SolvedYolo_mark Specific format of annotation

Could you please tell me the format of annotation? I generated my own dataset and I want to train it. I know exactly where my objects are in the image. In that case, I don't want to manually generate annotation. I can write some code to do it for me if I know the format of annotation for YOLO v3. Thank you

52 Answers

✔️Accepted Answer

.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 from 0 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 will be created 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

https://github.com/AlexeyAB/darknet#how-to-train-to-detect-your-custom-objects

  1. Create file obj.names in the directory build\darknet\x64\data\, with objects names - each in new line

  2. Create file obj.data in the directory build\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/
  1. Put image-files (.jpg) of your objects in the directory build\darknet\x64\data\obj\

  2. You should label each object on images from your dataset. Use this visual GUI-software for marking bounded boxes of objects and generating annotation files for Yolo v2 & v3: https://github.com/AlexeyAB/Yolo_mark

It will 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 from 0 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 will be created 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
  1. Create file train.txt in directory build\darknet\x64\data\, with filenames of your images, each filename in new line, with path relative to darknet.exe, for example containing:
data/obj/img1.jpg
data/obj/img2.jpg
data/obj/img3.jpg

Other Answers:

@sarratouil thank you for the support

Thank you for your reply. I think I found the bug. I labelled my object wrong somehow which leads to useless traning.

@Riankk123
Format is already stated here: #60 (comment)

darknet_format