some image and audio formats (especially older ones) are like that, yes. others use compression or other techniques to suit their need. like a sound can be a raw recording sample. or a sound can be described with Attack/Decay/Sustain/Release, along with octave and note etc. so a MIDI file is an audio file format without samples.
i once created an image format to be used for spiraling out images, instead of pixel arrays they were concentric circles of pixels that i could easily offset.
the answer to your how question is as needed.
some image and audio formats (especially older ones) are like that, yes. others use compression or other techniques to suit their need. like a sound can be a raw recording sample. or a sound can be described with Attack/Decay/Sustain/Release, along with octave and note etc. so a MIDI file is an audio file format without samples.
i once created an image format to be used for spiraling out images, instead of pixel arrays they were concentric circles of pixels that i could easily offset.