Here is a list of all files with brief descriptions:

[detail level 123]

src
cnn
cnn.c	CNN implementation: initialisation, forward pass, backward pass, SGD-with-momentum update
cnn.h	Convolutional Neural Network for A–Z character recognition
dataset.c	Training dataset loader with optional POSIX thread parallelism
dataset.h	Training dataset loader
model.c	Binary save/load of CNN weights and latest-model discovery
model.h	Binary serialisation and deserialisation of CNN weights
preprocess
image.c	Image preprocessing pipeline using libpng (no SDL2_image required)
image.h	Image loading, preprocessing, and normalisation
segment
segment.c	Letter segmentation via connected-component analysis and grid detection
segment.h	Letter segmentation: detect crossword grid and extract letter cells
solver
solver.c	8-direction crossword word-search solver
solver.h	Crossword word-search solver: find words in a 2-D character grid in all 8 directions
gui_main.c	SDL2 graphical interface for the OCR crossword solver
solve_main.c	Entry point for the OCR + crossword-solver binary
train_main.c	Entry point for the CNN training binary