darknet_scripts - YOLO/YOLOv2

Auxilary scripts for working with darknet deep learning famework (2017)
1. How to compute/reproduce YOLOv2 anchors for yolo-voc.cfg? 2. How to visualize genereted anchors? 3. Is gen_anchors.py same as YOLOv2 anchor computation? 4. How to get anchors if My input for network is bigger than 416? 5. How to plot YOLO loss 6. YOLO and Anchors tutorial

How to compute/reproduce YOLOv2 anchors for yolo-voc.cfg?

1. Download The Pascal VOC Data and unpack it to directory

   build\darknet\x64\data\voc

   will be created dir

   build\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

   1.1 Download file

   voc_label.py

   to dir

   build\darknet\x64\data\voc

   : http://pjreddie.com/media/files/voc_label.py

2. Download and install Python for Windows: https://www.python.org/ftp/python/2.7.9/python-2.7.9rc1.amd64.msi

3. Run command:

   python build\darknet\x64\data\voc\voc_label.py

   (to generate files: 2007test.txt, 2007train.txt, 2007val.txt, 2012train.txt, 2012_val.txt)

4. Run command:

   type 2007_train.txt 2007_val.txt 2012_*.txt > train.txt

5. Obtain anchors5.txt in generatedanchors/voc-reproduce folder by executing: ```cmd python genanchors.py -filelist //path//to//voc//filelist/list//train.txt -outputdir generatedanchors/voc-reproduce -num_clusters 5 ```

How to visualize genereted anchors?

After completing the steps above, execute

cmd
python visualize_anchors.py -anchor_dir generated_anchors/voc-reproduce 

Is gen_anchors.py same as YOLOv2 anchor computation?

Yes, almost. Look at the two visualaziations below:

• yolo-voc.cfg anchors are provided by the original author


• yolo-voc-reproduce.cfg anchors computed by genanchors.py <img src= 'https://github.com/Jumabek/darknetscripts/blob/master/generated_anchors/voc-anchors-reproduce/anchors5.png' />

How to get anchors if My input for network is bigger than 416?

Simply change the lines here https://github.com/Jumabek/darknetscripts/blob/master/genanchors.py#L17 to your input dimension. Then compute the anchors.

How to plot YOLO loss?

In order to plot a loss, you first need a log of the darknet train command For example,below command will save the log into log/aggregate-voc-tiny7.log

cmd
darknet.exe detector train data/aggregate-voc-tiny7.data cfg/aggregate-voc-tiny7.cfg  backup/aggregate-voc-tiny7/aggregate-voc-tiny7_21000.weights >> log/aggregate-voc-tiny7.log -gpus 0,1

cmd
python plot_yolo_log.py \\path\\to\\log\\aggregate-voc-tiny7.log