You have one of those portable (digital) audio or video players, which can play MP3s, Ogg Vorbis or MPEG formats? You are looking for a Linux tool to (re)organize or convert the files on the player? Here are some generic Linux applications. For particular devices, see the Linux Compatibility Survey for Portable Audio and Video Players.
Mp3Splt-project(http://mp3splt.sourceforge.net/mp3splt_page/home.php) is an utility to split mp3 and ogg files selecting a begin and an end time position, without decoding. It's very useful to split large mp3/ogg to make smaller files or to split entire albums to obtain original tracks. If you want to split an album, you can select split points and filenames manually or you can get them automatically from CDDB (internet or a local file) or from .cue files. Supports also automatic silence split, that can be used also to adjust cddb/cue splitpoints.
FATSort(http://fatsort.berlios.de/) is a C utility that sorts FAT16 and FAT32 partitions. It even can handle long file name entries. It was developed to sort my MP3 files on a MP3 hardware player.
Floola(http://www.floola.com/modules/wiwimod/) is an application to efficiently manage your iPod or your Motorola mobile phone (any model that supports iTunes) under Linux, Mac OS X, and Windows. Video and music files can be easily added and removed. Playlists can be managed with simple drag-and-drop. Lyrics and artwork are supported. Tracks can be submitted to last.fm.
Cactus(http://cactus.hey-you-freaks.de/) is an audio player. It shows all your music files in a kind of database, and you can easily browse, edit, and search your collection. It also supports synchronizing your music collection with a mobile player device. It plays MP3, WAV, and Ogg. It can also import and rip audio CDs, automatically show album covers, tag MP3 files, and maintain a fast library.
autoSyncPodder(http://robert.penz.name/autosyncpodder/) is a program which automatically downloads podcasts and syncs them with your MP3/Ogg player without user interaction. The download part of the autoSyncPodder is called by cron once a day. The syncing is started as soon as the player is plugged into a USB port. If a file gets deleted on the player, the file will get deleted at the next sync on the computer too.
EasyPMP(http://pmplib.sourceforge.net/) is a program used to create and maintain the music database on a variety of portable music players. This allows tracks to be browsed by artist, album, genre, etc., rather than by directory structure. The following devices are supported: iRiver H100 series; iRiver H300 series; iRiver H10 UMS; iRiver H10 MTP (with emergency connect mode); iRiver H10Jr. UMS; iRiver U10 UMS; MEDION MDJuke220 and MDJuke 440; and Samsung YH-820, YH-920, and YH-925. It is developed as part of a project called PMPlib, which aims to develop a library that can be used by desktop media players and other programs, in order to support these devices.
cpShuffleSature(http://makarevitch.org/cpShuffleSature/) randomly copies files from one directory to another, and stops only when the target filesystem is full. It is designed for copying music, pictures, or films onto portable hardware devices which serve as a filesystem (such as I-Bead, iPod, or Archos). The files are selected accross subdirectories which are replicated on the target. If necessary, cpShuffleSature filters out parts of the original directory names and also leaves a given amount of available space on the target filesystem.
tsheadphone(http://www.johncon.com/john/SSheadphoneAmp/) implements a spatial distortion reduction scheme that allows a RIFF or WAVE format selection from a music CD to be "digitally re-mastered" for use with headphones. It works especially well with portable high capacity CD or MP3 players.
ReOrganize4L(http://reorganize4l.sourceforge.net/) is a tool for rearranging the files on an MP3 stick. It is based on ReOrganize! for MS-Windows and supports many devices. The main idea behind it is that most MP3 sticks sort the tracks by date. ReOrganize4L first copies the tracks to a temporary directory on your hard drive, then rearranges the order of the files. After this, it copies the tracks (with the new order) back to the stick.
You have one of those USB sticks which can play MP3s and you are looking for a convenient way to (re)organize files on the player? Or you want something similar to reOrganize running on Linux and available in source? Then grab this mp3man.tk(http://www.robf.de/Hacking/tcltk/index.html) Tk-script. It makes mounting, coping, deleting, reorganizing and unmounting the player a fun.
MP3 Database(http://mp3db.sourceforge.net/) is a database for MP3s stored on removable media. It can also support other media using plugins.
Stickloader(http://stickloader.berlios.de/) is an easy Java-based solution for copying music files from your hard disk to your USB stick and re-encoding them at a lower bitrate for more efficient usage of your MP3 player disk space. MP3 files and whole directories can be easily dragged on the Stickloader window (which always stays on top) and they are automatically re-encoded using LAME and copied to your USB stick by using a temporary directory to avoid blocking the encoding process.
mp3togo(http://puddle.ca/mp3togo/) loads MP3, Ogg Vorbis, FLAC, and WAV files on to a portable MP3 player by decoding them (if required) and reencoding in a consistent lower bitrate MP3 (or Vorbis) format. The idea is to take music from a library of diverse archival quality encodings and convert it to a space efficient format playable on a portable device. mp3togo will run as a stand alone program, or can be imported as python modules to use its components in another program.
AudConvert(http://www.linuxhardware.org/article.pl?sid=06/02/08/042226) is an application that is designed to take any audio format and convert it to any other audio format. It was created to convert a collection of Ogg Vorbis files into MP3s for use on portable devices.
Here is a audio file conversion HOWTO.
ipod-encoder(http://sourceforge.net/projects/ipod-encoder/) is a command line tool for convenient encoding of video files for use on iPod video. It uses the ffmpeg tool for the actual encoding. It features recursive encoding of all files in a directory, and generating a podcast.xml file for convenient use in iTunes. It can be used in a cron job that periodically checks directories for new files and encodes them without user intervention.
TivoPod(http://sourceforge.net/projects/tivopod) is a transcoding and podcasting agent that extracts content from the TiVo "Now Playing" list and serves it up as a video podcast for iPods, PSPs, and other portable media devices.