Does your phone or PC have a limited amount of storage space and do you want to clear as much junk as possible? No, I’m not talking about CCleaner but redundancy on your media files that aren’t compressed as much to their limit. However compressing your media is a balancing act between Compression <-> Quality as they are some methods to compress your photos, videos and even your files. Now I won’t go into too much about compression as 7-Zip has proven to be a successful and free open-source app to compress your data. If you are using Linux then you would use like Tarball archive, GNU Zip (gzip) and more, and you can find out more here:-

Now when it comes to having media like .mp3, .flac, .jpeg, .png, .mov, .mkv and more. There are two types of compressed media: lossy and lossless. Lossy compression downgrades or reduces media quality like ripping your CD audio tracks into MP3s at a bitrate 128kbps. But most DJs and audiophiles find MP3s at that bitrate not so appealing as well ruin the audio quality. You can get lossless compression like .flac but don’t have a higher compression ratio, in order to retain some of the precious audio waves and only focus on reducing the redundancy. Now they are some web-based or desktop-based apps that can reduce those media files’ size, and the ones I’m going to mention are HandBrake and HandBrake is a useful media compression tool, especially for streamers or video editors who had recorded videos on 4K camcorders or phones. The problem with recording ultra-high-definition videos at 60FPS, is the higher demand for storage space, because as you sussed already that UHD films require more data storage than 1080p30. With HandBrake, you can optimise and allow your video files (but not audio files) to be compressed as well as make it faster to upload on YouTube, Vimeo, DailyMotion etc. It is wise to make sure your videos are compressed as possible, especially since those video sites require a hell of a lot of cloud storage - as HandBrake offers Web Optimised option. If you like to know more about the magic of video compression, codecs and more, you can find out more here:-

As for audio files like your favourite songs or theme tunes, you could prefer to stream them from Amazon Music, Spotify, Deezer etc. Or you could rip them as .mpv .mp3 or .flac - depending on how much space you want to save for your MP3 player or phone, as those devices have limited storage compared to laptops and desktop PCs. So it depends on your CD Ripper app or Vinyl Ripper app on how you want your fave songs converted into digital media files.

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And as for your picture files, it depends on how your phone or camera takes snapshots based on how many megapixels are used to store all that data on your phone. As photos taken neat 108 megapixels can hog up your SD card or internal storage, as you may want to lower to say 1080p at 30 FPS and avoid 4K or 8K resolution at 60 FPS. However, if you are a professional photographer you would prefer to have your pictures of the best quality possible. You can have photo files stored as .jpeg which is more compressed and .png allows better quality and the ability to have a transparent background. With or any related media compressor apps, you could save between 15-70% of storage space, depending on how simple or complex the picture is - which is explained in that Video Compression link above. Give a shot but maybe backup your original photos in case the pictures look grainy or have like some compression artefacts.