Mmcv

New Features

- New method ``import_modules_from_strings`` for import customized modules when loading config from file. (606)
- Add switch for ``onnx exporter`` to get different ONNX model according to the backend. (607)
- Add Sync buffer in CheckpointHook. (588)


Improvements

- Refactor logger hooks. (605)
- Skip ``opencv`` requirement if it's already installed in the env. (616)
- Serveral updates regarding Windows and unittests. (586)


Bug Fixes

- Fix bug in resuming dict version of optimizers when using epoch based runner. (610)
- Fix iter-time-hook bug when meeting iter-based runner. (623)

Bug Fixes

- Fix wrappers version comparison bug. (602)
- Revert DCN to fix the bug introduced in https://github.com/open-mmlab/mmcv/pull/565. (#597)

New Features

- Add a `RUNNERS` registry and `build_runner` method. (570)
- Support to specify LR of DCN's conv_offset. (344)

Improvements

- merge the calling of train/val_step and batch_processor into run_iter (553)
- Add the missing `by_epoch` arg for `MlflowLoggerHook` and `WandbLoggerHook`. (576)
- Add `aligned=True` for torchvision roi_align. (581)
- Adopt the new URL https://download.openmmlab.com. (#583)
- Register deconv in `CONV_LAYERS`. (582)
- Log grad norm in fp16 optimizer hook. (584)

Bug Fixes

- Fix fp16_optimizer state bug. (580)
- Fix the pytorch version comparison in op wrappers. (572)

New Features

- Implement `Conv2dAdaptivePadding`, which is the same op as 2D convolution in tensorflow with `padding` set to "same". (529)
- Support reading video from url (531)
- Add `imtranslate`, `imequalize`, `adjust_color`, `adjust_brightness`, `adjust_contrast` augmentation. (538, 542, 543, 546)

Improvements

- Add switch for onnx exporter. (564)
- Allow `type` to be `default_args` in `build_from_cfg`. (558)
- Expose `wrap_fp16_model` to mmcv.runner. (555)
- Move op wrappers into bricks and use wrappers in registry (550)
- Support multiple interpolation modes for `imrotate` (545)

Bug Fixes

- Fix the init method of deprecated wrappers. (567)
- Fix DCN bug in parrots. (562, 563, 565)
- Use copy instead of symlink on windows. (557)
- Remove assertion for batch size and samples_per_gpu. (549)
- Fix compilation bug in windows and add instruction for windows. (540)
- Fix missing pad_val in impad_to_multiple. (539)

New Features
- Add Swish activation (522)
- Add shear augmentation (526)
- Support loading checkpoints in MMClassification with the scheme `mmcls://` (511)

Improvements
- Allow `imshow_det_bboxes()` to return the image with bboxes. (527)
- Add more default types for json dump (536)

New Features
- Add `collect_env()` to collect environment info.
- Add `import_modules_from_strings()` to import modules from a string list.

Improvements
- Support splitting in `batched_nms` when box number is too large.
- Support pickling Config.
- Add `diagonal` flip mode.

Bug fixes
- Fix regex bugs in windows paths.
- Fix windows compilation issue.
- Fix inconsistent return types in pybind11 function prototypes.