coco数据集的处理

ssd中readme.md提供了对Coco的处理

ssd/caffe/data/coco/

### Preparation

1. Download Images and Annotations from [MSCOCO](http://mscoco.org/dataset/#download). By default, we assume the data is stored in `$HOME/data/coco`

2. Get the coco code. We will call the directory that you cloned coco into `$COCO_ROOT`

  ```Shell

  git clone https://github.com/weiliu89/coco.git
  cd coco

  git checkout dev

  ```

3. Build the coco code.

  ```Shell

  cd PythonAPI

  python setup.py build_ext --inplace

  ```

4. Split the annotation to many files per image and get the image size info.

  ```Shell

  # Check scripts/batch_split_annotation.py and change settings accordingly.

  python scripts/batch_split_annotation.py

  # Create the minival2014_name_size.txt and test-dev2015_name_size.txt in $CAFFE_ROOT/data/coco

  python scripts/batch_get_image_size.py

  ```

5. Create the LMDB file.

  ```Shell

  cd $CAFFE_ROOT

  # Create the minival.txt, testdev.txt, test.txt, train.txt in data/coco/

  python data/coco/create_list.py

  # You can modify the parameters in create_data.sh if needed.

  # It will create lmdb files for minival, testdev, test, and train with encoded original image:

  #   - $HOME/data/coco/lmdb/coco_minival_lmdb

  #   - $HOME/data/coco/lmdb/coco_testdev_lmdb

  #   - $HOME/data/coco/lmdb/coco_test_lmdb

  #   - $HOME/data/coco/lmdb/coco_train_lmdb

  # and make soft links at examples/coco/

  ./data/coco/create_data.sh

  ```