tx and ty are translation. I think a and d are scale and b and c are some function of rotation. I have videos that are flipped and rotated using arbitrary matrices. How can I make them right-side-up ...

This is a subject I struggled with the first time I took it. Ironically, this was the engineering version of it. It wasn't until I took the rigorous, axiomatic version that everything clicked.

If \(A\) is a \(3\times 3\) matrix then we can apply a linear transformation to each rgb vector via matrix multiplication, where \([r,g,b]\) are the original values ...