Update DATASET_ZOO.md

DATASET_ZOO.md

@@ -1,9 +1,9 @@
 # Dataset Zoo
 We provide several relevant datasets for training and evaluating the Joint Detection and Embedding (JDE) model. 
 Annotations are provided in a unified format. If you want to use these datasets, please **follow their licenses**, 
-and if you use these datasets in your research, please cite the original work (you can find the bibtex in the bottom).
+and if you use these datasets in your research, please cite the original work (you can find the BibTeX in the bottom).
 ## Data Format
-All the dataset has the following structrue:
+All the dataset has the following structure:
 ```
 Caltech
    |——————images
@@ -15,14 +15,14 @@ Caltech
             |—————— ...
             └——————0000N.txt
 ```
-Every image corresponds to an annation text. Given an image path, 
+Every image corresponds to an annotation text. Given an image path, 
 the annotation text path can be easily generated by replacing the string `images` with `labels_with_ids` and replacing `.jpg` with `.txt`.
 
 In the annotation text, each line is a bounding box and has the following format,
 ```
 [class] [identity] [x_center] [y_center] [width] [height]
 ```
-The field `[class]` is not used in this project since we only care about a single class, i.e., pedestrian here. 
+The field `[class]` should be `0`. Only single-class multi-object tracking is supported in this version. 
 
 The field `[identity]` is an integer from `0` to `num_identities - 1`, or `-1` if this box has no identity annotation.