shaka-packager/packager/media/formats/mp4/mp4_media_parser.h

117 lines
3.5 KiB
C++

// Copyright 2014 Google LLC. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
#ifndef PACKAGER_MEDIA_FORMATS_MP4_MP4_MEDIA_PARSER_H_
#define PACKAGER_MEDIA_FORMATS_MP4_MP4_MEDIA_PARSER_H_
#include <cstdint>
#include <map>
#include <memory>
#include <vector>
#include <absl/flags/declare.h>
#include <absl/flags/flag.h>
#include <packager/macros/classes.h>
#include <packager/media/base/decryptor_source.h>
#include <packager/media/base/media_parser.h>
#include <packager/media/base/offset_byte_queue.h>
ABSL_DECLARE_FLAG(bool, use_dovi_supplemental_codecs);
namespace shaka {
namespace media {
namespace mp4 {
class BoxReader;
class TrackRunIterator;
struct Movie;
struct ProtectionSystemSpecificHeader;
class MP4MediaParser : public MediaParser {
public:
MP4MediaParser();
~MP4MediaParser() override;
/// @name MediaParser implementation overrides.
/// @{
void Init(const InitCB& init_cb,
const NewMediaSampleCB& new_media_sample_cb,
const NewTextSampleCB& new_text_sample_cb,
KeySource* decryption_key_source) override;
[[nodiscard]] bool Flush() override;
[[nodiscard]] bool Parse(const uint8_t* buf, int size) override;
/// @}
/// Handles ISO-BMFF containers which have the 'moov' box trailing the
/// movie data ('mdat'). It does this by doing a sparse parse of the file
/// to locate the 'moov' box, and parsing its contents if it is found to be
/// located after the 'mdat' box(es).
/// @param file_path is the path to the media file to be parsed.
/// @return true if successful, false otherwise.
bool LoadMoov(const std::string& file_path);
private:
enum State {
kWaitingForInit,
kParsingBoxes,
kEmittingSamples,
kError
};
bool ParseBox(bool* err);
bool ParseMoov(mp4::BoxReader* reader);
bool ParseMoof(mp4::BoxReader* reader);
bool FetchKeysIfNecessary(
const std::vector<ProtectionSystemSpecificHeader>& headers);
// To retain proper framing, each 'mdat' box must be read; to limit memory
// usage, the box's data needs to be discarded incrementally as frames are
// extracted from the stream. This function discards data from the stream up
// to |offset|, updating the |mdat_tail_| value so that framing can be
// retained after all 'mdat' information has been read.
// Returns 'true' on success, 'false' if there was an error.
bool ReadAndDiscardMDATsUntil(const int64_t offset);
void ChangeState(State new_state);
bool EmitConfigs();
bool EnqueueSample(bool* err);
void Reset();
State state_;
InitCB init_cb_;
NewMediaSampleCB new_sample_cb_;
KeySource* decryption_key_source_;
std::unique_ptr<DecryptorSource> decryptor_source_;
OffsetByteQueue queue_;
// These two parameters are only valid in the |kEmittingSegments| state.
//
// |moof_head_| is the offset of the start of the most recently parsed moof
// block. All byte offsets in sample information are relative to this offset,
// as mandated by the Media Source spec.
int64_t moof_head_;
// |mdat_tail_| is the stream offset of the end of the current 'mdat' box.
// Valid iff it is greater than the head of the queue.
int64_t mdat_tail_;
std::unique_ptr<Movie> moov_;
std::unique_ptr<TrackRunIterator> runs_;
DISALLOW_COPY_AND_ASSIGN(MP4MediaParser);
};
} // namespace mp4
} // namespace media
} // namespace shaka
#endif // PACKAGER_MEDIA_FORMATS_MP4_MP4_MEDIA_PARSER_H_