MPlayer
Quick cheatsheet for MPlayer. Most of the options are identical in MPV too, which is the program I currently use.
-afm dmo= Sometimes useful to reproduce files with out of sync audio-ss HH:MM:SS= Start playing at HH:MM:SS-frames n= Stop playing afternframes-vc null -vo null -ao pcm:fast:waveheader:file=$file= Convert an audio file to a wavmplayer video -vf cropdetect= Try to detect the areas of video to cropmplayer video -vo jpeg:outdir=dir/ -nosound= Write every frame of video as a jpeg image in outdirmplayer video -vo gif89a:output=filedioutput.gif:fps=5 -nosound= Make an animated gif from a video (usually in very low quality)mplayer video -vo xvmc:bobdint:queue -vc ffmpeg12mc= To make use of the hardware acceleration of the XvMC protocol-sub subtitles= Load subtitles (generally it’s a.srtfile)-loop n= Loop a videontimes (use 0 to loop forever)-nosound -vo x11 -zoom -rootwin -loop 0 video= Options needed to use a video as desktop background. Other video outputs can work too as long as they support zooming-vf delogo=x:y:w:h:-1= Remove a logo from a video.xandyare coordinates from the top left corner of the video,wandhare width and height of the logo to be removed and-1highlights the border of the are so to find where the filter is working more easily (clearly to be removed in the final output)~/.mplayer/subfont.ttf= Symbolic link to a TrueType font to use for subtitles-vf screenshot= Enable taking screenshots. Withssave current frame, withShift+sstarts saving every frame to a file untilShift+sis pressed again-af volume=30:1:0= Increases or lowers the volume beyond the sound card limits. Here 30 means 30dB more than the limit. 1 enables soft clipping to reduce distorsions. Volume ranges from -200 to 60 (dB), where 0 is clearly the default-dumpfile file -dumpstream url= Save url to file