我试过几个视频播放器，它们似乎都无法以正确的帧速率播放视频。速度非常慢，几乎停滞不前。
从命令行可以获得以下反馈：
MPlayer 1.3.0 (Debian), built with gcc-7 (C) 2000-2016 MPlayer Team
do_connect: could not connect to socket
connect: No such file or directory
Failed to open LIRC support. You will not be able to use your remote control.
Playing GH010031_reduced.mp4.
libavformat version 57.83.100 (external)
libavformat file format detected.
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x7f900dc762a0]Protocol name not provided, cannot determine if input is local or a network protocol, buffers and access patterns cannot be configured optimally without knowing the protocol
[lavf] stream 0: video (h264), -vid 0
[lavf] stream 1: audio (aac), -aid 0, -alang eng
VIDEO: [H264] 720x540 24bpp 59.940 fps 465.8 kbps (56.9 kbyte/s)
Failed to open VDPAU backend libvdpau_nvidia.so: cannot open shared object file: No such file or directory
[vdpau] Error when calling vdp_device_create_x11: 1
[VO_XV] It seems there is no Xvideo support for your video card available.
[VO_XV] Run 'xvinfo' to verify its Xv support and read
[VO_XV] DOCS/HTML/en/video.html#xv!
[VO_XV] See 'mplayer -vo help' for other (non-xv) video out drivers.
[VO_XV] Try -vo x11.
==========================================================================
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
libavcodec version 57.107.100 (external)
Selected video codec: [ffh264] vfm: ffmpeg (FFmpeg H.264)
==========================================================================
Clip info:
major_brand: isom
minor_version: 512
compatible_brands: isomiso2avc1mp41
encoder: Lavf58.20.100
Load subtitles in ./
==========================================================================
Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
AUDIO: 48000 Hz, 2 ch, floatle, 129.4 kbit/4.21% (ratio: 16172->384000)
Selected audio codec: [ffaac] afm: ffmpeg (FFmpeg AAC (MPEG-2/MPEG-4 Audio))
==========================================================================
AO: [pulse] 48000Hz 2ch floatle (4 bytes per sample)
Starting playback...
Movie-Aspect is 1.33:1 - prescaling to correct movie aspect.
VO: [x11] 720x540 => 720x540 Planar YV12
[swscaler @ 0x7f900e13e020]bicubic scaler, from yuv420p to bgra using MMXEXT
[swscaler @ 0x7f900e13e020]using unscaled yuv420p -> bgra special converter
A: 0.5 V: 0.6 A-V: -0.069 ct: 0.012 0/ 0 16% 16% 0.2% 0 0
运行xvinfo我得到：
X-Video Extension version 2.2
screen #0
no adaptors present
跑步mplayer -vo help
MPlayer 1.3.0 (Debian), built with gcc-7 (C) 2000-2016 MPlayer Team
Available video output drivers:
vdpau VDPAU with X11
xv X11/Xv
gl_nosw OpenGL no software rendering
x11 X11 ( XImage/Shm )
xover General X11 driver for overlay capable video output drivers
sdl SDL YUV/RGB/BGR renderer (SDL v1.1.7+ only!)
gl OpenGL
gl_tiled X11 (OpenGL) - multiple textures version
dga DGA ( Direct Graphic Access V2.0 )
fbdev Framebuffer Device
fbdev2 Framebuffer Device
matrixview MatrixView (OpenGL)
aa AAlib
caca libcaca
v4l2 V4L2 MPEG Video Decoder Output
directfb Direct Framebuffer Device
dfbmga DirectFB / Matrox G200/G400/G450/G550
xvidix X11 (VIDIX)
cvidix console VIDIX
null Null video output
xvmc XVideo Motion Compensation
mpegpes MPEG-PES to DVB card
yuv4mpeg yuv4mpeg output for mjpegtools
png PNG file
jpeg JPEG file
gif89a animated GIF output
tga Targa output
pnm PPM/PGM/PGMYUV file
md5sum md5sum of each frame
lspci显示：
00:00.0 Host bridge: Intel Corporation 440FX - 82441FX PMC [Natoma] (rev 02)
00:01.0 ISA bridge: Intel Corporation 82371SB PIIX3 ISA [Natoma/Triton II]
00:01.1 IDE interface: Intel Corporation 82371AB/EB/MB PIIX4 IDE (rev 01)
00:02.0 VGA compatible controller: InnoTek Systemberatung GmbH VirtualBox Graphics Adapter
00:03.0 Ethernet controller: Intel Corporation 82540EM Gigabit Ethernet Controller (rev 02)
00:04.0 System peripheral: InnoTek Systemberatung GmbH VirtualBox Guest Service
00:05.0 Multimedia audio controller: Intel Corporation 82801AA AC'97 Audio Controller (rev 01)
00:07.0 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 08)
00:0c.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller
00:0d.0 SATA controller: Intel Corporation 82801HM/HEM (ICH8M/ICH8M-E) SATA Controller [AHCI mode] (rev 02)