Two books I loved during my digital signal processing studies (especially in the audio field):
- Introduction to Computer Music [0] by Nick Collins: very focused on audio programming for musical applications but you can easily extrapolate for other domains. Lots of pseudo-code algorithms are provided.
- The Scientist and Engineer s Guide to Digital Signal Processing [1] by Steven W. Smith: the bread and butter for everything concept related to DSP. Everything is explained in a crystal-clear fashion, lots of sample code to get you started with digital filters and analysis (although written in BASIC but easily translatable to C/C++ or even Python).