[pitivi] render: Properly filter possible encoder restriction fields

[Thibault Saunier <tsaunier src gnome org>]

commit c35816e8404bc8aa47f0014d527679a7bae9751e
Author: Thibault Saunier <tsaunier gnome org>
Date:   Wed Dec 14 15:31:51 2016 -0300

    render: Properly filter possible encoder restriction fields
    
    Otherwise we might end up tring to render in an format, for
    example opusenc is not able to handle all the formats
    we expose to the user.
    
    Fixes T7642
    
    Reviewed-by: Alex Băluț <alexandru balut gmail com>
    Differential Revision: https://phabricator.freedesktop.org/D1555

 pitivi/render.py |   55 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 55 insertions(+), 0 deletions(-)
---
diff --git a/pitivi/render.py b/pitivi/render.py
index 4ae2c24..ad819b2 100644
--- a/pitivi/render.py
+++ b/pitivi/render.py
@@ -700,6 +700,59 @@ class RenderDialog(Loggable):
             name = basename
         self.fileentry.set_text(name)
 
+    def _update_valid_restriction_values(self, caps, combo, caps_template,
+                               model, value,
+                               caps_template_expander=None):
+        def caps_template_expander_func(caps_template, value):
+            return caps_template % value
+
+        if not caps_template_expander:
+            caps_template_expander = caps_template_expander_func
+
+        model_headers = [model.get_column_type(i) for i in range(model.get_n_columns())]
+        reduced_model = Gtk.ListStore(*model_headers)
+        for name, value in dict(model).items():
+            ecaps = Gst.Caps(caps_template_expander(caps_template, value))
+            if not caps.intersect(ecaps).is_empty():
+                reduced_model.append((name, value))
+
+        combo.set_model(reduced_model)
+
+        set_combo_value(combo, value)
+        if get_combo_value(combo) != value:
+            combo.set_active(len(reduced_model) - 1)
+            self.warning("%s in %s not supported, setting: %s",
+                value, caps_template, get_combo_value(combo))
+
+    def _update_valid_audio_restrictions(self, factory):
+        template = [t for t in factory.get_static_pad_templates()
+                    if t.direction == Gst.PadDirection.SINK][0]
+
+        caps = template.static_caps.get()
+        self._update_valid_restriction_values(caps, self.sample_rate_combo,
+                                              "audio/x-raw,rate=(int)%d",
+                                              audio_rates,
+                                              self.project.audiorate)
+
+        self._update_valid_restriction_values(caps, self.channels_combo,
+                                              "audio/x-raw,channels=(int)%d",
+                                              audio_channels,
+                                              self.project.audiochannels)
+
+    def _update_valid_video_restrictions(self, factory):
+        def fraction_expander_func(caps_template, value):
+            return caps_template % (value.num, value.denom)
+
+        template = [t for t in factory.get_static_pad_templates()
+                    if t.direction == Gst.PadDirection.SINK][0]
+
+        caps = template.static_caps.get()
+        self._update_valid_restriction_values(
+            caps, self.frame_rate_combo,
+            "video/x-raw,framerate=(GstFraction)%d/%d", frame_rates,
+            self.project.framerate,
+            caps_template_expander=fraction_expander_func)
+
     def updateAvailableEncoders(self):
         """Updates the encoder comboboxes to show the available encoders."""
         self.muxer_combo_changing = True
@@ -1105,6 +1158,7 @@ class RenderDialog(Loggable):
             # The user directly changed the video encoder combo.
             self.debug("User chose a video encoder: %s", name)
             self.preferred_vencoder = name
+        self._update_valid_video_restrictions(factory)
 
     def _videoSettingsButtonClickedCb(self, unused_button):
         factory = get_combo_value(self.video_encoder_combo)
@@ -1124,6 +1178,7 @@ class RenderDialog(Loggable):
             # The user directly changed the audio encoder combo.
             self.debug("User chose an audio encoder: %s", name)
             self.preferred_aencoder = name
+        self._update_valid_audio_restrictions(factory)
 
     def _audioSettingsButtonClickedCb(self, unused_button):
         factory = get_combo_value(self.audio_encoder_combo)