gecko-dev/dom/media/flac/FlacFrameParser.h

73 строки
2.3 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef FLAC_FRAME_PARSER_H_
#define FLAC_FRAME_PARSER_H_
#include "mozilla/Maybe.h"
#include "mozilla/Result.h"
#include "MediaDecoder.h" // For MetadataTags
#include "MediaInfo.h"
#include "MediaResource.h"
namespace mozilla {
#define FLAC_MAX_CHANNELS 8
#define FLAC_MIN_BLOCKSIZE 16
#define FLAC_MAX_BLOCKSIZE 65535
#define FLAC_MIN_FRAME_SIZE 11
#define FLAC_MAX_FRAME_HEADER_SIZE 16
#define FLAC_MAX_FRAME_SIZE \
(FLAC_MAX_FRAME_HEADER_SIZE + FLAC_MAX_BLOCKSIZE * FLAC_MAX_CHANNELS * 3)
class OpusParser;
// Decode a Flac Metadata block contained in either a ogg packet
// (https://xiph.org/flac/ogg_mapping.html) or in flac container
// (https://xiph.org/flac/format.html#frame_header)
class FlacFrameParser {
public:
FlacFrameParser();
~FlacFrameParser();
Result<bool, nsresult> IsHeaderBlock(const uint8_t* aPacket,
size_t aLength) const;
// Return the length of the block header (METADATA_BLOCK_HEADER+
// METADATA_BLOCK_DATA), aPacket must point to at least 4
// bytes and to a valid block header start (as determined by IsHeaderBlock).
uint32_t HeaderBlockLength(const uint8_t* aPacket) const;
Result<Ok, nsresult> DecodeHeaderBlock(const uint8_t* aPacket,
size_t aLength);
bool HasFullMetadata() const { return mFullMetadata; }
// Return the duration in frames found in the block. -1 if error
// such as invalid packet.
int64_t BlockDuration(const uint8_t* aPacket, size_t aLength) const;
// Return a hash table with tag metadata.
UniquePtr<MetadataTags> GetTags() const;
AudioInfo mInfo;
private:
bool ReconstructFlacGranulepos(void);
Maybe<uint32_t> mNumHeaders;
uint32_t mMinBlockSize;
uint32_t mMaxBlockSize;
uint32_t mMinFrameSize;
uint32_t mMaxFrameSize;
uint64_t mNumFrames;
bool mFullMetadata;
uint32_t mPacketCount;
// Used to decode the vorbis comment metadata.
UniquePtr<OpusParser> mParser;
};
} // namespace mozilla
#endif // FLAC_FRAME_PARSER_H_