Deep Deghosting HDR:

This Repository contains code and pretrained models for HDR version of our paper : A Fast, Scalable, and Reliable Deghosting Method for Extreme Exposure Fusion accepted at ICCP, 2019 .
It has been tested on GTX 1080ti and RTX 2070 GPUs and tensorflow 1.13 and contains scripts for both inference and training .

The project was built on Python-3.6.7 and requires following packages

• affine==2.2.2
• matplotlib==3.0.2
• numpy==1.16.2
• opencv-python==4.0.0.21
• Pillow==5.4.1
• scikit-image==0.14.2
• scikit-learn==0.20.2
• scipy==1.2.1
• tensorboard==1.13.1
• tensorflow-gpu==1.13.1
• termcolor==1.1.0
• tqdm==4.31.1

Inference Instructions:

Use script infer.py to perform inference. The script expects :

1. A directory containing set of multi-exposure shots, lebeled as 1.tif, 2.tif, 3.tif and a file exposure.txt listing out EV gaps between the images.
   
2. Pretrained flow, refinement and fusion models.
   
3. The choice of fusion model: tied (works for any number of images) or untied model (fixed number of images).
   
4. The image to choose as reference (1st or 2nd)
   
5. GPU id to choose the gpu to run the script on.
   

Note :

1. To fit everything in single script, unofficial PWC-NET implementation available in this repository has been used, but you can use any other official implementation to precompute flows as well.
   
2. The script is meant for 3 multi-exposure shots but can easily be extended to arbitrary number of inputs along similar lines.
   

Sample Command:

python infer.py --source_dir ./data_samples/test_set --fusion_model tied --ref_label 2 --gpu 1

Training Instructions:

Script train_refine.py trains refinement model.

Description of inputs to the script:

1. train_patch_list : list of training images. Download them from (Link to be updated soon). Use a pretrained flow algorithm to precompute flow as numpy files and save them as flow_21.npy and flow_23.npy. Refer to file data_samples/refine_train.txt and directory data_samples/refine_data for sample
   
2. val_patch_list : list of test images organized similarly.
   
3. logdir : checkpoints and tensorboard visualizations get logged here.
   
4. iters : number of iterations to train model for.
   
5. image_dim : dimensions of input patch during training
   
6. batch_size : ---do----
   
7. restore : 0 to start afresh, 1 to load checkpoint
   
8. restore_ckpt: if restore was 1, path to checkpoint to load
   
9. gpu : GPU id of the device to use for training.
   

Script train_static_fusion.py trains fusion model.

Description of inputs to the script:

Note: Use pretrained refinement model to generate static version of training images

1. train_patch_idx : list of training images. Download them from here. Refer to file data_samples/fusion_train.txt and directory data_samples/fusion_data for sample.
   
2. test_patch_idx : list of test images.
   
3. fusion_model : choose between untied and tied fusion model.
   
4. logdir : checkpoints and tensorboard visualizations get logged here.
   
5. iters : number of iterations to train model for.
   
6. lr : initial learning rate
7. image_dim : dimensions of input patch during training
   
8. batch_size : ---do----
   
9. restore : 0 to start afresh, 1 to load checkpoint
   
10. restore_ckpt: if restore was 1, path to checkpoint to load
    
11. gpu : GPU id of the device to use for training.
    
12. hdr : set 1 if you want to concatenate corresponding hdr with inputs ldrs
    
13. hdr_weight : weight to mse loss between tonemapped hdr outputs.
    
14. ssim_weight : weight for MS-SSIM loss
    
15. perceptual_weight: Weight for perceptual loss