Update README.md

README.md

@@ -29,4 +29,69 @@ task_categories:
 
 \[[arXiv Paper](https://www.arxiv.org/pdf/2502.13130)\]   \[[Project Page](https://microsoft.github.io/Magma/)\]   \[[Hugging Face Paper](https://huggingface.co/papers/2502.13130)\]   \[[Github Repo](https://github.com/microsoft/Magma)\]   \[[Video](https://www.youtube.com/watch?v=SbfzvUU5yM8)\] 
 
-</div>
+</div>
+
+## Introduction
+
+This dataset contains the robotic manipulation data used in Magma pretraining. For fair comparison, we followed OpenVLA to use the data mix "siglip-224px+mx-oxe-magic-soup".
+
+The dataset is organized by following source datasets, with each source containing one or more arrow files:
+
+| Folder                                                |   Number of Shards |
+|:------------------------------------------------------|-------------------:|
+| ego4d      |                  15 |
+| sthv2    |                  6 |
+| instruct_video    |                  14 |
+
+
+### Features
+
+In addition to the default features, we extracted the visual traces of future 16 frames for each frame. The dataset contains the following fields:
+
+- `dataset_name`: Original source dataset name
+- `video_name`: video name
+- `task_string`: Description of the task
+- 'start_time': starting time stamp for the video segment
+- 'end_time': ending time stamp for the video segment
+- `frame_index`: starting index of the frame in the video segment
+- `height`: resized image height for visual trace extraction
+- 'width': resized image width for visual trace extraction
+- `trace`: Robot trajectory trace (serialized numpy array)
+- `trace_visibility`: Visibility mask for the trace (serialized numpy array)
+
+## Dataset Loading
+
+### Full Dataset Load
+
+```py
+from datasets import load_dataset
+dataset = load_dataset("MagmaAI/Magma-Video-ToM", streaming=True, split="train")
+```
+
+### Individual Dataset Load
+or specify a dataset by:
+
+```py
+from datasets import load_dataset
+dataset = load_dataset("MagmaAI/Magma-Video-ToM", data_dir="sthv2", streaming=True, split="train")
+```
+
+### Sample Decoding
+
+```py
+# Helper function to deserialize binary fields
+def deserialize_array(bytes_data):
+    return pickle.loads(bytes_data)
+
+# Helper function to convert binary image data to PIL Image
+def bytes_to_image(image_bytes):
+    return Image.open(io.BytesIO(image_bytes))
+
+for i, example in enumerate(dataset):   
+    # decode trace: 1 x 16 x 256 x 2
+    trace = deserialize_array(example['trace'])
+    # decode trace visibility: 1 x 16 x 256 x 1
+    trace_visibility = deserialize_array(example['trace_visibility'])
+```
+
+**NOTE**: the temporal length of traces for video data is 16 as we excluded the starting frame. For all robotics data, it is 17 as we did not exclude the starting frame.