To ensure that all authers is known for each medie file. Only files that cannot include authers in the source are mentioned. 

Most graphics are by Iwan Gabovitch aka qubodup.

All of qubodup's graphics are in the Public domain
Data from the OpenArena team is under GPL v2
Data from the Dietrich Radel (originally part of Trackballs) is under GPL v2
Poul Sander's files are multi licensed under "GPL v2 or later" OR "CC-BY-SA any version"

Misc:
blockAttack.ico         Poul Sander

/fonts/
freeserif.ttf           Free Software Foundation
penguinattack.ttf       Dustin Norlander - GPLv2

/textures/
alt_gfx/back_board_sample_snow.jpg  Poul Sander
alt_gfx/background.png  Poul Sander
alt_gfx/board_back_back_mirror.png  qubodup (mirror of board_back_back.pn)
back_board.png          qubodup
background.png          qubodup
background_sixteen_nine.png  Poul Sander (based of qubodup's background.png)
ball_blue.png           qubodup
ball_gray.png           qubodup
ball_green.png          qubodup
ball_purple.png         qubodup
ball_red.png            qubodup
ball_turkish.png        qubodup
ball_yellow.png         qubodup
b_blank.png             Poul Sander
b_exit.png              qubodup
b_highscore.png         qubodup
black_back_ground.png   Poul Sander
black_line.png          Poul Sander
blue.png                qubodup
board_back_back.png     qubodup
bomb.png                Poul Sander
chain_frame.png         Poul Sander
counter_1.png           Poul Sander
counter_2.png           Poul Sander
counter_3.png           Poul Sander
crossover.png           Poul Sander
cursor.png              Poul Sander
explosion0.png          openarena-svn887:/textures/sfx/130boom
explosion1.png          openarena-svn887:/textures/sfx/130boom
explosion2.png          openarena-svn887:/textures/sfx/130boom
explosion3.png          openarena-svn887:/textures/sfx/130boom
fallback.png            Poul Sander
garbage_bl.png          qubodup
garbage_b.png           qubodup
garbage_br.png          qubodup
garbage_fill.png        qubodup
garbage_gml.png         qubodup
garbage_gm.png          qubodup
garbage_gmr.png         qubodup
garbage_l.png           qubodup
garbage_ml.png          qubodup
garbage_m.png           qubodup
garbage_mr.png          qubodup
garbage_r.png           qubodup
garbage_tl.png          qubodup
garbage_t.png           qubodup
garbage_tr.png          qubodup
green.png               qubodup
grey.png                qubodup
gui_back_white.png      Derived from UI pack by Kenney Vleugels (www.kenney.nl) (CC0 license)
gui_back_yellow.png     Derived from UI pack by Kenney Vleugels (www.kenney.nl) (CC0 license)
help_controller.png     nicefrog (https://opengameart.org/content/generic-gamepad-template)
i_check_box_area.png    Poul Sander
icon.png                Poul Sander
i_draw.png              Poul Sander
i_game_over.png         Poul Sander
i_level_check_box_marked.png    Poul Sander
i_level_check_box.png   Poul Sander
i_level_check.png       Poul Sander
i_loser.png             Poul Sander
i_stage_clear_limit.png Poul Sander
i_winner.png            Poul Sander
menu_marked.png         Derived from UI pack by Kenney Vleugels (www.kenney.nl) (CC0 license)
menu_unmarked.png       Derived from UI pack by Kenney Vleugels (www.kenney.nl) (CC0 license)
mouse.png               Poul Sander
purple.png              qubodup
ready.png               Poul Sander
red.png                 qubodup
smileys0.png            qubodup
smileys1.png            qubodup
smileys2.png            qubodup
smileys3.png            qubodup
trans_cover.png         Poul Sander
turkish.png             qubodup
yellow.png              qubodup

/sound/
pop.ogg                 openarena-svn887:/sound/weapons/rocket/rockf1a.wav
cameraclick.ogg         openarean-svn887:/sound/misc/w_pkup.wav
typing.ogg              openarena-svn887:/sound/world/clack.wav
counter.ogg             openarena-svn900:/sound/feedback/hitlo.wav
counter_final.ogg       openarena-svn900:/sound/feedback/hit.wav
applause.ogg            (CC-BY 3.0) Blender Foundation - Cut by LeeZH (http://opengameart.org/content/applause)

/music/
bgmusic.ogg             "Life by Design", by Dietrich Radel (GPL)
highbeat.ogg            derived from "Genesis (In The Beginning)", by Dietrich Radel (GPL)