A simple tool to generate a grid of thumbnails from a video file. Uses libavformat and libavcodec to read the input file. The frames are scaled to the width specified by -w option (default 150px) and then saved to WEBP output file with configurable quality (-q, default 100 = lossless).
thumbnail-grid [-r num_rows] [-c num_cols] [-w img_width] [-q quality] <input_file> <output_file>
sudo apt install libwebp-dev libavcodec-dev libavutil-dev libavformat-dev libswscale-devmake