rework filter chain to embed processes and inputs

src/overlay/filters.py

@@ -1,3 +1,6 @@
+import threading
+
+
 def filter_escape(s):
     return (str(s)
         .replace(':', '\\:')
@@ -5,12 +8,27 @@ def filter_escape(s):
         .replace(';', '\\;')
     )
 
+class FFmpegInput:
+    def __init__(self, name, **options):
+        self.name = name
+        self.options = options
+
+    def format(self):
+        args = []
+        for (k, v) in self.options.items():
+            args.append('-' + k)
+            if v is not None:
+                args.append(str(v))
+        args.append('-i')
+        args.append(self.name)
+        return args
+
 class FFmpegFilter:
-    def __init__(self, name, *, ins=[], outs=[], **args):
+    def __init__(self, name, *, ins=None, outs=None, **args):
         self.name = name
         self.args = args
-        self.ins = ins
-        self.outs = outs
+        self.ins = ins or []
+        self.outs = outs or []
 
     def __repr__(self):
         return '{}({}, {}, ins={!r}, outs={!r})'.format(
@@ -31,8 +49,10 @@ class FFmpegFilter:
         )
 
 class FFmpegChain:
-    def __init__(self, *filters):
+    def __init__(self, *filters, inputs=None, runners=None):
         self.filters = list(filters)
+        self.inputs = inputs or []
+        self.runners = runners or []
 
     def append(self, f):
         self.filters.append(f)
@@ -51,9 +71,20 @@ class FFmpegChain:
     def __repr__(self):
         return '{}({})'.format(self.__class__.__name__, ', '.join(repr(f) for f in self.filters))
 
-    def __str__(self):
+    def format_inputs(self):
+        args = []
+        for input in self.inputs:
+            args.extend(input.format())
+        return args
+
+    def format_filters(self):
         return ', '.join(str(f) for f in self.filters)
 
+    def run(self):
+        for r in self.runners:
+            t = threading.Thread(target=r, daemon=True)
+            t.start()
+
 class FFmpegGraph:
     def __init__(self, *chains):
         self.chains = list(chains)
@@ -75,5 +106,20 @@ class FFmpegGraph:
     def __repr__(self):
         return '{}({})'.format(self.__class__.__name__, ', '.join(repr(c) for c in self.chains))
 
-    def __str__(self):
-        return '; '.join(str(c) for c in self.chains)
+    def format(self):
+        args = []
+
+        in_no = 0
+        for c in self.chains:
+            args.extend(c.format_inputs())
+            for i in range(len(c.inputs)):
+                c.filters[0].ins.append(str(in_no))
+                in_no += 1
+
+        args.append('-filter_complex')
+        args.append('; '.join(c.format_filters() for c in self.chains))
+        return args
+
+    def run(self):
+        for c in self.chains:
+            c.run()

src/overlay/obs/base.py

@@ -53,8 +53,8 @@ class OBSScene:
 
     def to_ffmpeg(self, scene=None):
         scene = scene or self.current_scene
-        runners, chains = self.sources[scene].to_ffmpeg(self)
+        chains = self.sources[scene].to_ffmpeg(self)
 
         r = FFmpegGraph()
         r.extend(chains)
-        return runners, r
+        return r

src/overlay/obs/browser.py

@@ -65,6 +65,7 @@ class OBSBrowserSource(OBSSource):
         fifo_path = os.path.join(self.tempdir, 'frame.bin')
         fifo = os.mkfifo(fifo_path)
         runner = functools.partial(capture_page, url=self.url, outfile=fifo_path, dims=(self.width, self.height))
-        return [runner], [FFmpegChain(
-            FFmpegFilter('movie', filename=fifo_path, loop=0)
+        return [FFmpegChain(
+            inputs=[FFmpegInput(fifo_path, f='image2pipe', framerate=runner.rate, follow=1, probesize=8192)],
+            runners=[runner]
         )]

src/overlay/obs/scene.py

@@ -28,18 +28,17 @@ class OBSSceneSource(OBSSource):
 
     def to_ffmpeg(self, scene):
         prefix = identifiery(self.name)
-        i = 1
+        i = 0
         graph = [FFmpegChain(
-            FFmpegFilter('color', c='black', s='{}x{}'.format(*scene.dimensions), outs=[prefix + str(i)])
+            FFmpegFilter('color', c='black', s='{}x{}'.format(*scene.dimensions), outs=[prefix + str(0)])
         )]
-        runners = []
+        i += 1
 
         for item in self.items:
             if not item['visible']:
                 continue
 
-            rs, chains = scene.sources[item['name']].to_ffmpeg(scene)
-            runners.extend(rs)
+            chains = scene.sources[item['name']].to_ffmpeg(scene)
             c = chains[-1]
 
             if item['scale']['x'] != 1.0 or item['scale']['y'] != 1.0:
@@ -58,15 +57,19 @@ class OBSSceneSource(OBSSource):
                 c.append(FFmpegFilter('rotate',
                     angle=deg2rad(item['rot'])
                 ))
-            c.append(FFmpegFilter('overlay',
-                eval='init',
-                x=item['pos']['x'],
-                y=item['pos']['y'],
-                ins=[prefix + str(i)],
-                outs=[prefix + str(i + 1)])
-            )
+            if not c[-1].outs:
+                c[-1].outs.append(prefix + 'Out' + str(i))
+            chains.append(FFmpegChain(
+                FFmpegFilter('overlay',
+                    eval='init',
+                    x=item['pos']['x'],
+                    y=item['pos']['y'],
+                    ins=[prefix + str(i - 1), c[-1].outs[-1]],
+                    outs=[prefix + str(i)]
+                )
+            ))
             i += 1
 
             graph.extend(chains)
 
-        return runners, graph
+        return graph

src/overlay/obs/text.py

@@ -13,7 +13,7 @@ class TextSource(OBSSource):
         self.shadow_color = '#000000'
 
     def to_ffmpeg(self, scene):
-        return [], [FFmpegChain(
+        return [FFmpegChain(
             FFmpegFilter('drawtext',
                 expansion='none',
                 fontcolor=self.color,

src/overlay/obs/video.py

@@ -1,4 +1,4 @@
-from ..filters import FFmpegChain, FFmpegFilter
+from ..filters import FFmpegInput, FFmpegChain, FFmpegFilter
 from .base import OBSSource
 
 
@@ -12,9 +12,7 @@ class ImageSource(OBSSource):
         self.infile = data['settings']['file']
 
     def to_ffmpeg(self, scene):
-        return [], [FFmpegChain(
-            FFmpegFilter('movie',  filename=self.infile)
-        )]
+        return [FFmpegChain(inputs=[FFmpegInput(self.infile)])]
 
 @OBSSource.type('ffmpeg_source')
 class FFmpegSource(OBSSource):
@@ -28,7 +26,7 @@ class FFmpegSource(OBSSource):
         self.loop = data['settings']['looping']
 
     def to_ffmpeg(self, scene):
-        return [], [FFmpegChain(
-            FFmpegFilter('movie',  filename=self.infile, loop=0 if self.loop else 1),
-            FFmpegFilter('realtime')
+        return [FFmpegChain(
+            FFmpegFilter('realtime'),
+            inputs=[FFmpegInput(self.infile, re=None)]
         )]

src/overlay/twitch_chat.py

@@ -9,7 +9,7 @@ def make_twitch_chat(name, nickname, token, channel, x=200, y=25, addr='tcp://lo
     nick_id = 'drawtext@twitch-{}-nicks'.format(name)
     chat_id = 'drawtext@twitch-{}-messages'.format(name)
     runner = TwitchChatUpdater(nickname=nickname, token=token, channel=channel, nick_target=nick_id, chat_target=chat_id)
-    return [runner.run], [FFmpegChain(
+    return [FFmpegChain(
         FFmpegFilter(nick_id,
             text='Loading',
             expansion='none',
@@ -24,7 +24,8 @@ def make_twitch_chat(name, nickname, token, channel, x=200, y=25, addr='tcp://lo
             y=y,
             **chat_args
         ),
-        FFmpegFilter('zmq')
+        FFmpegFilter('zmq'),
+        runners=[runner.run]
     )]
 
 def zmq_escape(v):