Support input/output parameters

ffmpeg/_ffmpeg.py

@@ -8,12 +8,17 @@ from .nodes import (
 )
 
 
-def input(filename):
+def input(filename, **kwargs):
     """Input file URL (ffmpeg ``-i`` option)
 
     Official documentation: `Main options <https://ffmpeg.org/ffmpeg.html#Main-options>`__
     """
-    return InputNode(input.__name__, filename=filename)
+    kwargs['filename'] = filename
+    fmt = kwargs.pop('f', None)
+    if fmt:
+        assert 'format' not in kwargs, "Can't specify both `format` and `f` kwargs"
+        kwargs['format'] = fmt
+    return InputNode(input.__name__, **kwargs)
 
 
 @operator(node_classes={OutputNode, GlobalNode})
@@ -31,12 +36,17 @@ def merge_outputs(*parent_nodes):
 
 
 @operator(node_classes={InputNode, FilterNode})
-def output(parent_node, filename):
+def output(parent_node, filename, **kwargs):
     """Output file URL
 
     Official documentation: `Synopsis <https://ffmpeg.org/ffmpeg.html#Synopsis>`__
     """
-    return OutputNode([parent_node], output.__name__, filename=filename)
+    kwargs['filename'] = filename
+    fmt = kwargs.pop('f', None)
+    if fmt:
+        assert 'format' not in kwargs, "Can't specify both `format` and `f` kwargs"
+        kwargs['format'] = fmt
+    return OutputNode([parent_node], output.__name__, **kwargs)
 
 
 

ffmpeg/_run.py

@@ -1,6 +1,8 @@
 from __future__ import unicode_literals
 
+from functools import reduce
 from past.builtins import basestring
+import copy
 import operator as _operator
 import subprocess as _subprocess
 
@@ -16,7 +18,6 @@ from .nodes import (
     operator,
     OutputNode,
 )
-from functools import reduce
 
 def _get_stream_name(name):
     return '[{}]'.format(name)
@@ -24,7 +25,20 @@ def _get_stream_name(name):
 
 def _get_input_args(input_node):
     if input_node._name == input.__name__:
-        args = ['-i', input_node._kwargs['filename']]
+        kwargs = copy.copy(input_node._kwargs)
+        filename = kwargs.pop('filename')
+        fmt = kwargs.pop('format', None)
+        video_size = kwargs.pop('video_size', None)
+        args = []
+        if fmt:
+            args += ['-f', fmt]
+        if video_size:
+            args += ['-video_size', '{}x{}'.format(video_size[0], video_size[1])]
+        for k, v in kwargs.items():
+            args.append('-{}'.format(k))
+            if v:
+                args.append('{}'.format(v))
+        args += ['-i', filename]
     else:
         assert False, 'Unsupported input node: {}'.format(input_node)
     return args
@@ -78,7 +92,17 @@ def _get_output_args(node, stream_name_map):
         if stream_name != '[0]':
             args += ['-map', stream_name]
         if node._name == output.__name__:
-            args += [node._kwargs['filename']]
+            kwargs = copy.copy(node._kwargs)
+            filename = kwargs.pop('filename')
+            fmt = kwargs.pop('format', None)
+
+            if fmt:
+                args += ['-f', fmt]
+            for k, v in kwargs.items():
+                args.append('-{}'.format(k))
+                if v:
+                    args.append('{}'.format(v))
+            args += [filename]
         else:
             assert False, 'Unsupported output node: {}'.format(node)
     return args

ffmpeg/tests/test_ffmpeg.py

@@ -3,6 +3,7 @@ import ffmpeg
 import os
 import pytest
 import subprocess
+import random
 
 
 TEST_DIR = os.path.dirname(__file__)
@@ -167,3 +168,41 @@ def test_custom_filter_fluent():
         '-map', '[v0]',
         'dummy2.mp4'
     ]
+
+
+def test_pipe():
+    width = 32
+    height = 32
+    frame_size = width * height * 3  # 3 bytes for rgb24
+    frame_count = 10
+    start_frame = 2
+
+    out = (ffmpeg
+        .input('pipe:0', format='rawvideo', pixel_format='rgb24', video_size=(width, height), framerate=10)
+        .trim(start_frame=start_frame)
+        .output('pipe:1', format='rawvideo')
+    )
+    args = out.get_args()
+    assert args == [
+        '-f', 'rawvideo',
+        '-video_size', '{}x{}'.format(width, height),
+        '-pixel_format', 'rgb24',
+        '-framerate', '10',
+        '-i', 'pipe:0',
+        '-filter_complex',
+            '[0]trim=start_frame=2[v0]',
+        '-map', '[v0]',
+        '-f', 'rawvideo',
+        'pipe:1'
+    ]
+
+    cmd = ['ffmpeg'] + args
+    p = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+
+    in_data = bytes(bytearray([random.randint(0,255) for _ in range(frame_size * frame_count)]))
+    p.stdin.write(in_data)
+    p.stdin.close()
+
+    out_data = p.stdout.read()
+    assert len(out_data) == frame_size * (frame_count - start_frame)
+    assert out_data == in_data[start_frame*frame_size:]