add readme

Author: yfeng95

README.md

@@ -0,0 +1,97 @@
+# face3d: python tools for processing 3d face
+
+## Introduction
+
+ I organize this repo just for fun & my personal research use. 
+
+Hope this helps and you can enjoy it. : )
+
+
+
+## Structure
+
+```python
+# Since triangle mesh is the most popular representation of 3D face, the main part is mesh processing.
+mesh/             # written in python(numpy)
+|  io.py                 # read & write obj
+|  vis.py                # plot mesh
+|  transform.py          # transform mesh & estimate matrix
+|  light.py              # add light & estimate light(to do)
+|  render.py             # obj to image using rasterization render
+
+# When can not use vercorization to optimize, loop in python is too slow to use. So write core parts(loop) in c++, then use cython to compile it.
+mesh_cython/      # written in c++(cython)
+|  render.py             # the same API as in mesh/render.py, with faster speed.
+|  light.py              # the same API as in mesh/light.py, with faster speed.
+|  mesh_core*            # c++ codes of core parts.
+
+# 3DMM is one of the most popular methods to generate & reconstruct 3d face.
+morphabel_model/  # witten in python(numpy)
+|  morphable_model.py    # morphable model class: generate & fit
+|  fit.py                # estimate shape&expression parameters. 3dmm fitting.
+|  load.py               # load 3dmm data
+```
+
+
+## Examples:
+
+* **3dmm**.  `run examples/2_3dmm.py`
+
+  left: random examples generated by 3dmm
+
+  right: 3d face generated by fitted 3dmm&pose  parameters using 68 key points
+
+![](examples/results/3dmm/generated.jpg)![](examples/results/3dmm/fitted.jpg)
+
+* **transform.**  `python examples/3_transform.py`
+
+![](examples/results/transform/obj.gif)![](examples/results/transform/camera.gif)
+
+* **light**.   `python examples/4_light.py`
+
+![](examples/results/light/position.gif)
+
+* **image map** `python examples/6_image_map.py`
+
+![](examples/results/image_map/depth.jpg) ![](examples/results/image_map/pncc.jpg) ![](examples/results/image_map/uv_coords.jpg)
+
+* **uv map** `python examples/7_uv_map.py`
+
+![](examples/results/uv_map/uv_texture_map.jpg)![](examples/results/uv_map/uv_position_map.jpg)![](examples/results/uv_map/image.jpg)
+
+
+
+## Getting Started
+
+### Prerequisite
+
+- Python 3+ (numpy, skimage, scipy)
+
+- Python packages:
+  * numpy 
+  * skimage (for reading&writing image)
+  * scipy (for loading mat)
+  * Cython (for compiling c++ files)
+
+- BFM Data
+
+  see [Data/BFM/readme.md](Data/BFM/readme.md)
+
+### Usage
+
+1. Clone the repository
+
+```bash
+git clone https://github.com/YadiraF/face3d
+cd face3d
+```
+
+2. Compile c++ files(ignore if you use numpy version)
+
+```bash
+cd face3d/mesh_cython
+python setup.py build_ext -i 
+```
+
+3. Run examples
+