Before using the mxpi_opencvosd plugin, you need to use the OSD-related model files. Execute the operators/opencvosd/generate_osd_om.sh script in the installation directory of Vision SDK to generate the required model files. Multiple mxpi_opencvosd instances can be created for a single pipeline.

Ensure that the ATC-related environment variables of the current user are correctly set and the ATC tool can work properly.
Ensure that the user has the write permission on the ASCEND_OPP_PATH directory. The default path of the ASCEND_OPP_PATH directory is /usr/local/Ascend/cann/opp for the root user and $HOME/Ascend/cann/opp for a common user.

Function	Calls basic OSD functions to draw basic units, such as frames, words, lines, and circles, on images.
Synchronous/Asynchronous (Status)	Synchronous
Constraints	The osd parameter in MxpiOsdInstancesList must follow the restrictions of the OpenCV port. The lengths of MxpiVisionList and MxpiOsdInstancesList in each input buffer must be the same.
Plugin Base Class (Factory)	mxpi_opencvosd
Input/Output	Input: buffer (data type: MxpiBuffer), metadata (data type: MxpiVisionList), and metadata (data type: MxpiOsdInstancesList) Output: buffer (data type: MxpiBuffer), metadata (data type: MxpiVisionList)
Port Format (Caps)	Static dual-input: {"image/yuv"},{"metadata/osd"} Static output: {"image/yuv"}
Property	For details, see Table 1.

**Table 1** mxpi_opencvosd plugin properties
Property Name	Description	Mandatory or Not	Modifiable or Not
dataSourceImage	Buffer index name of input port 0. The default value is the key of the metadata corresponding to the output port 0 of the upstream plugin.	No	Yes
dataSourceOsd	Buffer index name of input port 1. The default value is the key of the metadata corresponding to the output port 1 of the upstream plugin.	No	Yes

Example

Call the basic OSD function buffer (MxpiOsdInstancesList) to draw basic units, such as frames, words, lines, and circles, on the input image (MxpiVisionList) and output the buffer to the downstream plugin.

Click to enlarge

Pipeline sample:

"mxpi_opencvosd0":{
    "props":{
  "dataSourceImage":"mxpi_channelimagesstitcher0_0",
  "dataSourceOsd":"mxpi_channelosdcoordsconverter0"
    },
    "factory":"mxpi_opencvosd",
    "next":"queue10"
},