srs/trunk/src/app/srs_app_flv.hpp

/*
The MIT License (MIT)

Copyright (c) 2013-2014 winlin

Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#ifndef SRS_APP_FLV_HPP
#define SRS_APP_FLV_HPP

/*
#include <srs_app_flv.hpp>
*/
#include <srs_core.hpp>

class SrsStream;

/**
* file stream to read/write file.
*/
class SrsFileStream
{
private:
    std::string _file;
    int fd;
public:
    SrsFileStream();
    virtual ~SrsFileStream();
public:
    virtual int open(std::string file);
    virtual int close();
    virtual bool is_open();
public:
    /**
    * @param pnread, return the read size. NULL to ignore.
    */
    virtual int read(void* buf, size_t count, ssize_t* pnread);
    /**
    * @param pnwrite, return the write size. NULL to ignore.
    */
    virtual int write(void* buf, size_t count, ssize_t* pnwrite);
    /**
    * tell current offset of stream.
    */
    virtual int64_t tellg();
};

/**
* encode data to flv file.
*/
class SrsFlvEncoder
{
private:
    SrsFileStream* _fs;
private:
    SrsStream* tag_stream;
public:
    SrsFlvEncoder();
    virtual ~SrsFlvEncoder();
public:
    /**
    * initialize the underlayer file stream,
    * user can initialize multiple times to encode multiple flv files.
    */
    virtual int initialize(SrsFileStream* fs);
public:
    /**
    * write flv header.
    * write following:
    *   1. E.2 The FLV header
    *   2. PreviousTagSize0 UI32 Always 0
    * that is, 9+4=13bytes.
    */
    virtual int write_header();
    /**
    * write flv metadata. 
    * serialize from:
    *   AMF0 string: onMetaData,
    *   AMF0 object: the metadata object.
    */
    virtual int write_metadata(char* data, int size);
    /**
    * write audio/video packet.
    */
    virtual int write_audio(int64_t timestamp, char* data, int size);
    virtual int write_video(int64_t timestamp, char* data, int size);
private:
    virtual int write_tag(char* header, int header_size, char* tag, int tag_size);
};

#endif