Add VideoFrame.save(path, ...) method.

av/codec/codec.pyx

@@ -86,6 +86,9 @@ cdef class Codec(object):
         if self.is_encoder and lib.av_codec_is_decoder(self.ptr):
             raise RuntimeError('%s is both encoder and decoder.')
 
+    def __repr__(self):
+        return '<av.Codec {!r} mode={!r} at 0x{:x}>'.format(self.name, 'w' if self.is_encoder else 'r', id(self))
+
     def create(self):
         from .context import CodecContext
         return CodecContext.create(self)

av/video/format.pyx

@@ -53,6 +53,16 @@ cdef class VideoFormat(object):
     def __int__(self):
         return int(self.pix_fmt)
 
+    def __eq__(self, other):
+        if isinstance(other, VideoFormat):
+            return (
+                self.pix_fmt == int(other) and
+                self.width == other.width and
+                self.height == other.height
+            )
+        else:
+            raise TypeError("Cannot compare VideoFormat to {}.".format(type(other)))
+
     property name:
         """Canonical name of the pixel format."""
         def __get__(self):

av/video/frame.pyx

 from libc.stdint cimport uint8_t
 
+from av.codec.codec cimport Codec
+from av.codec.context cimport CodecContext
 from av.deprecation import renamed_attr
 from av.enums cimport define_enum
 from av.error cimport err_check
 from av.video.format cimport get_video_format, VideoFormat
 from av.video.plane cimport VideoPlane
 
+import os
+
 
 cdef object _cinit_bypass_sentinel
 
@@ -330,6 +334,47 @@ cdef class VideoFrame(Frame):
         """
         return self.reformat(format="rgb24", **kwargs)
 
+    def save(self, path, codec=None, format=None, options=None):
+
+        if not codec:
+            ext = os.path.splitext(path)[1].lower()
+            if not ext:
+                raise ValueError("Please provide a codec or a path with an extension.")
+            codec_name = {
+                '.jpg': 'mjpeg',
+                '.jpeg': 'mjpeg',
+                '.tif': 'tiff',
+            }.get(ext, ext[1:])
+            codec = Codec(codec_name, 'w')
+
+        elif not isinstance(codec, Codec):
+            codec = Codec(codec, 'w')
+
+        given_format = format is not None
+        format = VideoFormat(format or self.format)
+        if not any(format.name == f.name for f in codec.video_formats):
+            if given_format:
+                raise ValueError("Format {!r} is not in codec.video_formats.".format(format))
+            format = codec.video_formats[0]
+
+        to_encode = self.reformat(format=format)
+
+        ctx = codec.create()
+        ctx.width = self.width
+        ctx.height = self.height
+        ctx.pix_fmt = format.name
+        if options:
+            ctx.options.update(options)
+        ctx.open()
+
+        packets = ctx.encode(to_encode)
+
+        if len(packets) != 1:
+            raise ValueError("Frame encoded to {} packets; expected 1.".format(len(packets)))
+
+        with open(path, 'wb') as fh:
+            fh.write(packets[0])
+
     def to_image(self, **kwargs):
         """Get an RGB ``PIL.Image`` of this frame.
 

examples/basics/save_keyframes.py

@@ -14,7 +14,8 @@ for frame in container.decode(stream):
     print(frame)
 
     # We use `frame.pts` as `frame.index` won't make must sense with the `skip_frame`.
-    frame.to_image().save(
+    frame.save(
         'night-sky.{:04d}.jpg'.format(frame.pts),
-        quality=80,
+        # format='yuv420p'
+        # quality=80,
     )

tests/test_videoformat.py

@@ -88,3 +88,16 @@ class TestVideoFormats(TestCase):
         fmt = VideoFormat('pal8', 640, 480)
         self.assertEqual(len(fmt.components), 1)
         self.assertTrue(fmt.has_palette)
+
+    def test_equality(self):
+
+        a = VideoFormat('yuv420p')
+        b = VideoFormat('yuv420p')
+        c = VideoFormat('rgb24')
+
+        self.assertIsNot(a, b)
+        self.assertEqual(a, b)
+        self.assertNotEqual(a, c)
+
+        self.assertIn(a, [b, c])
+        self.assertNotIn(a, [c])