Detectron 添加垂直翻转

小灰灰 2021-09-17 17:56 223阅读 0赞

**主要文件：**  
detectron/datasets/json\_dataset.py  
detectron/datasets/roidb.py  
detectron/roi\_data/minibatch.py  
**数据加载流程如下：**  
[图来自][Link 1]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE2MjM0NjEz_size_16_color_FFFFFF_t_70]  
**修改如下：**  
在detectron/datasets/json\_dataset.py文件中添加垂直翻转参数：

entry['flipped_v'] = False

在/detectron/datasets/roidb.py中仿照extend\_with\_flipped\_entries函数添加垂直翻转函数：  
注意，detectron水平翻转后已经将entry加入到roidb中，此时进行垂直翻转，相当于将水平翻转后的图像同样进行的垂直翻转。所以原本200张图像翻转后变成800张。

if cfg.TRAIN.USE_FLIPPED_V:
        logger.info('Appending vertically-flipped training examples...')
        extend_with_flipped_entries_v(roidb, ds)

def extend_with_flipped_entries_v(roidb, dataset):
        flipped_roidb = []
        for entry in roidb:
            height = entry['height']
            boxes = entry['boxes'].copy()
            oldy1 = boxes[:, 1].copy()
            oldy2 = boxes[:, 3].copy()
            boxes[:, 1] = height - oldy2 - 1
            boxes[:, 3] = height - oldy1 - 1
            assert (boxes[:, 3] >= boxes[:, 1]).all()
            flipped_entry = {}
            # dont_copy = ('boxes', 'segms', 'gt_keypoints', 'flipped_v')
            dont_copy = ('boxes', 'flipped_v')
            for k, v in entry.items():
                if k not in dont_copy:
                    flipped_entry[k] = v
            flipped_entry['boxes'] = boxes
            # flipped_entry['segms'] = segm_utils.flip_segms(
            #     entry['segms'], entry['height'], entry['width']
            # )
            # if dataset.keypoints is not None:
            #     flipped_entry['gt_keypoints'] = keypoint_utils.flip_keypoints(
            #         dataset.keypoints, dataset.keypoint_flip_map,
            #         entry['gt_keypoints'], entry['width']
            #     )
            flipped_entry['flipped_v'] = True
            flipped_roidb.append(flipped_entry)
        roidb.extend(flipped_roidb)

在detectron/roi\_data/minibatch.py文件中添加图像像素的翻转：

if roidb[i]['flipped_v']:
        im = im[::-1, :, :]

最好在配置文件中添加：

USE_FLIPPED_V: True

[Link 1]: https://blog.csdn.net/zziahgf/article/details/79672786
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE2MjM0NjEz_size_16_color_FFFFFF_t_70]: /images/20210520/e069085bb3044dc9b2dfddb79366f93c.png