Convert h264 to spx

What is the difference between .h264 and .spx?

Description: The H.264 Encoded Video File, commonly referred to by its file extension .h264, is a digital video file format that utilizes the H.264 codec. This codec, also known as MPEG-4 Part 10 or AVC (Advanced Video Coding), is widely recognized for its high compression efficiency, providing high-quality video at relatively low bitrates. This makes it ideal for use in various applications, from streaming video services and Blu-ray discs to digital television broadcasts and video conferencing.; Audio file compressed using Speex compression and saved in the Ogg Vorbis container format; designed as an audio compression format specifically for speech; compresses voice at 2 to 44 kbps and supports 8 kHz, 16 kHz, and 32 kHz compression in the same bitstream.