Re: [LAD] [LAA] gst123-0.1.2

Thanks for your help and response...

FYI, here's a few bug reports/feature-missing things:

(1) I finally figured out those flashing squares that appear every
time gst123 changes songs. It's album-art images, displayed in an X
window! These need to stay up longer, as only by forcing the audio
device to be busy and playing back a giant directory of files, I was
able to actually see that these are windows containing images, and not
some weird new display-glitching bug caused by KDE's "Smooth Tasks"
widget. To be useful, the display of the image needs to be held for a
certain amount of time after you're sure the window-system has
actually rendered the image. Perhaps a single integer option
--albumart-time -- when set to 0 image display is suppressed,
otherwise, an integer like 1000 which would hold the album-art image
for 1 second.

(And yes, I realize that a fix for this issue is easily had in my
script "play-cd" (shorthand for play sound only @ 44.1, vs "play-tv"
w/ X/Video @ 48k):
| #!/bin/sh
| args="`/bin/ls -d $*`"
| export DISPLAY=''
| exec gst123 -a alsa=mythcd $args
)

(2) Sometimes video windows come up at the wrong size (tiny). You can
resize them with the window manager and resize it back and get the
correct aspect. Or you can quit and run it again and find it sized
correctly.

(3) Is there a way to create a specific, stable, window-name for the
video window created, perhaps settable as commandline parameter. That
way for captions, you don't really need to worry about "overwriting"
the video with transparent letters like you would on an actual TV
caption. Instead, wrap your program in an external program such as
Python, or WINTERP (*) that "captures" the video window (much like a
window manager would, or how "mplayer" windows are displayed insider
wrappers like smplayer kmplayer etc) and parses the time-data-stream
information continuously output by gst123. Below the video window you
stick a text widget and display caption text independently of the
video. There's really no need to overlay and worry about transparency
mapping through letters and slowing down the rendering, and all that
potential, hardware-dependent fail. Stick the text in a GUI toolkit
where all the region and language issues can be handled
appropriately... Such tools are happy to update a few times a second
to display new captions while X is off rendering the video (or
stepping out of the way) in the most efficient, platform-independent
manner available.

Niels
http://nielsmayer.com

PS: (*) I just got my old dead opensource project
http://nielsmayer.com/winterp/ (
ftp://ftp.x.org/contrib/devel_tools/winterp.lsm ) 99%fully
running/ported to the latest Linux/Gcc/X courtesy of PlanetCCRMA
having the following packages
openmotif-2.3.2-5.1.svn.fc12.ccrma.x86_64
openmotif-devel-2.3.2-5.1.svn.fc12.ccrma.x86_64 ... one of the nice
things it provides (and I'm happy i'll no longer need to supply my own
version-of) is expect-5.43.0-19.fc12.x86_64 -- a portable way to talk
to existing tty-based programs as if they were running it a terminal.
Except they're not actually running in a terminal, they're being
controlled by a GUI. Probably nothing more than anybody does with
Python, or Java, or Ruby, or Perl, or ... these days ... however, for
line-based, or s-expression-based results (e.g. multiple lisp or
scheme-based systems talking to each other) the asynchronous
subprocess facility WINTERP provides is potentially more elegant for
the application writer comfortable with putting parentheses before the
functor.

Anyways, w/o taking up much of my time, I want to put it up on
sourceforge, salvage the interesting parts, and see what happens -- at
this point as yet another "background" task/distraction. However
running code speaks, and this is running code. I'm just happy to have
some simple winterp-based utilities back and running again: win-grep (
http://nielsmayer.com/winterp/scrnsnaps/grep-br.gif ) and win-dircmp (
http://nielsmayer.com/winterp/scrnsnaps/dircmp.gif ). And for doing
music/midi stuff, the XmGraph widget can't be beat: it's quite awesome
in interactive mode, as well as its intelligent graph layout:
http://nielsmayer.com/winterp/scrnsnaps/graphcalc.gif
http://nielsmayer.com/winterp/scrnsnaps/grph-whier.gif (
http://nielsmayer.com/winterp/examples/grph-whier.lsp )
http://nielsmayer.com/wwweasel/node24.htm ). ANd lets not forget
WINTERP's path-based-"animation" facilities to make arbitrary
interactive controllers and displays (beyond what a prebuilt "widget'
might provide) that move smoothly with built-in double-buffering:
http://nielsmayer.com/winterp/scrnsnaps/xtango/hanoi.gif
http://nielsmayer.com/winterp/scrnsnaps/xtango/test-dial.gif
http://nielsmayer.com/winterp/scrnsnaps/xtango/test-gauge.gif
http://nielsmayer.com/winterp/scrnsnaps/xtango/test-knob.gif ...

FYI, this is all it takes to talk to an asynchronous subprocess --
such as running&controlling gst123 ...
http://nielsmayer.com/winterp/examples/subcalc.lsp (simple UI to run
"bc" as an asynchronous subprocess, to perform, for example, infinite
precision and size arithmetic as a "background process"):
  (setq subproc-pty (exp_spawn "bc" "bc")) ;create subprocess, the
bc(1) calculator
  (setq subproc-pid (exp_get_pid))
  (setq input-cb
        (xt_add_input ;XtAppAddInput()
         subproc-pty :READ_LINE_TO_STRING
         '(;; READ_LINE_TO_STRING fires callback once per line, binding line
to FDINPUTCB_STRING
           (send list-w :add_item FDINPUTCB_STRING 0) ;XmListAddItem()
           (send list-w :set_bottom_pos 0) ;XmListSetBottomPos()
           )
         ))
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Received on Thu Jul 8 00:15:06 2010