dom/media/flac/FlacFrameParser.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   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 FLAC_FRAME_PARSER_H_
   8 #define FLAC_FRAME_PARSER_H_
   9
  10 #include "mozilla/Maybe.h"
  11 #include "mozilla/Result.h"
  12 #include "MediaDecoder.h"  // For MetadataTags
  13 #include "MediaInfo.h"
  14 #include "MediaResource.h"
  15
  16 namespace mozilla {
  17
  18 #define FLAC_MAX_CHANNELS 8
  19 #define FLAC_MIN_BLOCKSIZE 16
  20 #define FLAC_MAX_BLOCKSIZE 65535
  21 #define FLAC_MIN_FRAME_SIZE 11
  22 #define FLAC_MAX_FRAME_HEADER_SIZE 16
  23 #define FLAC_MAX_FRAME_SIZE \
  24   (FLAC_MAX_FRAME_HEADER_SIZE + FLAC_MAX_BLOCKSIZE * FLAC_MAX_CHANNELS * 3)
  25
  26 class OpusParser;
  27
  28 // Decode a Flac Metadata block contained in either a ogg packet
  29 // (https://xiph.org/flac/ogg_mapping.html) or in flac container
  30 // (https://xiph.org/flac/format.html#frame_header)
  31
  32 class FlacFrameParser {
  33  public:
  34   FlacFrameParser();
  35   ~FlacFrameParser();
  36
  37   Result<bool, nsresult> IsHeaderBlock(const uint8_t* aPacket,
  38                                        size_t aLength) const;
  39   // Return the length of the block header (METADATA_BLOCK_HEADER+
  40   // METADATA_BLOCK_DATA), aPacket must point to at least 4
  41   // bytes and to a valid block header start (as determined by IsHeaderBlock).
  42   uint32_t HeaderBlockLength(const uint8_t* aPacket) const;
  43   Result<Ok, nsresult> DecodeHeaderBlock(const uint8_t* aPacket,
  44                                          size_t aLength);
  45   bool HasFullMetadata() const { return mFullMetadata; }
  46   // Return the duration in frames found in the block. -1 if error
  47   // such as invalid packet.
  48   int64_t BlockDuration(const uint8_t* aPacket, size_t aLength) const;
  49
  50   // Return a hash table with tag metadata.
  51   UniquePtr<MetadataTags> GetTags() const;
  52
  53   AudioInfo mInfo;
  54
  55  private:
  56   bool ReconstructFlacGranulepos(void);
  57   Maybe<uint32_t> mNumHeaders;
  58   uint32_t mMinBlockSize;
  59   uint32_t mMaxBlockSize;
  60   uint32_t mMinFrameSize;
  61   uint32_t mMaxFrameSize;
  62   uint64_t mNumFrames;
  63   bool mFullMetadata;
  64   uint32_t mPacketCount;
  65
  66   // Used to decode the vorbis comment metadata.
  67   UniquePtr<OpusParser> mParser;
  68 };
  69
  70 }  // namespace mozilla
  71
  72 #endif  // FLAC_FRAME_PARSER_H_