Contrary to the mplayer documentation, the gl video output driver may
work better than xv, at least for some systems, in at least two ways.

Playing a large video (1080p), xv can't keep up, and the video falls
behind audio.  With gl, works great.  Even with xv, CPU is
considerably less than 100%, so the problem is "elsewhere".

Playing any video, it looks like xv attempts to sync to 60 fps, but my
internal display is 50 Hz.  Video looks fine on an external display
(60 Hz), but there's a lot of tearing on the LCD.  Video is smooth on
either display using gl output.

This is a laptop with intel video, other systems may be different, but
if you're having any trouble with mplayer video, the gl driver is
worth trying.

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I used to notice a lot of tearing on Intel X3100 chipsets (GM965).  I
don't see any issues anymore, but maybe someone will find this useful
anyway.

Another tip is to check the output of xvinfo.  For example, on a
ThinkPad X61s, xvinfo gives the following results.

  X-Video Extension version 2.2
  screen #0
    Adaptor #0: "Intel(R) Textured Video"
      number of ports: 16
      port base: 86
      operations supported: PutImage 
      supported visuals:
	depth 24, visualID 0x21
      number of attributes: 3
	"XV_BRIGHTNESS" (range -128 to 127)
		client settable attribute
		client gettable attribute (current value is 0)
	"XV_CONTRAST" (range 0 to 255)
		client settable attribute
		client gettable attribute (current value is 0)
	"XV_SYNC_TO_VBLANK" (range -1 to 1)
		client settable attribute
		client gettable attribute (current value is 1)
      maximum XvImage size: 2048 x 2048
      Number of image formats: 5
	id: 0x32595559 (YUY2)
	  guid: 59555932-0000-0010-8000-00aa00389b71
	  bits per pixel: 16
	  number of planes: 1
	  type: YUV (packed)
	id: 0x32315659 (YV12)
	  guid: 59563132-0000-0010-8000-00aa00389b71
	  bits per pixel: 12
	  number of planes: 3
	  type: YUV (planar)
	id: 0x30323449 (I420)
	  guid: 49343230-0000-0010-8000-00aa00389b71
	  bits per pixel: 12
	  number of planes: 3
	  type: YUV (planar)
	id: 0x59565955 (UYVY)
	  guid: 55595659-0000-0010-8000-00aa00389b71
	  bits per pixel: 16
	  number of planes: 1
	  type: YUV (packed)
	id: 0x434d5658 (XVMC)
	  guid: 58564d43-0000-0010-8000-00aa00389b71
	  bits per pixel: 12
	  number of planes: 3
	  type: YUV (planar)
    Adaptor #1: "Intel(R) Video Overlay"
      number of ports: 1
      port base: 102
      operations supported: PutImage 
      supported visuals:
	depth 24, visualID 0x21
      number of attributes: 11
	"XV_COLORKEY" (range 0 to 16777215)
		client settable attribute
		client gettable attribute (current value is 66046)
	"XV_BRIGHTNESS" (range -128 to 127)
		client ...
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On Fri, 24 Dec 2010 22:46:36 -0500

What is your hardware setup for this?

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Thinkpad x200s.  1.8Ghz Core 2, Intel GM45 or X4500 or whatever they
called it that week.  My screen is only 1440x900, so I generally aim
for 720p videos to save time, but I have some 1080p videos from before
I learned to control youtube-dl properly. :)

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On Sun, 26 Dec 2010 23:54:24 -0500

That's incredible. I was reading some threads(albeit from some Linux
distro mailing list) from 2008 about a 2Ghz Core2Duo with some Intel
GPU on a R61(a machine I recently bought) being too slow for 1080
resolutions with mplayer in any situation.

This gives me some hope that I don't need to down-convert media to
720p... What codecs and containers are you using, and what bitrate?

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Well, we all know linux is unusable as a desktop operating system. :)
Exact performance probably depends on screen resolution too, I'm
downscaling, but the R61 if I'm not mistaken may have a bigger screen.
 The files I was playing with were mp4, maybe around 5 mbit?

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