content/media/DecoderTraits.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim:set ts=2 sw=2 sts=2 et cindent: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef DecoderTraits_h_
   8 #define DecoderTraits_h_
   9
  10 #include "nsCOMPtr.h"
  11
  12 class nsAString;
  13 class nsACString;
  14
  15 namespace mozilla {
  16
  17 class AbstractMediaDecoder;
  18 class MediaDecoder;
  19 class MediaDecoderOwner;
  20 class MediaDecoderReader;
  21
  22 enum CanPlayStatus {
  23   CANPLAY_NO,
  24   CANPLAY_MAYBE,
  25   CANPLAY_YES
  26 };
  27
  28 class DecoderTraits {
  29 public:
  30   // Returns the CanPlayStatus indicating if we can handle this
  31   // MIME type. The MIME type should not include the codecs parameter.
  32   // That parameter should be passed in aCodecs, and will only be
  33   // used if whether a given MIME type being handled depends on the
  34   // codec that will be used.  If the codecs parameter has not been
  35   // specified, pass false in aHaveRequestedCodecs.
  36   static CanPlayStatus CanHandleMediaType(const char* aMIMEType,
  37                                           bool aHaveRequestedCodecs,
  38                                           const nsAString& aRequestedCodecs);
  39
  40   // Returns true if we should handle this MIME type when it appears
  41   // as an <object> or as a toplevel page. If, in practice, our support
  42   // for the type is more limited than appears in the wild, we should return
  43   // false here even if CanHandleMediaType would return true.
  44   static bool ShouldHandleMediaType(const char* aMIMEType);
  45
  46   // Create a decoder for the given aType. Returns null if we
  47   // were unable to create the decoder.
  48   static already_AddRefed<MediaDecoder> CreateDecoder(const nsACString& aType,
  49                                                       MediaDecoderOwner* aOwner);
  50
  51   // Create a reader for thew given MIME type aType. Returns null
  52   // if we were unable to create the reader.
  53   static MediaDecoderReader* CreateReader(const nsACString& aType,
  54                                           AbstractMediaDecoder* aDecoder);
  55
  56   // Returns true if MIME type aType is supported in video documents,
  57   // or false otherwise. Not all platforms support all MIME types, and
  58   // vice versa.
  59   static bool IsSupportedInVideoDocument(const nsACString& aType);
  60
  61   // Returns true if we should not start decoder until we receive
  62   // OnConnected signal. (currently RTSP only)
  63   static bool DecoderWaitsForOnConnected(const nsACString& aType);
  64 };
  65
  66 }
  67
  68 #endif
  69