LibreYOLOXs

LibreYOLOXs Qualcomm-Optimized Model Artifacts

This directory is the shared artifact location for the notebooks in ../notebooks/. The repository tracks the documentation and ignore rules here; model binaries are downloaded or generated locally when you run the workflows.

The same source model is used for three deployment paths:

• QAIRT local conversion and quantization
• SNPE local conversion and quantization
• QAI Hub cloud compilation, quantization, and profiling

---

Model overview

Property	Value
Architecture	YOLOX-Small (LibreYOLOXs)
Framework	LibreYOLO
Task	Object detection
Base checkpoint	LibreYOLO/LibreYOLOXs
Input tensor	images
Input shape	1 x 3 x 640 x 640
Input format	BGR float32, NCHW, values in 0-255

---

Artifact flow

LibreYOLOXs.pt
    |
    `---> LibreYOLOXs.onnx
             |\
             | `---> qairt/LibreYOLOXs_fp32.dlc
             |        `---> qairt/LibreYOLOXs_int8.dlc
             |
             | `---> snpe/LibreYOLOXs_fp32.dlc
             |        `---> snpe/LibreYOLOXs_int8.dlc
             |
             `---> qaihub/LibreYOLOXs_fp32.dlc
                      `---> qaihub/LibreYOLOXs_int8.dlc

All three notebooks reuse the same exported ONNX model.

---

Expected files

Path	Produced by	Description
LibreYOLOXs.pt	All notebooks	Base PyTorch checkpoint, downloaded on demand
LibreYOLOXs.onnx	All notebooks	Shared ONNX export used by all backend flows
qairt/LibreYOLOXs_fp32.dlc	QAIRT notebook	FP32 DLC produced by qairt-converter
qairt/LibreYOLOXs_int8.dlc	QAIRT notebook	INT8 DLC produced by qairt-quantizer
qairt/binary/LibreYOLOXsInference.cpp	QAIRT notebook	C++ inference wrapper source
qairt/binary/LibreYOLOXsInference.h	QAIRT notebook	C++ inference wrapper header
qairt/binary/LibreYOLOXs_int8.bin	QAIRT notebook	Serialised INT8 model for the binary interface
qairt/binary/libLibreYOLOXs.so	QAIRT notebook	Compiled shared library
snpe/LibreYOLOXs_fp32.dlc	SNPE notebook	FP32 DLC produced by snpe-onnx-to-dlc
snpe/LibreYOLOXs_int8.dlc	SNPE notebook	INT8 DLC produced by snpe-dlc-quantize
qaihub/LibreYOLOXs_fp32.dlc	QAI Hub notebook	FP32 DLC downloaded from a cloud compile job
qaihub/LibreYOLOXs_int8.dlc	QAI Hub notebook	INT8 DLC downloaded from cloud quantize + compile jobs
qaihub/binary/LibreYOLOXsInference.cpp	QAI Hub notebook	C++ inference wrapper source
qaihub/binary/LibreYOLOXsInference.h	QAI Hub notebook	C++ inference wrapper header
qaihub/binary/LibreYOLOXs_int8.bin	QAI Hub notebook	Serialised INT8 model for the binary interface

---

Tensor contract

Input

Property	Value
Name	images
Shape	1 x 3 x 640 x 640
Layout	NCHW
Data type	float32
Color order	BGR

Preprocessing used by the notebooks:

1. Letterbox-resize to 640 x 640.
2. Pad with value 114.
3. Keep BGR channel order.
4. Keep values in the 0-255 range.
5. Transpose from HWC to CHW before serialization / inference input assembly.

Outputs

The exported ONNX model is validated in each notebook before backend-specific compilation. The documentation in this directory assumes the shared decoded output layout used by the notebooks:

Output	Shape	Description
bboxes	1 x 8400 x 4	Bounding-box coordinates
scores	1 x 8400 x 81	Objectness plus 80 COCO class scores

---

Calibration data

INT8 flows use representative data prepared by the notebooks from COCO 2017 validation images:

• source images are staged under docker/notebooks/dataset/
• calibration tensors are written to docker/notebooks/subset/calib/
• validation tensors and metadata are written to docker/notebooks/subset/val/
• manifests are written to subset/calib/filenames.txt and subset/val/filenames.txt

The local QAIRT and SNPE quantizers read those manifests directly. The QAI Hub notebook loads the same .raw tensors into NumPy arrays and submits them to the cloud quantization job.

---

Downloading published artifacts

Published files are hosted on Hugging Face:

• fabricionarcizo/LibreYOLOXs

Example download:

huggingface-cli download fabricionarcizo/LibreYOLOXs \
    --local-dir docker/models \
    --exclude "*.gitattributes" "README.md"

You can also generate the same artifact layout locally by running the notebooks in ../notebooks/.

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Binary inference wrappers

The qairt/binary/ and qaihub/binary/ subdirectories contain a C++ inference wrapper generated alongside each INT8 DLC. These files are created locally when you run the respective notebook and are not Git-tracked.

qairt/binary/

File	Description
LibreYOLOXsInference.cpp	C++ inference wrapper source
LibreYOLOXsInference.h	C++ inference wrapper header
LibreYOLOXs_int8.bin	Serialised INT8 model for the binary interface
libLibreYOLOXs.so	Compiled shared library

qaihub/binary/

File	Description
LibreYOLOXsInference.cpp	C++ inference wrapper source
LibreYOLOXsInference.h	C++ inference wrapper header
LibreYOLOXs_int8.bin	Serialised INT8 model for the binary interface

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Related documentation

• ../README.md - Docker environment and setup
• ../notebooks/README.md - notebook workflows and generated data layout