- How to use
- How to compile on Linux
- How to compile on Windows
- How to train (Pascal VOC Data)
- How to train (to detect your custom objects)
- When should I stop training
- How to improve object detection
- How to mark bounded boxes of objects and create annotation files
- Using Yolo9000
- How to use Yolo as DLL
https://arxiv.org/abs/1612.08242 |
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https://arxiv.org/abs/1612.08242 |
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A Yolo cross-platform Windows and Linux version (for object detection). Contributtors: https://github.com/pjreddie/darknet/graphs/contributors
This repository is forked from Linux-version: https://github.com/pjreddie/darknet
More details: http://pjreddie.com/darknet/yolo/
This repository supports:
- both Windows and Linux
- both OpenCV 3.x and OpenCV 2.4.13
- both cuDNN 5 and cuDNN 6
- CUDA >= 7.5
- also create SO-library on Linux and DLL-library on Windows
- Linux GCC>=4.9 or Windows MS Visual Studio 2015 (v140): https://go.microsoft.com/fwlink/?LinkId=532606&clcid=0x409 (or offline ISO image)
- CUDA 8.0: https://developer.nvidia.com/cuda-downloads
- OpenCV 3.x: https://sourceforge.net/projects/opencvlibrary/files/opencv-win/3.2.0/opencv-3.2.0-vc14.exe/download
- or OpenCV 2.4.13: https://sourceforge.net/projects/opencvlibrary/files/opencv-win/2.4.13/opencv-2.4.13.2-vc14.exe/download
- OpenCV allows to show image or video detection in the window and store result to file that specified in command line
-out_filename res.avi
- OpenCV allows to show image or video detection in the window and store result to file that specified in command line
- GPU with CC >= 2.0 if you use CUDA, or GPU CC >= 3.0 if you use cuDNN + CUDA: https://en.wikipedia.org/wiki/CUDA#GPUs_supported
Pre-trained models for different cfg-files can be downloaded from (smaller -> faster & lower quality):
yolo.cfg
(194 MB COCO-model) - require 4 GB GPU-RAM: http://pjreddie.com/media/files/yolo.weightsyolo-voc.cfg
(194 MB VOC-model) - require 4 GB GPU-RAM: http://pjreddie.com/media/files/yolo-voc.weightstiny-yolo.cfg
(60 MB COCO-model) - require 1 GB GPU-RAM: http://pjreddie.com/media/files/tiny-yolo.weightstiny-yolo-voc.cfg
(60 MB VOC-model) - require 1 GB GPU-RAM: http://pjreddie.com/media/files/tiny-yolo-voc.weightsyolo9000.cfg
(186 MB Yolo9000-model) - require 4 GB GPU-RAM: http://pjreddie.com/media/files/yolo9000.weights
Put it near compiled: darknet.exe
You can get cfg-files by path: darknet/cfg/
Others: https://www.youtube.com/channel/UC7ev3hNVkx4DzZ3LO19oebg
darknet_voc.cmd
- initialization with 194 MB VOC-model yolo-voc.weights & yolo-voc.cfg and waiting for entering the name of the image filedarknet_demo_voc.cmd
- initialization with 194 MB VOC-model yolo-voc.weights & yolo-voc.cfg and play your video file which you must rename to: test.mp4darknet_demo_store.cmd
- initialization with 194 MB VOC-model yolo-voc.weights & yolo-voc.cfg and play your video file which you must rename to: test.mp4, and store result to: res.avidarknet_net_cam_voc.cmd
- initialization with 194 MB VOC-model, play video from network video-camera mjpeg-stream (also from you phone)darknet_web_cam_voc.cmd
- initialization with 194 MB VOC-model, play video from Web-Camera number #0darknet_coco_9000.cmd
- initialization with 186 MB Yolo9000 COCO-model, and show detection on the image: dog.jpgdarknet_coco_9000_demo.cmd
- initialization with 186 MB Yolo9000 COCO-model, and show detection on the video (if it is present): street4k.mp4, and store result to: res.avi
On Linux use ./darknet
instead of darknet.exe
, like this:./darknet detector test ./cfg/coco.data ./cfg/yolo.cfg ./yolo.weights
- 194 MB COCO-model - image:
darknet.exe detector test data/coco.data yolo.cfg yolo.weights -i 0 -thresh 0.2
- Alternative method 194 MB COCO-model - image:
darknet.exe detect yolo.cfg yolo.weights -i 0 -thresh 0.2
- 194 MB VOC-model - image:
darknet.exe detector test data/voc.data yolo-voc.cfg yolo-voc.weights -i 0
- 194 MB COCO-model - video:
darknet.exe detector demo data/coco.data yolo.cfg yolo.weights test.mp4 -i 0
- 194 MB VOC-model - video:
darknet.exe detector demo data/voc.data yolo-voc.cfg yolo-voc.weights test.mp4 -i 0
- 194 MB COCO-model - save result to the file res.avi:
darknet.exe detector demo data/coco.data yolo.cfg yolo.weights test.mp4 -i 0 -out_filename res.avi
- 194 MB VOC-model - save result to the file res.avi:
darknet.exe detector demo data/voc.data yolo-voc.cfg yolo-voc.weights test.mp4 -i 0 -out_filename res.avi
- Alternative method 194 MB VOC-model - video:
darknet.exe yolo demo yolo-voc.cfg yolo-voc.weights test.mp4 -i 0
- 60 MB VOC-model for video:
darknet.exe detector demo data/voc.data tiny-yolo-voc.cfg tiny-yolo-voc.weights test.mp4 -i 0
- 194 MB COCO-model for net-videocam - Smart WebCam:
darknet.exe detector demo data/coco.data yolo.cfg yolo.weights http://192.168.0.80:8080/video?dummy=param.mjpg -i 0
- 194 MB VOC-model for net-videocam - Smart WebCam:
darknet.exe detector demo data/voc.data yolo-voc.cfg yolo-voc.weights http://192.168.0.80:8080/video?dummy=param.mjpg -i 0
- 194 MB VOC-model - WebCamera #0:
darknet.exe detector demo data/voc.data yolo-voc.cfg yolo-voc.weights -c 0
- 186 MB Yolo9000 - image:
darknet.exe detector test cfg/combine9k.data yolo9000.cfg yolo9000.weights
- 186 MB Yolo9000 - video:
darknet.exe detector demo cfg/combine9k.data yolo9000.cfg yolo9000.weights test.mp4
- Remeber to put data/9k.tree and data/coco9k.map under the same folder of your app if you use the cpp api to build an app
- To process a list of images
image_list.txt
and save results of detection toresult.txt
use:
darknet.exe detector test data/voc.data yolo-voc.cfg yolo-voc.weights < image_list.txt > result.txt
You can comment this line so that each image does not require pressing the button ESC: https://github.com/AlexeyAB/darknet/blob/6ccb41808caf753feea58ca9df79d6367dedc434/src/detector.c#L509
-
Download for Android phone mjpeg-stream soft: IP Webcam / Smart WebCam
- Smart WebCam - preferably: https://play.google.com/store/apps/details?id=com.acontech.android.SmartWebCam2
- IP Webcam: https://play.google.com/store/apps/details?id=com.pas.webcam
-
Connect your Android phone to computer by WiFi (through a WiFi-router) or USB
-
Start Smart WebCam on your phone
-
Replace the address below, on shown in the phone application (Smart WebCam) and launch:
- 194 MB COCO-model:
darknet.exe detector demo data/coco.data yolo.cfg yolo.weights http://192.168.0.80:8080/video?dummy=param.mjpg -i 0
- 194 MB VOC-model:
darknet.exe detector demo data/voc.data yolo-voc.cfg yolo-voc.weights http://192.168.0.80:8080/video?dummy=param.mjpg -i 0
Just do make
in the darknet directory.
Before make, you can set such options in the Makefile
: link
GPU=1
to build with CUDA to accelerate by using GPU (CUDA should be in/usr/local/cuda
)CUDNN=1
to build with cuDNN v5/v6 to accelerate training by using GPU (cuDNN should be in/usr/local/cudnn
)OPENCV=1
to build with OpenCV 3.x/2.4.x - allows to detect on video files and video streams from network cameras or web-camsDEBUG=1
to bould debug version of YoloOPENMP=1
to build with OpenMP support to accelerate Yolo by using multi-core CPULIBSO=1
to build a librarydarknet.so
and binary runable fileuselib
that uses this library. Or you can try to run soLD_LIBRARY_PATH=./:$LD_LIBRARY_PATH ./uselib test.mp4
How to use this SO-library from your own code - you can look at C++ example: https://github.com/AlexeyAB/darknet/blob/master/src/yolo_console_dll.cpp
-
If you have MSVS 2015, CUDA 8.0 and OpenCV 3.0 (with paths:
C:\opencv_3.0\opencv\build\include
&C:\opencv_3.0\opencv\build\x64\vc14\lib
), then start MSVS, openbuild\darknet\darknet.sln
, set x64 and Release, and do the: Build -> Build darknet1.1. Find files
opencv_world320.dll
andopencv_ffmpeg320_64.dll
inC:\opencv_3.0\opencv\build\x64\vc14\bin
and put it near withdarknet.exe
-
If you have other version of CUDA (not 8.0) then open
build\darknet\darknet.vcxproj
by using Notepad, find 2 places with "CUDA 8.0" and change it to your CUDA-version, then do step 1 -
If you don't have GPU, but have MSVS 2015 and OpenCV 3.0 (with paths:
C:\opencv_3.0\opencv\build\include
&C:\opencv_3.0\opencv\build\x64\vc14\lib
), then start MSVS, openbuild\darknet\darknet_no_gpu.sln
, set x64 and Release, and do the: Build -> Build darknet_no_gpu -
If you have OpenCV 2.4.13 instead of 3.0 then you should change pathes after
\darknet.sln
is opened4.1 (right click on project) -> properties -> C/C++ -> General -> Additional Include Directories:
C:\opencv_2.4.13\opencv\build\include
4.2 (right click on project) -> properties -> Linker -> General -> Additional Library Directories:
C:\opencv_2.4.13\opencv\build\x64\vc14\lib
-
If you want to build with CUDNN to speed up then:
-
download and install cuDNN 6.0 for CUDA 8.0: https://developer.nvidia.com/cudnn
-
add Windows system variable
cudnn
with path to CUDNN: https://hsto.org/files/a49/3dc/fc4/a493dcfc4bd34a1295fd15e0e2e01f26.jpg -
open
\darknet.sln
-> (right click on project) -> properties -> C/C++ -> Preprocessor -> Preprocessor Definitions, and add at the beginning of line:CUDNN;
-
Also, you can to create your own darknet.sln
& darknet.vcxproj
, this example for CUDA 8.0 and OpenCV 3.0
Then add to your created project:
- (right click on project) -> properties -> C/C++ -> General -> Additional Include Directories, put here:
C:\opencv_3.0\opencv\build\include;..\..\3rdparty\include;%(AdditionalIncludeDirectories);$(CudaToolkitIncludeDir);$(cudnn)\include
- (right click on project) -> Build dependecies -> Build Customizations -> set check on CUDA 8.0 or what version you have - for example as here: http://devblogs.nvidia.com/parallelforall/wp-content/uploads/2015/01/VS2013-R-5.jpg
- add to project all .c & .cu files from
\src
- (right click on project) -> properties -> Linker -> General -> Additional Library Directories, put here:
C:\opencv_3.0\opencv\build\x64\vc14\lib;$(CUDA_PATH)lib\$(PlatformName);$(cudnn)\lib\x64;%(AdditionalLibraryDirectories)
- (right click on project) -> properties -> Linker -> Input -> Additional dependecies, put here:
..\..\3rdparty\lib\x64\pthreadVC2.lib;cublas.lib;curand.lib;cudart.lib;cudnn.lib;%(AdditionalDependencies)
- (right click on project) -> properties -> C/C++ -> Preprocessor -> Preprocessor Definitions
OPENCV;_TIMESPEC_DEFINED;_CRT_SECURE_NO_WARNINGS;_CRT_RAND_S;WIN32;NDEBUG;_CONSOLE;_LIB;%(PreprocessorDefinitions)
-
compile to .exe (X64 & Release) and put .dll-s near with .exe:
-
pthreadVC2.dll, pthreadGC2.dll
from \3rdparty\dll\x64 -
cusolver64_80.dll, curand64_80.dll, cudart64_80.dll, cublas64_80.dll
- 80 for CUDA 8.0 or your version, from C:\Program Files\NVIDIA GPU Computing Toolkit\CUDA\v8.0\bin -
For OpenCV 3.X:
opencv_world320.dll
andopencv_ffmpeg320_64.dll
fromC:\opencv_3.0\opencv\build\x64\vc14\bin
-
For OpenCV 2.4.13:
opencv_core2413.dll
,opencv_highgui2413.dll
andopencv_ffmpeg2413_64.dll
fromC:\opencv_2.4.13\opencv\build\x64\vc14\bin
-
-
Download pre-trained weights for the convolutional layers (76 MB): http://pjreddie.com/media/files/darknet19_448.conv.23 and put to the directory
build\darknet\x64
-
Download The Pascal VOC Data and unpack it to directory
build\darknet\x64\data\voc
will be created dirbuild\darknet\x64\data\voc\VOCdevkit\
:- http://pjreddie.com/media/files/VOCtrainval_11-May-2012.tar
- http://pjreddie.com/media/files/VOCtrainval_06-Nov-2007.tar
- http://pjreddie.com/media/files/VOCtest_06-Nov-2007.tar
2.1 Download file
voc_label.py
to dirbuild\darknet\x64\data\voc
: http://pjreddie.com/media/files/voc_label.py -
Download and install Python for Windows: https://www.python.org/ftp/python/3.5.2/python-3.5.2-amd64.exe
-
Run command:
python build\darknet\x64\data\voc\voc_label.py
(to generate files: 2007_test.txt, 2007_train.txt, 2007_val.txt, 2012_train.txt, 2012_val.txt) -
Run command:
type 2007_train.txt 2007_val.txt 2012_*.txt > train.txt
-
Set
batch=64
andsubdivisions=8
in the fileyolo-voc.2.0.cfg
: link -
Start training by using
train_voc.cmd
or by using the command line:darknet.exe detector train data/voc.data yolo-voc.2.0.cfg darknet19_448.conv.23
(Note: If you are using CPU, trydarknet_no_gpu.exe
instead ofdarknet.exe
.)
If required change pathes in the file build\darknet\x64\data\voc.data
More information about training by the link: http://pjreddie.com/darknet/yolo/#train-voc
-
Train it first on 1 GPU for like 1000 iterations:
darknet.exe detector train data/voc.data yolo-voc.2.0.cfg darknet19_448.conv.23
-
Then stop and by using partially-trained model
/backup/yolo-voc_1000.weights
run training with multigpu (up to 4 GPUs):darknet.exe detector train data/voc.data yolo-voc.2.0.cfg /backup/yolo-voc_1000.weights -gpus 0,1,2,3
https://groups.google.com/d/msg/darknet/NbJqonJBTSY/Te5PfIpuCAAJ
- Create file
yolo-obj.cfg
with the same content as inyolo-voc.2.0.cfg
(or copyyolo-voc.2.0.cfg
toyolo-obj.cfg)
and:
- change line batch to
batch=64
- change line subdivisions to
subdivisions=8
- change line
classes=20
to your number of objects - change line #237 from
filters=125
to: filters=(classes + 5)x5, so ifclasses=2
then should befilters=35
. Or if you useclasses=1
then writefilters=30
, do not write in the cfg-file: filters=(classes + 5)x5.
(Generally filters
depends on the classes
, num
and coords
, i.e. equal to (classes + coords + 1)*num
, where num
is number of anchors)
So for example, for 2 objects, your file yolo-obj.cfg
should differ from yolo-voc.2.0.cfg
in such lines:
[convolutional]
filters=35
[region]
classes=2
-
Create file
obj.names
in the directorybuild\darknet\x64\data\
, with objects names - each in new line -
Create file
obj.data
in the directorybuild\darknet\x64\data\
, containing (where classes = number of objects):
classes= 2
train = data/train.txt
valid = data/test.txt
names = data/obj.names
backup = backup/
-
Put image-files (.jpg) of your objects in the directory
build\darknet\x64\data\obj\
-
Create
.txt
-file for each.jpg
-image-file - in the same directory and with the same name, but with.txt
-extension, and put to file: object number and object coordinates on this image, for each object in new line:<object-class> <x> <y> <width> <height>
Where:
<object-class>
- integer number of object from0
to(classes-1)
<x> <y> <width> <height>
- float values relative to width and height of image, it can be equal from 0.0 to 1.0- for example:
<x> = <absolute_x> / <image_width>
or<height> = <absolute_height> / <image_height>
- atention:
<x> <y>
- are center of rectangle (are not top-left corner)
For example for img1.jpg
you should create img1.txt
containing:
1 0.716797 0.395833 0.216406 0.147222
0 0.687109 0.379167 0.255469 0.158333
1 0.420312 0.395833 0.140625 0.166667
- Create file
train.txt
in directorybuild\darknet\x64\data\
, with filenames of your images, each filename in new line, with path relative todarknet.exe
, for example containing:
data/obj/img1.jpg
data/obj/img2.jpg
data/obj/img3.jpg
-
Download pre-trained weights for the convolutional layers (76 MB): http://pjreddie.com/media/files/darknet19_448.conv.23 and put to the directory
build\darknet\x64
-
Start training by using the command line:
darknet.exe detector train data/obj.data yolo-obj.cfg darknet19_448.conv.23
(file
yolo-obj_xxx.weights
will be saved to thebuild\darknet\x64\backup\
for each 100 iterations) -
After training is complete - get result
yolo-obj_final.weights
from pathbuild\darknet\x64\backup\
-
After each 1000 iterations you can stop and later start training from this point. For example, after 2000 iterations you can stop training, and later just copy
yolo-obj_2000.weights
frombuild\darknet\x64\backup\
tobuild\darknet\x64\
and start training using:darknet.exe detector train data/obj.data yolo-obj.cfg yolo-obj_2000.weights
-
Also you can get result earlier than all 45000 iterations.
Usually sufficient 2000 iterations for each class(object). But for a more precise definition when you should stop training, use the following manual:
- During training, you will see varying indicators of error, and you should stop when no longer decreases 0.060730 avg:
Region Avg IOU: 0.798363, Class: 0.893232, Obj: 0.700808, No Obj: 0.004567, Avg Recall: 1.000000, count: 8 Region Avg IOU: 0.800677, Class: 0.892181, Obj: 0.701590, No Obj: 0.004574, Avg Recall: 1.000000, count: 8
9002: 0.211667, 0.060730 avg, 0.001000 rate, 3.868000 seconds, 576128 images Loaded: 0.000000 seconds
- 9002 - iteration number (number of batch)
- 0.060730 avg - average loss (error) - the lower, the better
When you see that average loss 0.xxxxxx avg no longer decreases at many iterations then you should stop training.
- Once training is stopped, you should take some of last
.weights
-files fromdarknet\build\darknet\x64\backup
and choose the best of them:
For example, you stopped training after 9000 iterations, but the best result can give one of previous weights (7000, 8000, 9000). It can happen due to overfitting. Overfitting - is case when you can detect objects on images from training-dataset, but can't detect ojbects on any others images. You should get weights from Early Stopping Point:
To get weights from Early Stopping Point:
2.1. At first, in your file obj.data
you must specify the path to the validation dataset valid = valid.txt
(format of valid.txt
as in train.txt
), and if you haven't validation images, just copy data\train.txt
to data\valid.txt
.
2.2 If training is stopped after 9000 iterations, to validate some of previous weights use this commands:
darknet.exe detector recall data/obj.data yolo-obj.cfg backup\yolo-obj_7000.weights
darknet.exe detector recall data/obj.data yolo-obj.cfg backup\yolo-obj_8000.weights
darknet.exe detector recall data/obj.data yolo-obj.cfg backup\yolo-obj_9000.weights
And comapre last output lines for each weights (7000, 8000, 9000):
7586 7612 7689 RPs/Img: 68.23 IOU: 77.86% Recall:99.00%
- IOU - the bigger, the better (says about accuracy) - better to use
- Recall - the bigger, the better (says about accuracy) - actually Yolo calculates true positives, so it shouldn't be used
For example, bigger IOU gives weights yolo-obj_8000.weights
- then use this weights for detection.
How to calculate mAP voc_eval.py or datascience.stackexchange link
Example of custom object detection: darknet.exe detector test data/obj.data yolo-obj.cfg yolo-obj_8000.weights
- Before training:
-
set flag
random=1
in your.cfg
-file - it will increase precision by training Yolo for different resolutions: [link]https://github.com/AlexeyAB/darknet/blob/master/cfg/yolo-voc.2.0.cfg#L244) -
desirable that your training dataset include images with objects at diffrent: scales, rotations, lightings, from different sides
-
for training on small objects, add the parameter
small_object=1
in the last layer [region] in your cfg-file
- After training - for detection:
-
Increase network-resolution by set in your
.cfg
-file (height=608
andwidth=608
) or (height=832
andwidth=832
) or (any value multiple of 32) - this increases the precision and makes it possible to detect small objects: link- you do not need to train the network again, just use
.weights
-file already trained for 416x416 resolution - if error
Out of memory
occurs then in.cfg
-file you should increasesubdivisions=16
, 32 or 64: link
- you do not need to train the network again, just use
Here you can find repository with GUI-software for marking bounded boxes of objects and generating annotation files for Yolo v2: https://github.com/AlexeyAB/Yolo_mark
With example of: train.txt
, obj.names
, obj.data
, yolo-obj.cfg
, air
1-6.txt
, bird
1-4.txt
for 2 classes of objects (air, bird) and train_obj.cmd
with example how to train this image-set with Yolo v2
Simultaneous detection and classification of 9000 objects:
-
yolo9000.weights
- (186 MB Yolo9000 Model) requires 4 GB GPU-RAM: http://pjreddie.com/media/files/yolo9000.weights -
yolo9000.cfg
- cfg-file of the Yolo9000, also there are paths to the9k.tree
andcoco9k.map
https://github.com/AlexeyAB/darknet/blob/617cf313ccb1fe005db3f7d88dec04a04bd97cc2/cfg/yolo9000.cfg#L217-L218-
9k.tree
- WordTree of 9418 categories -<label> <parent_it>
, ifparent_id == -1
then this label hasn't parent: https://raw.githubusercontent.com/AlexeyAB/darknet/master/build/darknet/x64/data/9k.tree -
coco9k.map
- map 80 categories from MSCOCO to WordTree9k.tree
: https://raw.githubusercontent.com/AlexeyAB/darknet/master/build/darknet/x64/data/coco9k.map
-
-
combine9k.data
- data file, there are paths to:9k.labels
,9k.names
,inet9k.map
, (change path to yourcombine9k.train.list
): https://raw.githubusercontent.com/AlexeyAB/darknet/master/build/darknet/x64/data/combine9k.data-
9k.labels
- 9418 labels of objects: https://raw.githubusercontent.com/AlexeyAB/darknet/master/build/darknet/x64/data/9k.labels -
9k.names
- 9418 names of objects: https://raw.githubusercontent.com/AlexeyAB/darknet/master/build/darknet/x64/data/9k.names -
inet9k.map
- map 200 categories from ImageNet to WordTree9k.tree
: https://raw.githubusercontent.com/AlexeyAB/darknet/master/build/darknet/x64/data/inet9k.map
-
-
To compile Yolo as C++ DLL-file
yolo_cpp_dll.dll
- open in MSVS2015 filebuild\darknet\yolo_cpp_dll.sln
, set x64 and Release, and do the: Build -> Build yolo_cpp_dll- You should have installed CUDA 8.0
- To use cuDNN do: (right click on project) -> properties -> C/C++ -> Preprocessor -> Preprocessor Definitions, and add at the beginning of line:
CUDNN;
-
To use Yolo as DLL-file in your C++ console application - open in MSVS2015 file
build\darknet\yolo_console_dll.sln
, set x64 and Release, and do the: Build -> Build yolo_console_dll- you can run your console application from Windows Explorer
build\darknet\x64\yolo_console_dll.exe
- or you can run from MSVS2015 (before this - you should copy 2 files
yolo-voc.cfg
andyolo-voc.weights
to the directorybuild\darknet\
) - after launching your console application and entering the image file name - you will see info for each object:
<obj_id> <left_x> <top_y> <width> <height> <probability>
- to use simple OpenCV-GUI you should uncomment line
//#define OPENCV
inyolo_console_dll.cpp
-file: link - you can see source code of simple example for detection on the video file: link
- you can run your console application from Windows Explorer
yolo_cpp_dll.dll
-API: link
class Detector {
public:
Detector(std::string cfg_filename, std::string weight_filename, int gpu_id = 0);
~Detector();
std::vector<bbox_t> detect(std::string image_filename, float thresh = 0.2, bool use_mean = false);
std::vector<bbox_t> detect(image_t img, float thresh = 0.2, bool use_mean = false);
static image_t load_image(std::string image_filename);
static void free_image(image_t m);
#ifdef OPENCV
std::vector<bbox_t> detect(cv::Mat mat, float thresh = 0.2, bool use_mean = false);
#endif
};