Description

This repository contains scripts to generate holograms using images and their depth maps.

Installing required libraries

Please make sure that you have the latest odak installed on your system. You can find more information on installing odak in this link.

Preparing images and depth maps

Make sure that you have images and their depth maps in separate folders. In our case, we keep a dataset directory in our home directory, where there are images and depths folders inside it. For example, we have a directory called ~/datasets/div2k_w_depth_4k, and there are ~/datasets/div2k_w_depth_4k/images and ~/datasets/div2k_w_depth_4k/depths folders inside it. To create these folders, we downloaded DIV2K dataset from here. We used a monocular depth estimation model, DenseDepth, to predict the depth maps of our images. Once we have the images and depths folder filled, we resize these images to the required resolution by our spatial light modulator. Below, you find a script to resize all the images and depths, which we placed inside ~/datasets/div2k_w_depth_4k/.

for f in `find . -name "*.png"`
do
    mogrify -resize 4094x2400! $f
done

Note that you can install mogrify with a simple sudo apt-get install mogrify. Note that this codebase likes working with png files.

Hologram generation

Now that we have images and their corresponding depths, we can go ahead and generate holograms using realistic_defocus library located in this link. Imagine you have hologram_dataset repository under ~/repos/hologram_dataset, in this case, make sure to clone realistic_defocus under ~/repos/realistic_defocus. For example, in realistic_defocus, you will find two settings file for two different spatial light modulators as settings/holoeye.txt and settings/jasper.txt. If you are also using the same spatial light modulator, feel free to use them or modify them for your needs.

Our next step is to plug everything together, let's say you are interested in generating hologram at 4094 x 2400 resolution. To do this, there are some variables that you have to carefully adjust for your case:

--settings_filename
--rgb_directory
--depth_directory
--key png
--output_dataset_directory
--generator

These are the variables that you want to adjust in that compile_set_4k.py. settings_filename should point to the location where your settings file is. This is typically a settings file for realistic_defocus, such as settings/jasper.txt under realistic_defocus. rgb_directory is the location where your images are. depth_directory is the location where your depths are. key defines the file extension of your images and depth files. generator defines the generator that you want to use for generating your dataset (holohdr or realistic_defocus). Finally, output_dataset_directory is the location where you will be saving all the holograms. For remaining keys that we haven't explained here, please consult python3 main.py --help.

Now that you have configured everything as intended, you can start generating holograms by using the following syntax in your shell:

CUDA_VISIBLE_DEVICES=1 python3 compile.py --settings_filename ../realistic_defocus/settings/jasper.txt --rgb_directory ~/datasets/div2k_w_depth_4k/train/images/ --depth_directory ~/datasets/div2k_w_depth_4k/train/depths/ --key *.png --output_dataset_directory ~/datasets/holograms_4k/ --count_offset 0 --generator realistic_defocus

or for holohdr, you can use the following:

python3 compile.py --settings_filename ../holohdr/settings/jasper.txt --rgb_directory ~/datasets/div2k_w_depth_4k/train/images/ --depth_directory ~/datasets/div2k_w_depth_4k/train/depths/ --output_dataset_directory ~/datasets/holograms_jasper_rgb_conventional --key *.png --count_offset 0 --generator holohdr

Note that CUDA_VISIBLE_DEVICES helps you to choose the GPU that you want to use for this calculation. Please also remember that the default GPU is zero, CUDA_VISIBLE_DEVICES=0. In the above example, the second GPU is used. For example, if you need to generate a hologram dataset in high-definition for holoeye spatilal light modulators, you can use the following command:

python3 compile.py --settings_filename ../realistic_defocus/settings/holoeye.txt --rgb_directory ~/datasets/div2k_w_depth_hd/train/images/ --depth_directory ~/datasets/div2k_w_depth_hd/train/depths/ --key *.png --output_dataset_directory ~/datasets/holograms_hd/ --count_offset 0 --generator realistic_defocus

or for holohdr, you can use the following:

python3 compile.py --settings_filename ../holohdr/settings/holoeye.txt --rgb_directory ~/datasets/div2k_w_depth_hd/train/images/ --depth_directory ~/datasets/div2k_w_depth_hd/train/depths/ --output_dataset_directory ~/datasets/holograms_hd_rgb_conventional --key *.png --count_offset 0 --generator holohdr 

Support

We tested the explained workflow in an Ubuntu operating system. If you have any questions regarding the descriptions and usage, please do not hesitate to use issues section for your queries.