advancedav: Work towards 3.0: Actually use ffprobe properly

lib/python/advancedav.py

@@ -1,5 +1,5 @@
 """
-AdvancedAV FFmpeg commandline generator v2.0 [Library Edition]
+AdvancedAV FFmpeg commandline generator v3.0 [Library Edition]
 -----------------------------------------------------------
     AdvancedAV helps with constructing FFmpeg commandline arguments.
 
@@ -23,23 +23,21 @@ AdvancedAV FFmpeg commandline generator v2.0 [Library Edition]
 """
 
 import os
-import re
+import sys
+import json
+import logging
 import subprocess
 import collections
 import itertools
 
 from abc import ABCMeta, abstractmethod
-from collections.abc import Iterable, Mapping, Sequence, Iterator, MutableMapping
+from typing import Iterable, Mapping, Sequence, Iterator, MutableMapping
-
+from pathlib import Path, PurePath
-try:
-    from pathlib import Path, PurePath
-except ImportError:
-    pass
 
 
 __all__ = "AdvancedAVError", "AdvancedAV", "SimpleAV"
 
-version_info = 2, 1, 1
+version_info = 2, 99, 0
 
 # Constants
 DEFAULT_CONTAINER = "matroska"
@@ -57,8 +55,40 @@ class AdvancedAVError(Exception):
     pass
 
 
+# == Helpers ==
+def ffmpeg_int(no: str) -> int:
+    if isinstance(no, str):
+        factor = 1
+        base = 1000
+        if no[-1].lower() == "b":
+            factor *= 8
+            no = no[:-1]
+        if no[-1].lower() == "i":
+            base = 1024
+            no = no[:-1]
+        if not no[-1].isdigit():
+            factor *= base ** (["k", "m", "g"].index(no[-1].lower()) + 1)
+            no = no[:-1]
+        return int(no) * factor
+    return int(no)
+
+
 # == Base Classes ==
 class ObjectWithOptions:
+    """
+    Options refer to ffmpeg commandline arguments, referring to a specific Task, File or Stream.
+
+    Option values can be:
+        - str: pass value
+        - int: convert to string, pass value
+        - list, tuple: pass option multiple times, with different values
+        - True: pass option without value
+        - None: pass option without value (deprecated)
+
+    For option names, refer to the FFmpeg documentation.
+
+    Subclasses must provide an 'options' slot.
+    """
     __slots__ = ()
 
     def __init__(self, *, options=None, **more):
@@ -66,6 +96,14 @@ class ObjectWithOptions:
         self.options = options or {}
 
     def apply(self, source, *names, **omap):
+        """
+        Selectively apply options from a dictionary.
+
+        Option names passed as strings will be applied as-is,
+        option names passed as keyword arguments will be applied as though they were named the argument's value
+
+        :return: self, for method chaining
+        """
         for name in names:
             if name in source:
                 self.options[name] = source[name]
@@ -76,6 +114,13 @@ class ObjectWithOptions:
         return self
 
     def set(self, **options):
+        """
+        Set options on this object
+
+        Applies all keyword arguments as options
+
+        :return: self, for method chaining
+        """
         self.options.update(options)
         return self
 
@@ -102,6 +147,89 @@ class ObjectWithMetadata:
         return self
 
 
+# == Descriptors ==
+class DescriptorBase:
+    __slots__ = "owner", "name"
+
+    def __init__(self, default_name="(Name Unknown)"):
+        self.owner = None
+        self.name = default_name
+
+    def __set_name__(self, owner, name):
+        self.owner = owner
+        self.name = name
+
+    repr_info = ""
+
+    def __repr__(self):
+        return "<%s %s of %s%s>" % (type(self).__name__, self.name, self.owner, self.repr_info)
+
+
+class InformationProperty(DescriptorBase):
+    """
+    A read-only property referring ffprobe information
+    """
+    __slots__ = "path", "type"
+
+    def __init__(self, *path, type=lambda x: x):
+        super().__init__()
+        self.path = path
+        self.type = type
+
+    @property
+    def repr_info(self):
+        return " referring to %s" % self.path
+
+    def __get__(self, object, obj_type=None):
+        info = object.information
+        try:
+            for seg in self.path:
+                info = info[seg]
+        except (KeyError, IndexError):
+            return None
+        else:
+            return self.type(info)
+
+
+class OptionProperty(DescriptorBase):
+    """
+    A read-write descriptor referring to ffmpeg options
+
+    Unset options will return None,
+    setting an option to None will unset it.
+
+    Note: This differs from deprecated behaviour when setting options directly,
+          which will cause the option to be passed without arguments.
+    """
+    __slots__ = "candidates", "type"
+
+    def __init__(self, *candidates, type=lambda x: x):
+        super().__init__()
+        self.candidates = candidates
+        self.type = type
+
+    @property
+    def repr_info(self):
+        return " referencing option %s" % self.candidates[0]
+
+    def __get__(self, object, obj_type=None):
+        for candidate in self.candidates:
+            if candidate in object.options:
+                return self.type(object.options[candidate])
+        else:
+            return None
+
+    def __set__(self, object, value):
+        for candidate in self.candidates:
+            if candidate in object.options:
+                del object.options[candidate]
+        if value is not None:
+            object.options[self.candidates[0]] = value
+
+    def __delete__(self, object):
+        self.__set__(object, None)
+
+
 # === Stream Classes ===
 class Stream:
     """
@@ -109,23 +237,23 @@ class Stream:
 
     One continuous stream of data muxed into a container format
     """
-    __slots__ = "file", "type", "index", "pertype_index", "codec", "profile"
+    __slots__ = "file",
 
-    def __init__(self, file: "File", type: str, index: int=None, pertype_index: int=None,
+    def __init__(self, file: "File", **more):
-                 codec: str=None, profile: str=None, **more):
         super().__init__(**more)
         self.file = file
-        self.type = type
-        self.index = index
-        self.pertype_index = pertype_index
-        self.codec = codec
-        self.profile = profile
 
-    def _update_indices(self, index: int, pertype_index: int=None):
+    @property
-        """ Update the Stream indices """
+    def index(self):
-        self.index = index
+        return 0
-        if pertype_index is not None:
+
-            self.pertype_index = pertype_index
+    @property
+    def pertype_index(self):
+        return None
+
+    @property
+    def type(self):
+        return S_UNKNOWN
 
     @property
     def stream_spec(self):
@@ -135,47 +263,108 @@ class Stream:
         else:
             return str(self.index)
 
-    def __str__(self):
+    def __repr__(self):
-        return "<%s %s#%i: %s %s (%s)>" % (type(self).__name__, self.file.name, self.index,
+        return "<%s \"%s\"#%i (%s#%i)>" % (type(self).__name__, self.file.name, self.index, self.type, self.pertype_index)
-                                           self.type, self.codec, self.profile)
 
 
+# Input Streams
 class InputStream(Stream):
     """
     Holds information about an input stream
     """
-    __slots__ = "language"
+    __slots__ = "information", "pertype_index"
 
-    def __init__(self, file: "InputFile", type_: str, index: int, language: str, codec: str, profile: str):
+    def __init__(self, file: "InputFile", info: dict, pertype_index: int=None):
-        super().__init__(file, type_, index, codec=codec, profile=profile)
+        super().__init__(file)
-        self.file = file
-        self.language = language
 
-    def _update_indices(self, index: int, pertype_index: int=None):
+        self.information = info
-        """ InputStreams should not have their indices changed. """
+        self.pertype_index = pertype_index
-        if index != self.index:
+
-            raise ValueError("Cannot update indices on InputStreams! (This might mean there are bogus ids in the input")
+    @property
-        # pertype_index gets updated by File._add_stream() so we don't throw up if it gets updated
+    def type(self):
+        return self.information["codec_type"][0]
+
+    index       = InformationProperty("index", type=int)
+
+    codec       = InformationProperty("codec_name")
+    codec_name  = InformationProperty("codec_long_name")
+    profile     = InformationProperty("profile")
 
+    duration    = InformationProperty("duration", type=float)
+    duration_ts = InformationProperty("duration_ts", type=int)
+
+    start_time  = InformationProperty("start_time")
+
+    bitrate     = InformationProperty("bit_rate", type=int)
+    max_bitrate = InformationProperty("max_bit_rate", type=int)
+    nb_frames   = InformationProperty("nb_frames", type=int)
+
+    @property
+    def disposition(self):
+        try:
+            return tuple(k for k, v in self.information["disposition"].items() if v)
+        except KeyError:
+            return ()
 
+    language    = InformationProperty("tags", "language")
+
+
+class InputAudioStream(InputStream):
+    __slots__ = ()
+
+    def  __init__(self, file: "InputFile", info: dict, pertype_index: int=None):
+        if info["codec_type"][0] != S_AUDIO:
+            raise ValueError("Cannot create %s from stream info of type %s" % (type(self).__name__, info["codec_type"]))
+
+        super().__init__(file, info)
+
+    @property
+    def type(self):
+        return S_AUDIO
+
+    sample_format   = InformationProperty("sample_format")
+    sample_rate     = InformationProperty("sample_rate", type=int)
+
+    channels        = InformationProperty("channels", type=int)
+    channel_layout  = InformationProperty("channel_layout")
+
+
+def input_stream_factory(file, info, pertype_index=None):
+    return {
+        "audio": InputAudioStream,
+    }.get(info["codec_type"], InputStream)(file, info, pertype_index)
+
+
+# Output Streams
 class OutputStream(Stream, ObjectWithOptions, ObjectWithMetadata):
     """
     Holds information about a mapped output stream
     """
-    __slots__ = "source", "options", "metadata"
+    __slots__ = "index", "pertype_index", "source", "options", "metadata"
 
     # TODO: support other parameters like frame resolution
 
-    # Override polymorphic types
-    #file = None
-    """ :type: OutputFile """
-
     def __init__(self, file: "OutputFile", source: InputStream, stream_id: int, stream_pertype_id: int=None,
-                 codec: str=None, options: Mapping=None, metadata: MutableMapping=None):
+                 options: Mapping=None, metadata: MutableMapping=None):
-        super().__init__(file=file, type=source.type, index=stream_id, pertype_index=stream_pertype_id,
+        super().__init__(file=file, options=options, metadata=metadata)
-            codec=codec, options=options, metadata=metadata)
+        self.index = stream_id
+        self.pertype_index = stream_pertype_id
         self.source = source
 
+    @property
+    def type(self):
+        return self.source.type
+
+    def _update_indices(self, index: int, pertype_index: int=None):
+        """ Update the Stream indices """
+        self.index = index
+        if pertype_index is not None:
+            self.pertype_index = pertype_index
+
+    codec = OptionProperty("codec", "c")
+
+    bitrate = OptionProperty("b", type=ffmpeg_int)
+
 
 class OutputVideoStream(OutputStream):
     def downscale(self, width, height):
@@ -185,7 +374,9 @@ class OutputVideoStream(OutputStream):
 
 
 def output_stream_factory(file, source, *args, **more):
-    return (OutputVideoStream if source.type == S_VIDEO else OutputStream)(file, source, *args, **more)
+    return {
+        S_VIDEO: OutputVideoStream,
+    }.get(source.type, OutputStream)(file, source, *args, **more)
 
 
 # === File Classes ===
@@ -193,20 +384,12 @@ class File(ObjectWithOptions):
     """
     ABC for Input- and Output-Files
     """
-    __slots__ = "name", "_streams", "_streams_by_type", "options", "path"
+    __slots__ = "_streams", "_streams_by_type", "options", "path"
 
-    def __init__(self, name: str, options: dict=None, **more):
+    def __init__(self, path: Path, options: dict=None, **more):
         super().__init__(options=options, **more)
 
-        if Path: # Need to 
+        self.path = Path(path)
-            self.path = Path(name)
-            self.name = str(name)
-        else:
-            self.name = name
-
-
-        self.options = options if options is not None else {}
-        """ :type: dict[str, str] """
 
         self._streams = []
         """ :type: list[Stream] """
@@ -214,6 +397,31 @@ class File(ObjectWithOptions):
         self._streams_by_type = collections.defaultdict(list)
         """ :type: dict[str, list[Stream]] """
 
+    # Filename
+    @property
+    def name(self):
+        """
+        The file's name
+        Changed in 3.0: previously, full path
+        """
+        return self.path.name
+
+    @name.setter
+    def name(self, value):
+        self.path = self.path.with_name(value)
+
+    @property
+    def filename(self):
+        """
+        The file's full path as string
+        """
+        return str(self.path)
+
+    @filename.setter
+    def filename(self, value):
+        self.path = Path(value)
+
+    # Streams
     def _add_stream(self, stream: Stream):
         """ Add a stream """
         stream._update_indices(len(self._streams), len(self._streams_by_type[stream.type]))
@@ -268,13 +476,26 @@ class File(ObjectWithOptions):
         """
         return self._streams_by_type[S_DATA]
 
-    @property
+    def __repr__(self):
-    def filename(self) -> str:
+        return "<%s \"%s\">" % (type(self).__name__, self.name)
-        """ Alias for .name """
+
-        return self.name
+
+class InputFileChapter:
+    __slots__ = "file", "information"
+
+    def __init__(self, file, info):
+        self.file = file
+        self.information = info
+
+    def __repr__(self):
+        return "<InputFileChapter #%i of %s from %.0fs to %.0fs (%s)>" \
+                % (self.index, self.file, self.start_time, self.end_time, self.title)
 
-    def __str__(self):
+    start_time  = InformationProperty("start_time", type=float)
-        return "<%s %s>" % (type(self).__name__, self.name)
+    end_time    = InformationProperty("end_time", type=float)
+
+    index       = InformationProperty("id", type=int)
+    title       = InformationProperty("tags", "title")
 
 
 class InputFile(File):
@@ -284,65 +505,50 @@ class InputFile(File):
     :note: Modifying the options after accessing the streams results in undefined
             behaviour! (Currently: Changes will only apply to conv call)
     """
-    __slots__ = "pp", "_streams_initialized"
+    __slots__ = "pp", "_information"
 
-    stream_factory = InputStream
+    stream_factory = staticmethod(input_stream_factory)
 
-    def __init__(self, pp: "AdvancedAV", filename: str, options: Mapping=None):
+    def __init__(self, pp: "AdvancedAV", path: str, options: Mapping=None, info=None):
-        super().__init__(name=filename, options=dict(options.items()) if options else None)
+        super().__init__(path, options=dict(options.items()) if options else None)
 
         self.pp = pp
+        self._information = info
 
-        self._streams_initialized = False
+    @property
+    def information(self):
+        if self._information is None:
+            self._initialize_info()
+        return self._information
 
-    # -- Probe streams
+    # -- Initialize
-    _reg_probe_streams = re.compile(
+    ffprobe_args = "-show_format", "-show_streams", "-show_chapters", "-print_format", "json"
-        r"Stream #0:(?P<id>\d+)(?:\((?P<lang>[^\)]+)\))?:\s+(?P<type>\w+):\s+(?P<codec>[\w_\d]+)"
-        r"(?:\s+\((?P<profile>[^\)]+)\))?(?:\s+(?P<extra>.+))?"
-    )
 
-    @staticmethod
+    def _initialize_info(self):
-    def _stream_type(type_: str) -> str:
+        probe = self.pp.call_probe(tuple(Task.argv_options(self.options))
-        """ Convert the ff-/avprobe type output to the notation used on the ffmpeg/avconv commandline """
+                                    + self.ffprobe_args
-        lookup = {
+                                    + ("-i", self.filename))
-            "Audio": S_AUDIO,
+        self._information = json.loads(probe)
-            "Video": S_VIDEO,
+
-            "Subtitle": S_SUBTITLE,
+    def _initialize_streams(self):
-            "Attachment": S_ATTACHMENT,
-            "Data": S_DATA
-        }
-
-        return lookup.get(type_, S_UNKNOWN)
-
-    def _initialize_streams(self, probe: str=None) -> Iterator:
         """ Parse the ffprobe output
 
         The locale of the probe output in \param probe should be C!
-
-        :rtype: Iterator[InputStream]
         """
-        if probe is None:
+        for sinfo in self.information["streams"]:
-            if self.options:
+            stype = sinfo["codec_type"][0]
-                probe = self.pp.call_probe(itertools.chain(Task.argv_options(self.options), ("-i", self.name)))
+            stream = self.stream_factory(self, sinfo, len(self._streams_by_type[stype]))
-            else:
+            self._streams.append(stream)
-                probe = self.pp.call_probe(("-i", self.name))
+            self._streams_by_type[stype].append(stream)
-
-        for match in self._reg_probe_streams.finditer(probe):
-            self._add_stream(self.stream_factory(self,
-                                                 self._stream_type(match.group("type")),
-                                                 int(match.group("id")),
-                                                 match.group("lang"),
-                                                 match.group("codec"),
-                                                 match.group("profile")))
-        self._streams_initialized = True
 
+    # -- Streams
     @property
     def streams(self) -> Sequence:
         """ Collect the available streams
 
         :rtype: Sequence[InputStream]
         """
-        if not self._streams_initialized:
+        if not self._streams:
             self._initialize_streams()
         return self._streams
 
@@ -352,7 +558,7 @@ class InputFile(File):
 
         :rtype: Sequence[InputStream]
         """
-        if not self._streams_initialized:
+        if not self._streams:
             self._initialize_streams()
         return self._streams_by_type[S_VIDEO]
 
@@ -362,7 +568,7 @@ class InputFile(File):
 
         :rtype: Sequence[InputStream]
         """
-        if not self._streams_initialized:
+        if not self._streams:
             self._initialize_streams()
         return self._streams_by_type[S_AUDIO]
 
@@ -372,7 +578,7 @@ class InputFile(File):
 
         :rtype: Sequence[InputStream]
         """
-        if not self._streams_initialized:
+        if not self._streams:
             self._initialize_streams()
         return self._streams_by_type[S_SUBTITLE]
 
@@ -382,7 +588,7 @@ class InputFile(File):
 
         :rtype: Sequence[InputStream]
         """
-        if not self._streams_initialized:
+        if not self._streams:
             self._initialize_streams()
         return self._streams_by_type[S_ATTACHMENT]
 
@@ -392,10 +598,30 @@ class InputFile(File):
 
         :rtype: Sequence[InputStream]
         """
-        if not self._streams_initialized:
+        if not self._streams:
             self._initialize_streams()
         return self._streams_by_type[S_DATA]
 
+    # Information
+    nb_streams  = InformationProperty("format", "nb_streams", type=int)
+
+    duration    = InformationProperty("format", "duration", type=float)
+
+    size        = InformationProperty("format", "size", type=int)
+    bitrate     = InformationProperty("format", "bit_rate", type=int)
+
+    # Metadata
+    metadata    = InformationProperty("format", "tags")
+
+    title       = InformationProperty("format", "tags", "title")
+    artist      = InformationProperty("format", "tags", "artist")
+    album       = InformationProperty("format", "tags", "album")
+
+    # Chapters
+    @property
+    def chapters(self) -> Sequence[InputFileChapter]:
+        return list(InputFileChapter(self, i) for i in self.information["chapters"])
+
 
 class OutputFile(File, ObjectWithMetadata):
     """
@@ -539,7 +765,7 @@ class Task:
         :param file: Can be either the filename of an input file or an InputFile object.
                         The latter will be created if the former is passed.
         """
-        if  PurePath and isinstance(file, PurePath): # Pathlib support
+        if  isinstance(file, PurePath): # Pathlib support
             file = str(file)
         if  isinstance(file, str):
             if file in self.inputs_by_name:
@@ -550,7 +776,7 @@ class Task:
         if file not in self.inputs:
             self.pp.to_debug("Adding input file #%i: %s", len(self.inputs), file.name)
             self.inputs.append(file)
-            self.inputs_by_name[file.name] = file
+            self.inputs_by_name[file.filename] = file
 
         return file
 
@@ -570,7 +796,7 @@ class Task:
         NOTE: Contrary to add_input this will NOT take an OutputFile instance and return it.
         """
         for outfile in self.outputs:
-            if outfile.name == filename:
+            if outfile.filename == filename:
                 raise AdvancedAVError("Output File '%s' already added." % filename)
         else:
             outfile = self.output_factory(self, filename, container, options)
@@ -603,6 +829,10 @@ class Task:
         for input_ in self.inputs:
             yield from input_.streams
 
+    def iter_chapters(self) -> Iterator[InputFileChapter]:
+        for input_ in self.inputs:
+            yield from input_.chapters
+
     # -- FFmpeg
     @staticmethod
     def argv_options(options: Mapping, qualifier: str=None) -> Iterator:
@@ -618,12 +848,12 @@ class Task:
         for option, value in options.items():
             yield opt_fmt % option
             if isinstance(value, (tuple, list)):
-                yield value[0]
+                yield str(value[0])
                 for x in value[1:]:
                     yield opt_fmt % option
-                    yield x
+                    yield str(x)
-            elif value is not None:
+            elif value is not True and value is not None:
-                yield value
+                yield str(value)
 
     @staticmethod
     def argv_metadata(metadata: Mapping, qualifier: str=None) -> Iterator:
@@ -652,7 +882,7 @@ class Task:
 
             # Add Input
             yield "-i"
-            filename = input_.name
+            filename = input_.filename
             if filename[0] == '-':
                 yield "./" + filename
             else:
@@ -684,7 +914,7 @@ class Task:
                 yield output.container
 
             # Output Filename, prevent it from being interpreted as option
-            out_fn = output.name
+            out_fn = output.filename
             yield out_fn if out_fn[0] != "-" else "./" + out_fn
 
     def commit(self, additional_args: Iterable=()):
@@ -726,7 +956,8 @@ class SimpleTask(Task):
     container = _redir("output", "container")
     metadata = _redir("output", "metadata")
     options = _redir("output", "options")
-    name = _redir("output", "name")
+    name = _redir("output", "name") # Deprecated! use filename instead. 'name' will be reused in the future
+    filename = _redir("output", "name")
 
     del _redir
 
@@ -737,14 +968,17 @@ class AdvancedAV(metaclass=ABCMeta):
 
     # ---- Output ----
     @abstractmethod
-    def to_screen(self, text: str, *fmt):
+    def get_logger(self):
-        """ Log messages to the user """
+        """
+        Get a stdlib logger to output to
+        """
         pass
 
-    @abstractmethod
+    def to_screen(self, text, *fmt):
-    def to_debug(self, text: str, *fmt):
+        self.get_logger().log(text % fmt)
-        """ Process verbose messages """
+
-        pass
+    def to_debug(self, text, *fmt):
+        self.get_logger().debug(text % fmt)
 
     # ---- FFmpeg ----
     @abstractmethod
@@ -793,7 +1027,7 @@ class AdvancedAV(metaclass=ABCMeta):
         :return: A InputFile instance
         NOTE that Task.add_input is usually the preferred way to create inputs
         """
-        return self.input_factory(pp=self, filename=filename, options=options)
+        return self.input_factory(self, filename, options=options)
 
 
 class SimpleAV(AdvancedAV):
@@ -808,7 +1042,6 @@ class SimpleAV(AdvancedAV):
 
     def __init__(self, *, ffmpeg="ffmpeg", ffprobe="ffprobe", logger=None, ffmpeg_output=True):
         if logger is None:
-            import logging
             self.logger = logging.getLogger("advancedav.SimpleAV")
         else:
             self.logger = logger
@@ -817,11 +1050,8 @@ class SimpleAV(AdvancedAV):
         self.ffmpeg_output = ffmpeg_output
         self.logger.debug("SimpleAV initialized.")
 
-    def to_screen(self, text, *fmt):
+    def get_logger(self):
-        self.logger.log(text % fmt)
+        return self.logger
-
-    def to_debug(self, text, *fmt):
-        self.logger.debug(text % fmt)
 
     _posix_env = dict(os.environ)
     _posix_env["LANG"] = _posix_env["LC_ALL"] = "C"
@@ -857,4 +1087,4 @@ class SimpleAV(AdvancedAV):
             msg = err.strip().split('\n')[-1]
             raise AdvancedAVError(msg)
 
-        return err.decode("utf-8", "replace")
+        return out.decode("utf-8", "replace")