[MPlayer-users] VO: Description: Null video output

[Craig Jameson]

Success!!!



On Sat, 2022-03-26 at 07:49 -0400, The Wanderer wrote:
> On 2022-03-25 at 21:42, Craig Jameson wrote:
> 
> > In two separate blocks below, I have posted the outputs for
> > 
> > 	mplayer -vo help
> > and
> > 	mplayer -v Metallica\ -\ Nothing\ Else\ Matters.mp4
> > 
> > for the same user, but while running two different versions mplayer
> > under two different versions of RHEL.
> > 
> > 
> > The file .mplayer/config for this user contains a single line:
> > 
> > 	# Write your default config options here!
> 
> So it's effectively empty, as that line is a comment. That's useful
> mainly to confirm that, in the absence of command-line options to
> specify the VO, MPlayer is probably falling back on iterating through
> its compiled-in defaults.
> 
> > The version of   mplayer   that   works under RHEL 7 is 1.1-4.4.7
> > The version I am trying to get to work  under RHEL 8 is 1.5-8
> > 
> > The VO for the first version is reported to be Xv.
> > ./configure for the two versions was run with the following
> > options:
> > 
> > 1.1-4.4.7
> >  --enable-gui --codecsdir=/home/inatps/MPlayer/essential-2007100 --
> > prefix=/home/inatps/MPlayer/MPlayer2013 --yasm=
> > 
> > 1.5-8
> > --prefix=/home/inatps/MPlayer/MPlayer-1.5/local --
> > codecsdir=/home/inatps/MPlayer/MPlayer-1.5/essential-20071007
> > 
> > The permissions for the two installs are the same.
> > 
> > At first, I thought the problem was an operating system permissions
> > issue.  After some research, I thought is was a security issue with
> > ffmpeg.  Now, I am of the sense it is a compile-time issue.  I
> > remember
> > that there is a compile-time log.  Is that where I look
> > next?  Where do
> > I find it again?
> 
> The log you probably need is not the compile-time log, but the
> configure-time log. The configure step is where the detection of
> available features is performed, reported, and logged.
> 
> It should probably be in the same directory as './configure', from
> the
> two commands above, under the name 'config.log'.
> 
> > These two outputs of mplayer are from a binary compiled under RHEL
> > 6,
> > running under RHEL 7.
> > 
> > [Salomon]$ mplayer -vo help
> > MPlayer 1.1-4.4.7 (C) 2000-2012 MPlayer Team
> > Available video output drivers:
> >         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
> >         gl2     X11 (OpenGL) - multiple textures version
> >         fbdev   Framebuffer Device
> >         fbdev2  Framebuffer Device
> >         matrixview      MatrixView (OpenGL)
> >         v4l2    V4L2 MPEG Video Decoder Output
> >         xvidix  X11 (VIDIX)
> >         cvidix  console VIDIX
> >         null    Null video output
> >         mpegpes MPEG-PES to DVB card
> >         yuv4mpeg        yuv4mpeg output for mjpegtools
> >         png     PNG file
> >         jpeg    JPEG file
> >         tga     Targa output
> >         pnm     PPM/PGM/PGMYUV file
> >         md5sum  md5sum of each frame
> >         mng     MNG file
> > These two outputs of mplayer are from the fresh compile under RHEL
> > 8.5.
> > 
> > 
> > [Salomon]$ nmplayer -vo help
> > MPlayer 1.5-8 (C) 2000-2022 MPlayer Team
> > Available video output drivers:
> >         fbdev   Framebuffer Device
> >         fbdev2  Framebuffer Device
> >         v4l2    V4L2 MPEG Video Decoder Output
> >         cvidix  console VIDIX
> >         null    Null video output
> >         mpegpes MPEG-PES to DVB card
> >         yuv4mpeg        yuv4mpeg output for mjpegtools
> >         png     PNG file
> >         tga     Targa output
> >         pnm     PPM/PGM/PGMYUV file
> >         md5sum  md5sum of each frame
> 
> That seems to confirm that, yes, the problem is that support for
> other
> VO methods was not compiled in - which means that it was not detected
> at
> compile time. (In the second list, the listed VO methods other than
> the
> three which it tried are not actually for displaying the image, but
> for
> outputting to a file or for deciding not to output video after all.)
> 
> The most likely reason for this is that the correct development-
> header
> packages were not installed at that point. You'll probably need to
> identify which packages those are, get them installed, and re-compile
> MPlayer.
> 
> 
> What I usually do when I notice that a particular feature is detected
> as
> not available, at configure time, is to:
> 
> * Search config.log for the report about the detection of that
> feature,
>   to determine the correct name for the feature (as used internally
> by
>   the configure script). This step can sometimes be skipped.
> 
> * Search the configure script itself for the name of that feature, to
>   find the place where the detection for that feature occurs.
> 
> * Identify the name(s) of the header and/or library files that are
>   required for the detection to pass, based on the arguments that are
>   being passed to the compile-check statements in the configure
> script.
> 
> * For each such name, search the package repository for the path and
>   filename in question. (On Debian, I typically do this with 'apt-
> file
>   search'; what tool there may be for doing it on RHEL I do not
> know.)
> 
> * After identifying an appropriate package, install it, and run the
>   configure process again. (In some cases, there will not be any such
>   package; for those cases, either more complex solutions are needed,
> or
>   the feature simply is not available for the current environment.)
> 
> * If there are still features detected as unavailable which I think
>   should be available and want to include, repeat as necessary.
> 
> _______________________________________________
> MPlayer-users mailing list
> MPlayer-users at mplayerhq.hu
> https://lists.mplayerhq.hu/mailman/listinfo/mplayer-users