---
license: apache-2.0
task_categories:
  - depth-estimation
tags:
  - mars
  - hirise
  - dtm
  - litdata
  - streaming
pretty_name: Mars HiRISE DTM (LitData Streaming)
dataset_info:
  config_name: 18054274757e4a31
  splits:
    - name: train
    - name: val
    - name: test
---

# Mars HiRISE DTM — LitData Streaming Dataset

Pre-processed Mars HiRISE orthoimage + DTM patches in
[LitData](https://github.com/Lightning-AI/litdata) optimized streaming format.

## Quick Start

```python
from litdata import StreamingDataset

# Stream directly from HuggingFace — no full download needed
train_ds = StreamingDataset(input_dir="hf://datasets/SuperComputer/mars_hirise_dtm_processed-18054274757e4a31/train")
val_ds   = StreamingDataset(input_dir="hf://datasets/SuperComputer/mars_hirise_dtm_processed-18054274757e4a31/val")
test_ds  = StreamingDataset(input_dir="hf://datasets/SuperComputer/mars_hirise_dtm_processed-18054274757e4a31/test")

sample = train_ds[0]

# Core Tensors
print(sample["image"].shape)        # (3, H, W) float16
print(sample["dtm"].shape)          # (3, H, W) float16
print(sample["confidence"].shape)   # (1, H, W) float16

# Physical / Lighting Parameters
print(sample["sun_vector"].shape)   # (3,)      float32
print(sample["intensity"])          # float32
print(sample["ambient"])            # float32

# Original / Unnormalized Data
print(sample["original_image"].shape) # (C, H, W) float16
print(sample["original_dtm"].shape)   # (1, H, W) float16
print(sample["trend_params"].shape)   # (3,)      float16

# Normalization / Processing Metadata
print(sample["residual_scale"])     # float32
print(sample["raw_residual_p98"])   # float32
print(sample["key"])                # str (e.g., "left_red")
```

## Fields

During extraction, model inputs are quantized to `float16` to optimize streaming bandwidth. Physical lighting parameters remain `float32`.

| Key                | Dtype   | Shape      | Description                                    |
|--------------------|---------|------------|------------------------------------------------|
| `image`            | float16 | (3, H, W)  | Normalized HiRISE orthoimage [-1, 1]           |
| `dtm`              | float16 | (3, H, W)  | Normalized DTM elevation                       |
| `confidence`       | float16 | (1, H, W)  | Binary valid data mask (eroded/cleaned)        |
| `sun_vector`       | float32 | (3,)       | Estimated sun direction (OLS, unit-normalized) |
| `intensity`        | float32 | scalar     | Estimated sun intensity                        |
| `ambient`          | float32 | scalar     | Estimated ambient light                        |
| `original_image`   | float16 | (C, H, W)  | Unnormalized resized orthoimage                |
| `original_dtm`     | float16 | (1, H, W)  | Unnormalized resized DTM elevation             |
| `trend_params`     | float16 | (3,)       | LSQR detrend parameters for the DTM plane      |
| `residual_scale`   | float32 | scalar     | Normalization scale applied to the DTM residual|
| `raw_residual_p98` | float32 | scalar     | 98th percentile of the raw topographic residual|
| `key`              | string  | scalar     | Orthoimage source used (e.g., left_red)        |


## Preprocessing Configuration

**Config Hash:** `18054274757e4a31`

This dataset was generated with the following pipeline parameters:

```yaml
hirise:
  root: /scratch/mars_hirise_dtm
  include_ortho: true
  ortho_type: RED
  ortho_scale: null
  download: false
  reuse_cache: true
  target: null
  bbox:
  - -120
  - -30
  - 150
  - 30
sampler:
  size: 0.018
  length: null
resolution: 512
dtm_normalization: relative

```