encoding format
struct = {'dashboard': [{'element': 'value', 'format': 'limit:1024'}, {'element': 'resolution', 'format': 'raw'}, {'element': 'quality', 'format': 'raw'}, {'element': 'encoding', 'format': 'raw'}]}
class-attribute
Data structure suggestion for use in dashboard applications
get_dict()
Return the sendable in dictionary form
Returns:
| Name | Type | Description |
|---|---|---|
dict |
dict
|
The sendable data |
kevinbotlib.vision.FrameEncoders
Encoders from OpenCV Mats into raw bytes or network sendables
encode_sendable_jpg(frame, quality=80)
staticmethod
Encode an OpenCV Mat to a SingleFrameSendable using JPEG encoding
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
frame
|
MatLike
|
The Mat to encode |
required |
quality
|
int
|
The JPEG quality level. Defaults to 80. |
80
|
Returns:
| Name | Type | Description |
|---|---|---|
SingleFrameSendable |
SingleFrameSendable
|
A sendable to be sent over the network |
encode_sendable_png(frame, compression=3)
staticmethod
Encode an OpenCV Mat to a SingleFrameSendable using PNG encoding
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
frame
|
MatLike
|
The Mat to encode |
required |
compression
|
int
|
The PNG compression level. Defaults to 3. |
3
|
Returns:
| Name | Type | Description |
|---|---|---|
SingleFrameSendable |
SingleFrameSendable
|
A sendable to be sent over the network |
encode_jpg(frame, quality=80)
staticmethod
Encode an OpenCV Mat to raw bytes using JPEG encoding
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
frame
|
MatLike
|
The Mat to encode |
required |
quality
|
int
|
The JPEG quality level. Defaults to 80. |
80
|
Returns:
| Name | Type | Description |
|---|---|---|
bytes |
bytes
|
Raw data |
encode_png(frame, compression=3)
staticmethod
Encode an OpenCV Mat to raw bytes using PNG encoding
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
frame
|
MatLike
|
The Mat to encode |
required |
compression
|
int
|
The PNG compression level. Defaults to 3. |
3
|
Returns:
| Name | Type | Description |
|---|---|---|
bytes |
bytes
|
Raw data |
kevinbotlib.vision.FrameDecoders
Decoders from Base64 or network sendables to OpenCV Mats
decode_sendable(sendable)
staticmethod
Decode a SingleFrameSendable into an OpenCV Mat
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
sendable
|
SingleFrameSendable
|
The sendable to decode |
required |
Raises:
| Type | Description |
|---|---|
ValueError
|
If the encoding type isn't recognized |
Returns:
| Name | Type | Description |
|---|---|---|
MatLike |
MatLike
|
An OpenCV Mat |
decode_base64(data, encoding)
staticmethod
Decode a base64 string into an OpenCV Mat
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
data
|
str
|
The base64 data to decode |
required |
encoding
|
str
|
The encoding format. Can be JPG or "PNG" |
required |
Raises:
| Type | Description |
|---|---|
ValueError
|
If the encoding type isn't recognized |
Returns:
| Name | Type | Description |
|---|---|---|
MatLike |
MatLike
|
An OpenCV Mat |
kevinbotlib.vision.VisionCommUtils
Various utilities to integrate vision data with networking
init_comms_types(client)
staticmethod
Allows the use of frame data over the communication client
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
client
|
AbstractSetGetNetworkClient | AbstractPubSubNetworkClient
|
The communication client to integrate with |
required |
kevinbotlib.vision.BaseCamera
Bases: ABC
Abstract class for creating Vision Cameras
get_frame()
abstractmethod
Get the current frame from the camera. Method is blocking until a frame is available.
Returns:
| Type | Description |
|---|---|
tuple[bool, MatLike]
|
tuple[bool, MatLike]: Frame retrieval success and an OpenCV Mat |
set_resolution(width, height)
abstractmethod
Attempt to set the current camera resolution
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
width
|
int
|
Frame width in px |
required |
height
|
int
|
Frame height in px |
required |
kevinbotlib.vision.CameraByIndex
Bases: BaseCamera
Create an OpenCV camera from a device index
Not recommended if you have more than one camera on a system
capture = cv2.VideoCapture(index)
instance-attribute
__init__(index)
Initialize the camera
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
index
|
int
|
Index of the camera |
required |
get_frame()
Get the current frame from the camera. Method is blocking until a frame is available.
Returns:
| Type | Description |
|---|---|
tuple[bool, MatLike]
|
tuple[bool, MatLike]: Frame retrieval success and an OpenCV Mat |
set_resolution(width, height)
Attempt to set the current camera resolution
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
width
|
int
|
Frame width in px |
required |
height
|
int
|
Frame height in px |
required |
kevinbotlib.vision.CameraByDevicePath
Bases: BaseCamera
Create an OpenCV camera from a device path
capture = cv2.VideoCapture(path)
instance-attribute
__init__(path)
Initialize the camera
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
path
|
str
|
Device path of the camera ex: |
required |
get_frame()
Get the current frame from the camera. Method is blocking until a frame is available.
Returns:
| Type | Description |
|---|---|
tuple[bool, MatLike]
|
tuple[bool, MatLike]: Frame retrieval success and an OpenCV Mat |
set_resolution(width, height)
Attempt to set the current camera resolution
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
width
|
int
|
Frame width in px |
required |
height
|
int
|
Frame height in px |
required |
kevinbotlib.vision.VisionPipeline
Bases: ABC
An abstract vision processing pipeline
source = source
instance-attribute
__init__(source)
Pipeline initialization
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
source
|
Callable[[], tuple[bool, MatLike]]
|
Getter for the frame to process |
required |
run(*args, **kwargs)
abstractmethod
Runs the vision pipeline
Returns:
| Type | Description |
|---|---|
tuple[bool, MatLike | None]
|
tuple[bool, MatLike | None]: An OpenCV Mat for pipeline visualization purposes. Can be ignored depending on the use case. |
return_values()
Retrieves the calculations from the latest pipeline iteration
Returns:
| Name | Type | Description |
|---|---|---|
Any |
Any
|
Pipeline calculations |
kevinbotlib.vision.EmptyPipeline
Bases: VisionPipeline
A fake vision pipeline returning the original frame
run()
Fake pipeline. Return the inputs.
Returns: Source values