This was an Adobe Research intern project performed by Brian Davis that resulted in Text and Style Conditioned GAN for Generation of Offline Handwriting Lines published at BMVC 2020. Since the end of the internship, Brian has greatly improved upon the method, and the official code repo for the paper is hosted separately.
The goal of this project is to extract a style vector from handwriting example image(s) (lines), and then, conditioned on that style vector and some given text, generate new handwriting images.
- Python 3.x
- PyTorch 1.1 (greater may have some errors that need fixed still)
To use deformable convs you'll need to copy this repo in the main directory: https://github.com/open-mmlab/mmdetection
Install using this command in the mmdetection directory: python setup.py develop
This code only compiles on a GPU version Pytorch, CPU-only does not work.
Usage: python generate.py -c path/to/snapshot.pth -l list_file.json
The list file has the following format:
It is a list of "jobs":
[
{
"style": ["path/image1", "path/image1",...],
"text": ["generate this text", "and this text", ...],
"out": ["path/save/this", "path/save/that", ...]
},
{
another one...
}
]
All of the style images are appended together to extrac a single style and it is used to generate the given texts.
You can do a single image using the flags -s "path/image1 path/image2" -t "generate this text" -o path/save/this.
If you want to interpolate, add "interpolate":0.1" to the job. The float is the interpolation step size. It must have only one text (and out path) and each style image will have a style extracted from it individually. The interpolation will be between each of the images' styles (and back to the first one).
Running python new_eval.py -c path/to/checkpoint.pth will run the validation set and return the loss and CER
To write images, use these flags: -d ../out -n 20 -e [recon,recon_gt_mask,mask,gen,gen_mask] -a data_loader=short=1
-d specifies the output directory, -n specifies how many images to output
`-e' has which images to write:
recon: reconstruction using predicted maskrecon_gt_mask: reconstruction using GT maskmask: predicted mask for reconstructiongen: instance generated using novel style- 'gen_mask`: mask generated for above instance
-a flag allows changing of the config file. use key=nested_key=value,another_key=value format. The data_loader=short=1 above prints less examples per author (more authors)
You can also use this script to save style vectors (for use in umap_styles.py): -a save_style=path/to/save/style.pkl,saveStyleEvery=5000
This will only save the validation set is used alone (in val_style.pkl). If training set is desired, use -n 99999999, or whatever the size of your dataset is.
It saves a (val_)style.pkl.# every saveStyleEvery instances. These are automatically globbed by umap_styles.py if you pass it (val_)style.pkl. Make saveStyleEvery big if you don't want this.
Config files are in .json format.
{
"name": "long_Gskip", #name for saving
"cuda": true, #use GPUs
"gpu": 0, #only single GPU supported
"save_mode": "state_dict", #can change to save whole model
"override": true, #if resuming, replace config file
"super_computer":false, #whether to mute log output
"data_loader": {
"data_set_name": "AuthorHWDataset", #class name
"data_dir": "/path/to/data/",
"Xdata_dir": "../data/IAM/",
"batch_size": 1,
"a_batch_size": 2,
"shuffle": true,
"num_workers": 2,
"img_height": 64,
"max_width": 1400,
"char_file": "./data/IAM_char_set.json",
"mask_post": ["thresh","dilateCircle","errodeCircle"],
"mask_random": false,
"spaced_loc": "../saved/spaced/spaced.pkl"
},
"validation": {
"shuffle": false,
"batch_size": 3,
"a_batch_size": 2,
"spaced_loc": "../saved/spaced/val_spaced.pkl"
},
"lr_scheduler_type": "none",
"optimizer_type": "Adam",
"optimizer": {
"lr": 0.00001,
"weight_decay": 0,
"betas": [0.5,0.99]
},
"optimizer_type_discriminator": "Adam", #seperate optimizer for discriminators
"optimizer_discriminator": {
"lr": 0.00001,
"weight_decay": 0,
"betas": [0,0.9]
},
"loss": { #adversarial losses (generative and discriminator) are hard coded and not specified here
"auto": "pyramidL1Loss",
"key": "pushMinDist",
"count": "MSELoss",
"mask": "HingeLoss",
"feature": "L1Loss",
"reconRecog": "CTCLoss",
"genRecog": "CTCLoss",
"genAutoStyle": "L1Loss"
},
"loss_weights": { #multiplied to loss to balance them
"auto": 1,
"discriminator": 0.1,
"generator": 0.01,
"key": 0.001,
"count": 0.1,
"mask": 0.1,
"mask_generator": 0.01,
"mask_discriminator": 0.01,
"feature": 0.0000001,
"reconRecog": 0.000001,
"genRecog": 0.0001,
"style_discriminator": 0.1,
"style_generator": 0.01,
"genAutoStyle": 0.1
},
"loss_params": #additional params passed directly to function
{
"auto": {"weights":[0.4,0.3,0.3],
"pool": "avg"},
"key": {"dist":"l1",
"thresh": 1.0},
"mask": {"threshold": 4}
},
"metrics": [], #unused
"trainer": {
"class": "HWWithStyleTrainer",
"iterations": 700000, #Everything is iterations, because epochs are weird.
"save_dir": "../saved/",
"val_step": 2000, #how frequently to run through validation set
"save_step": 5000, #how frequently to save a seperate snapshot of the training & model
"save_step_minor": 250, #how frequently to save a "latest" model (overwrites)
"log_step": 100, #how frequently to print training stats
"verbosity": 1,
"monitor": "loss",
"monitor_mode": "none",
"space_input": true,
"style_together": true, #append images together (by author) to extract style vector
"use_hwr_pred_for_style": true, #use raw HWR pred as input to style extraction (instead of cheating with aligned GT)
"hwr_without_style":true, #Change to true to pass style vector to HWR model
"slow_param_names": ["keys"], #Multiplies weight updates by 0.1 for param names containing any in the list
"curriculum": { #Training curriculum
"0": [["auto"],["auto-disc"]], # iteration to start at: list of list, iteration cycle and components/losses for each iteration
"1000": [["auto", "auto-gen"],["auto-disc"]],
"80000": [["count","mask","gt_spaced","mask-gen"],["auto-disc","mask-disc"]],
"100000": [ [1,"count","mask","gt_spaced","mask-gen"],
["auto","auto-gen","count","mask","gt_spaced","mask_gen"],
["auto","auto-mask","auto-gen","count","mask","gt_spaced","mask_gen"],
[2,"gen","gen-auto-style"],
[2,"disc","mask-disc"],
[2,"auto-disc","mask-disc"]]
},
"balance_loss": true, #use balancing between CTC loss and reconstruction/adversarial loss
"interpolate_gen_styles": "extra-0.25", #interpolate instead of pulling styles out of a hat. This tells it to possibly extrapolate by 0.25 of the distance between the styles
"text_data": "data/lotr.txt", #Text file for generation
"use_learning_schedule": false
},
"arch": "HWWithStyle",
"model": {
"num_class": 80,
"generator": "SpacedWithMask",
"gen_dim": 128,
"gen_n_res1": 2,
"gen_n_res2": 3,
"gen_n_res3": 2,
"gen_use_skips": true,
"hwr": "CRNN_group_norm_softmax",
"pretrained_hwr": "../saved/IAM_hwr_softmax_aug/checkpoint-latest.pth",
"hwr_frozen": true,
"style": "new",
"style_norm":"group",
"style_activ":"relu",
"style_dim": 256,
"num_keys": 64,
"global_pool": true,
"discriminator": "two-scale-better more low global",
"spacer": "duplicates",
"create_mask": true,
"mask_discriminator": "with derivitive"
}
}
Modify the configurations in .json config files, then run:
python train.py --config config.json
You can resume from a previously saved checkpoint by:
python train.py --resume path/to/checkpoint
You can overwrite th config from the sanpshot with
python train.py --config new_config.json --resume path/to/checkpoint
The checkpoints will be saved in save_dir/name/.
The config file is saved in the same folder. (as a reference only, the config is loaded from the checkpoint)
Note: checkpoints contain:
{
'arch': arch,
'epoch': epoch,
'logger': self.train_logger,
'state_dict': self.model.state_dict(),
'optimizer': self.optimizer.state_dict(),
'monitor_best': self.monitor_best,
'config': self.config
}