gstreamer/examples/pipeline-tester

#!/usr/bin/env python
#
# gst-python
# Copyright (C) 2005 Andy Wingo <wingo@pobox.com>
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Library General Public
# License as published by the Free Software Foundation; either
# version 2 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Library General Public License for more details.
#
# You should have received a copy of the GNU Library General Public
# License along with this library; if not, write to the
# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA.


# A test more of gst-plugins than of gst-python.


import sys

import pygtk
pygtk.require('2.0')
import gtk
import gtk.gdk
import pango

import pygst
pygst.require('0.9')
import gst


data = (('Video capture via V4L',
         'v4lsrc name=source \n'
         '    ! video/x-raw-yuv,format=(fourcc)I420 \n'
         '    ! videorate \n'
         '    ! xvimagesink'),
        ('Sound capture via ALSA',
         'alsasrc\n'
         '    ! audio/x-raw-int,rate=22050,depth=16,channels=1,width=16,signed=(boolean)TRUE,endianness=1234\n'
         '    ! level signal=true\n'
         '    ! alsasink'))


def escape(s, chars, escaper='\\'):
    for c in chars:
        s = s.replace(c, '%s%s' % (escaper, c))
    return s


def make_model():
    m = gtk.ListStore(str, str)
    for pair in data:
        i = m.append()
        m.set_value(i, 0, pair[0])
        m.set_value(i, 1, pair[1])
    return m


class Window(gtk.Window):
    def __init__(self):
        gtk.Window.__init__(self, gtk.WINDOW_TOPLEVEL)
        self.playing = False
        self.selected_pipe = None
        self.pipeline = None
        self.prepare_ui()

    def prepare_ui(self):
        self.set_default_size(300,400)
        self.set_title('GStreamer Pipeline Tester')
        self.set_type_hint(gtk.gdk.WINDOW_TYPE_HINT_DIALOG)
        self.connect('delete-event', lambda *x: gtk.main_quit())
        self.set_border_width(18)
        b = gtk.VBox(False, 12)
        b.show()
        self.add(b)
        l = gtk.Label()
        l.set_markup('<big><b>GStreamer Pipeline Tester</b></big>')
        l.show()
        b.pack_start(l, False, False, 6)
        l = gtk.Label('Choose a pipeline below to run.')
        l.show()
        b.pack_start(l, False, False, 0)
        sw = gtk.ScrolledWindow()
        sw.set_policy(gtk.POLICY_NEVER, gtk.POLICY_NEVER)
        sw.set_shadow_type(gtk.SHADOW_IN)
        sw.show()
        b.pack_start(sw, True, True, 6)
        tv = gtk.TreeView(make_model())
        r = gtk.CellRendererText()
        r.set_property('xalign', 0.5)
        c = gtk.TreeViewColumn('System', r, text=0)
        tv.append_column(c)
        tv.set_headers_visible(False)
        tv.show()
        sw.add(tv)
        l = gtk.Label()
        l.set_selectable(True)
        l.show()
        b.pack_start(l, False, False, 0)
        bb = gtk.HButtonBox()
        bb.set_layout(gtk.BUTTONBOX_SPREAD)
        bb.show()
        b.pack_start(bb, False, False, 0)
        bu = gtk.Button(stock=gtk.STOCK_MEDIA_PLAY)
        bu.set_focus_on_click(False)
        bu.show()
        bb.pack_start(bu, True, False, 0)

        def on_changed(s):
            m, i = s.get_selected()
            if m:
                self.selected_pipe = m.get_value(i, 1)
                pasteable = escape(self.selected_pipe, '\n)(')
                l.set_markup('<small><tt>%s</tt></small>' % pasteable)
            else:
                self.selected_pipe = None
                l.set_markup('')
        tv.get_selection().connect('changed', on_changed)

        bu.connect('clicked', self.play_toggled)

    def play(self):
        pipestr = self.selected_pipe
        pipeline = gst.parse_launch(pipestr)
        if pipeline.set_state(gst.STATE_PLAYING) != gst.STATE_SUCCESS:
            print 'state change failed'
            return False
        else:
            self.pipeline = pipeline
            return True

    def stop(self):
        self.pipeline.set_state(gst.STATE_NULL)
        self.pipeline = None

    def play_toggled(self, button):
        if self.playing:
            self.stop()
            button.set_label(gtk.STOCK_MEDIA_PLAY)
            self.playing = False
        else:
            if self.play():
                self.playing = True
                button.set_label(gtk.STOCK_MEDIA_STOP)

if __name__ == '__main__':
    w = Window()
    w.show()
    gtk.main()