in modified_mmseg/datasets/pipelines/transforms.py [0:0]
def _random_scale(self, results):
"""Randomly sample an img_scale according to ``ratio_range`` and
``multiscale_mode``.
If ``ratio_range`` is specified, a ratio will be sampled and be
multiplied with ``img_scale``.
If multiple scales are specified by ``img_scale``, a scale will be
sampled according to ``multiscale_mode``.
Otherwise, single scale will be used.
Args:
results (dict): Result dict from :obj:`dataset`.
Returns:
dict: Two new keys 'scale` and 'scale_idx` are added into
``results``, which would be used by subsequent pipelines.
"""
if self.ratio_range is not None:
if self.img_scale is None:
h, w = results['img'].shape[:2]
scale, scale_idx = self.random_sample_ratio((w, h),
self.ratio_range)
else:
scale, scale_idx = self.random_sample_ratio(
self.img_scale[0], self.ratio_range)
elif len(self.img_scale) == 1:
scale, scale_idx = self.img_scale[0], 0
elif self.multiscale_mode == 'range':
scale, scale_idx = self.random_sample(self.img_scale)
elif self.multiscale_mode == 'value':
scale, scale_idx = self.random_select(self.img_scale)
else:
raise NotImplementedError
results['scale'] = scale
results['scale_idx'] = scale_idx