Android apps that allow you to play videos off the file system but speed up playback only between subtitles?

I want to plow through more dialogue. My current player has the option to skip silence, useful for lectures but most media has music or ambience or fight noises between dialogue.

Anyone found any? I believe language reactor has it but that's an extension and I haven't figured out how to get videos on my file system play in any browser app that has extension support or not.