I come from an engineering angle and am only superficially familiar with https://dspguide.com/ https://dspguide.com/ which I found useful for my field. DSP is

I come from an engineering angle and am only superficially familiar with https://dspguide.com/ https://dspguide.com/ which I found useful for my field. DSP is a broad field, from audio design to high speed communication to image processing. An introductory book (see above) will touch many subjects, but to go deeper you will have to find books dedicated to that specific field.