You're violating the copyright. In practice, usually nothing until the copyright holder decides to sue you for damages or it gets found during some inspection (but the latter is mostly applicable to companies).

Unsurprisingly I'm not familiar with the ins and outs of Polish copyright law, but in other countries the act of copying something into memory to use it (say copying a frame of video into a frame buffer on a DVD) is not a breach of copyright.

Neither it is in Poland (which you would already know if you read what I wrote more carefully).