Context

Data science beginners start with curated set of data, but it's a well known fact that in a real Data Science Project, major time is spent on collecting, cleaning and organizing data . Also domain expertise is considered as important aspect of creating good ML models. Being an automobile enthusiast, I tool up this challenge to collect images of two of the popular car models from a used car website, where users upload the images of the car they want to sell and then train a Deep Neural Network to identify model of a car from car images. In my search for images I found that approximately 10 percent of the cars pictures did not represent the intended car correctly and those pictures have to be deleted from final data.

Content

There are 4000 images of two of the popular cars (Swift and Wagonr) in India of make Maruti Suzuki with 2000 pictures belonging to each model. The data is divided into training set with 2400 images , validation set with 800 images and test set with 800 images. The data was randomized before splitting into training, test and validation set.

The starter kernal is provided for keras with CNN. I have also created github project documenting advanced techniques in pytorch and keras for image classification like data augmentation, dropout, batch normalization and transfer learning

Inspiration

1. With small dataset like this, how much accuracy can we achieve and whether more data is always better. The baseline model trained in Keras achieves 88% accuracy on validation set, can we achieve even better performance and by how much.

2. Is the data collected for the two car models representative of all possible car from all over country or there is sample bias .

3. I would also like someone to extend the concept to build a use case so that if user uploads an incorrect car picture of car , the ML model could automatically flag it. For example user uploading incorrect model or an image which is not a car

Source codes and dataset of the research "Solar flare forecasting based on magnetogram sequences learning with MViT and data augmentation". Our work employed PyTorch, a framework for training Deep Learning models with GPU support and automatic back-propagation, to load the MViTv2 s models with Kinetics-400 weights. To simplify the code implementation, eliminating the need for an explicit loop to train and the automation of some hyperparameters, we use the PyTorch Lightning module. The inputs were batches of 10 samples with 16 sequenced images in 3-channel resized to 224 × 224 pixels and normalized from 0 to 1. Most of the papers in our literature survey split the original dataset chronologically. Some authors also apply k-fold cross-validation to emphasize the evaluation of the model stability. However, we adopt a hybrid split taking the first 50,000 to apply the 5-fold cross-validation between the training and validation sets (known data), with 40,000 samples for training and 10,000 for validation. Thus, we can evaluate performance and stability by analyzing the mean and standard deviation of all trained models in the test set, composed of the last 9,834 samples, preserving the chronological order (simulating unknown data). We develop three distinct models to evaluate the impact of oversampling magnetogram sequences through the dataset. The first model, Solar Flare MViT (SF MViT), has trained only with the original data from our base dataset without using oversampling. In the second model, Solar Flare MViT over Train (SF MViT oT), we only apply oversampling on training data, maintaining the original validation dataset. In the third model, Solar Flare MViT over Train and Validation (SF MViT oTV), we apply oversampling in both training and validation sets. We also trained a model oversampling the entire dataset. We called it the "SF_MViT_oTV Test" to verify how resampling or adopting a test set with unreal data may bias the results positively. GitHub version The .zip hosted here contains all files from the project, including the checkpoint and the output files generated by the codes. We have a clean version hosted on GitHub (https://github.com/lfgrim/SFF_MagSeq_MViTs), without the magnetogram_jpg folder (which can be downloaded directly on https://tianchi-competition.oss-cn-hangzhou.aliyuncs.com/531804/dataset_ss2sff.zip) and the output and checkpoint files. Most code files hosted here also contain comments on the Portuguese language, which are being updated to English in the GitHub version. Folders Structure In the Root directory of the project, we have two folders: magnetogram_jpg: holds the source images provided by Space Environment Artificial Intelligence Early Warning Innovation Workshop through the link https://tianchi-competition.oss-cn-hangzhou.aliyuncs.com/531804/dataset_ss2sff.zip. It comprises 73,810 samples of high-quality magnetograms captured by HMI/SDO from 2010 May 4 to 2019 January 26. The HMI instrument provides these data (stored in hmi.sharp_720s dataset), making new samples available every 12 minutes. However, the images from this dataset were collected every 96 minutes. Each image has an associated magnetogram comprising a ready-made snippet of one or most solar ARs. It is essential to notice that the magnetograms cropped by SHARP can contain one or more solar ARs classified by the National Oceanic and Atmospheric Administration (NOAA). Seq_Magnetogram: contains the references for source images with the corresponding labels in the next 24 h. and 48 h. in the respectively M24 and M48 sub-folders. M24/M48: both present the following sub-folders structure: Seqs16; SF_MViT; SF_MViT_oT; SF_MViT_oTV; SF_MViT_oTV_Test. There are also two files in root: inst_packages.sh: install the packages and dependencies to run the models. download_MViTS.py: download the pre-trained MViTv2_S from PyTorch and store it in the cache. M24 and M48 folders hold reference text files (flare_Mclass...) linking the images in the magnetogram_jpg folders or the sequences (Seq16_flare_Mclass...) in the Seqs16 folders with their respective labels. They also hold "cria_seqs.py" which was responsible for creating the sequences and "test_pandas.py" to verify head info and check the number of samples categorized by the label of the text files. All the text files with the prefix "Seq16" and inside the Seqs16 folder were created by "criaseqs.py" code based on the correspondent "flare_Mclass" prefixed text files. Seqs16 folder holds reference text files, in which each file contains a sequence of images that was pointed to the magnetogram_jpg folders. All SF_MViT... folders hold the model training codes itself (SF_MViT...py) and the corresponding job submission (jobMViT...), temporary input (Seq16_flare...), output (saida_MVIT... and MViT_S...), error (err_MViT...) and checkpoint files (sample-FLARE...ckpt). Executed model training codes generate output, error, and checkpoint files. There is also a folder called "lightning_logs" that stores logs of trained models. Naming pattern for the files: magnetogram_jpg: follows the format "hmi.sharp_720s...magnetogram.fits.jpg" and Seqs16: follows the format "hmi.sharp_720s...to.", where: hmi: is the instrument that captured the image sharp_720s: is the database source of SDO/HMI. : is the identification of SHARP region, and can contain one or more solar ARs classified by the (NOAA). : is the date-time the instrument captured the image in the format yyyymmdd_hhnnss_TAI (y:year, m:month, d:day, h:hours, n:minutes, s:seconds). : is the date-time when the sequence starts, and follow the same format of . : is the date-time when the sequence ends, and follow the same format of . Reference text files in M24 and M48 or inside SF_MViT... folders follows the format "flare_Mclass_.txt", where: : is Seq16 if refers to a sequence, or void if refers direct to images. : "24h" or "48h". : is "TrainVal" or "Test". The refers to the split of Train/Val. : void or "_over" after the extension (...txt_over): means temporary input reference that was over-sampled by a training model. All SF_MViT...folders: Model training codes: "SF_MViT_M+_", where: : void or "oT" (over Train) or "oTV" (over Train and Val) or "oTV_Test" (over Train, Val and Test); : "24h" or "48h"; : "oneSplit" for a specific split or "allSplits" if run all splits. : void is default to run 1 GPU or "2gpu" to run into 2 gpus systems; Job submission files: "jobMViT_", where: : point the queue in Lovelace environment hosted on CENAPAD-SP (https://www.cenapad.unicamp.br/parque/jobsLovelace) Temporary inputs: "Seq16_flare_Mclass_.txt: : train or val; : void or "_over" after the extension (...txt_over): means temporary input reference that was over-sampled by a training model. Outputs: "saida_MViT_Adam_10-7", where: : k0 to k4, means the correlated split of the output, or void if the output is from all splits. Error files: "err_MViT_Adam_10-7", where: : k0 to k4, means the correlated split of the error log file, or void if the error file is from all splits. Checkpoint files: "sample-FLARE_MViT_S_10-7-epoch=-valid_loss=-Wloss_k=.ckpt", where: : epoch number of the checkpoint; : corresponding valid loss; : 0 to 4.