wehub-resource-sync
96 lines
4.1 KiB
Markdown
96 lines
4.1 KiB
Markdown
# ProposalLayer Plugin [DEPRECATED]
|
|
|
|
**This plugin is deprecated since TensorRT 10.12 and will be removed in a future release. No alternatives are planned to be provided.**
|
|
|
|
**Table Of Contents**
|
|
- [Description](#description)
|
|
* [Structure](#structure)
|
|
- [Parameters](#parameters)
|
|
- [Additional resources](#additional-resources)
|
|
- [License](#license)
|
|
- [Changelog](#changelog)
|
|
- [Known issues](#known-issues)
|
|
|
|
## Description
|
|
|
|
The `ProposalLayer` plugin generates the first-stage detection (ROI candidates) out of the scores, refinement info from RPN (Region Proposal Network) and pre-defined anchors. It is used in `sampleUffMaskRCNN`.
|
|
|
|
### Structure
|
|
|
|
This plugin supports the NCHW format. It takes two input tenosrs: `object_score` and `object_delta`
|
|
|
|
`object_score` is the objectness score from RPN. `object_score`'s shape is `[N, anchors, 2, 1]` where `N` is the batch_size, `anchors` is the total number of anchors and `2` means 2 classes of objectness - foreground and background.
|
|
|
|
`object_delta` is the refinement info from RPN of shape `[N, anchors, 4, 1]`. `4` refers to the 4 elements of refinement information - `[dy, dx, dh, dw]`
|
|
|
|
This plugin generates one output tensor of shape `[N, keep_topk, 4]` where `keep_topk` is the maximum number of detections left after NMS and `4` refers to coordinates of ROI
|
|
candidates `[y1, x1, y2, x2]`
|
|
|
|
The default anchors are generated in this plugin during `initialization` method.
|
|
For ResNet101 with 1024*1024 input image, the number of anchors can be computed as:
|
|
```
|
|
Anchors in feature map P2: 256*256*3
|
|
Anchors in feature map P3: 128*128*3
|
|
Anchors in feature map P4: 64*64*3
|
|
Anchors in feature map P5: 32*32*3
|
|
Anchors in feature map P6(maxpooling): 16*16*3
|
|
|
|
total number of anchors: 87296*3 = 261888
|
|
```
|
|
|
|
## Parameters
|
|
|
|
This plugin has the plugin creator class `ProposalLayerPluginCreator` and the plugin class `ProposalLayer`.
|
|
|
|
The following parameters were used to create `ProposalLayer` instance:
|
|
|
|
| Type | Parameter | Description
|
|
|-------------------|----------------------------------|--------------------------------------------------------
|
|
|`int` |`prenms_topk` |The number of ROIs which will be kept before NMS.
|
|
|`int` |`keep_topk` |Number of detections will be kept after NMS.
|
|
|`float` |`iou_threshold` |IOU threshold value used in NMS.
|
|
|`int[3]` |`image_size` |Input image size in CHW. Only supports C=3 and defaults to [3,1024,1024].
|
|
|
|
## Limitations
|
|
|
|
The number of anchors is capped at 1024 to support embedded devices with smaller shared memory capacity.
|
|
|
|
To enable support for a device with higher memory, calls to `sortPerClass`, `PerClassNMS` and `KeepTopKGather` can be modified in `proposalRefineBatchClassNMS` ([maskRCNNKernels.cu](https://github.com/NVIDIA/TensorRT/blob/main/plugin/common/kernels/maskRCNNKernels.cu)).
|
|
|
|
|
|
## Limitations
|
|
|
|
The attribute `prenms_topk` is capped at 1024 to support embedded devices with smaller shared memory capacity.
|
|
|
|
To enable support for a device with higher memory, calls to `sortPerClass`, `PerClassNMS` and `KeepTopKGather` can be modified in `proposalRefineBatchClassNMS` ([maskRCNNKernels.cu](https://github.com/NVIDIA/TensorRT/blob/main/plugin/common/kernels/maskRCNNKernels.cu)).
|
|
|
|
|
|
## Additional resources
|
|
|
|
The following resources provide a deeper understanding of the `ProposalLayer` plugin:
|
|
|
|
- [MaskRCNN](https://github.com/matterport/Mask_RCNN)
|
|
|
|
|
|
## License
|
|
|
|
For terms and conditions for use, reproduction, and distribution, see the [TensorRT Software License Agreement](https://docs.nvidia.com/deeplearning/sdk/tensorrt-sla/index.html)
|
|
documentation.
|
|
|
|
|
|
## Changelog
|
|
|
|
May 2025
|
|
Add deprecation note.
|
|
|
|
January 2022: The [Limitations](#limitations) section was added to this `README.md` file to document limitations of the plugin related to the maximum number of anchors it can support.
|
|
|
|
July 2020: Add (optional) plugin parameter for specifying image size.
|
|
|
|
June 2019: First release of proposeLayerPlugin.
|
|
|
|
|
|
## Known issues
|
|
|
|
There are no known issues in this plugin.
|