Audio Encoder

Detailed Description

Class: kodi::addon::CInstanceAudioEncoder

Audio encoder add-on instance.
For audio encoders as binary add-ons. This class implements a way to handle the encode of given stream to a new format.

The addon.xml defines the capabilities of this add-on.

---

Here's an example on addon.xml:

<extension
  point="kodi.audioencoder"
  extension=".flac"
  library_@PLATFORM@="@LIBRARY_FILENAME@"/>

Description to audio encoder related addon.xml values:

Name	Description
point	Addon type specification At all addon types and for this kind always "kodi.audioencoder".
library_@PLATFORM@	Sets the used library name, which is automatically set by cmake at addon build.
extension	The file extensions / styles supported by this addon.

---

---

Here is a code example how this addon is used:

#include <kodi/addon-instance/AudioEncoder.h>
 
class ATTR_DLL_LOCAL CMyAudioEncoder : public kodi::addon::CInstanceAudioEncoder
{
public:
  CMyAudioEncoder(const kodi::addon::IInstanceInfo& instance);
 
  bool Start(const kodi::addon::AudioEncoderInfoTag& tag) override;
  int Encode(int numBytesRead, const uint8_t* pbtStream) override;
  bool Finish() override; // Optional
};
 
CMyAudioEncoder::CMyAudioEncoder(const kodi::addon::IInstanceInfo& instance)
  : kodi::addon::CInstanceAudioEncoder(instance)
{
  ...
}
 
bool CMyAudioEncoder::Start(const kodi::addon::AudioEncoderInfoTag& tag)
{
  ...
  return true;
}
 
ssize_t CMyAudioEncoder::Encode(const uint8_t* pbtStream, size_t numBytesRead)
{
  uint8_t* data = nullptr;
  size_t length = 0;
  ...
  kodi::addon::CInstanceAudioEncoder::Write(data, length);
 
  return 0;
}
 
 
bool CMyAudioEncoder::Finish()
{
  ...
  return true;
}
 
//----------------------------------------------------------------------
 
class CMyAddon : public kodi::addon::CAddonBase
{
public:
  CMyAddon() = default;
  ADDON_STATUS CreateInstance(const kodi::addon::IInstanceInfo& instance,
                              KODI_ADDON_INSTANCE_HDL& hdl) override;
};
 
// If you use only one instance in your add-on, can be instanceType and
// instanceID ignored
ADDON_STATUS CMyAddon::CreateInstance(const kodi::addon::IInstanceInfo& instance,
                                      KODI_ADDON_INSTANCE_HDL& hdl)
{
  if (instance.IsType(ADDON_INSTANCE_AUDIOENCODER))
  {
    kodi::Log(ADDON_LOG_INFO, "Creating my audio encoder instance");
    hdl = new CMyAudioEncoder(instance);
    return ADDON_STATUS_OK;
  }
  else if (...)
  {
    ...
  }
  return ADDON_STATUS_UNKNOWN;
}
 
ADDONCREATOR(CMyAddon)

The destruction of the example class CMyAudioEncoder is called from Kodi's header. Manually deleting the add-on instance is not required.

Function Documentation

CInstanceAudioEncoder()

CInstanceAudioEncoder ( const kodi::addon::IInstanceInfo & instance )

inlineexplicit

Audio encoder class constructor used to support multiple instances.

Parameters

[in]

instance

The instance value given to kodi::addon::CAddonBase::CreateInstance(...).

---

Here's example about the use of this:

class CMyAudioEncoder : public kodi::addon::CInstanceAudioEncoder
{
public:
  CMyAudioEncoder(const kodi::addon::IInstanceInfo& instance)
    : kodi::addon::CInstanceAudioEncoder(instance)
  {
     ...
  }
 
  ...
};
 
ADDON_STATUS CMyAddon::CreateInstance(const kodi::addon::IInstanceInfo& instance,
                                      KODI_ADDON_INSTANCE_HDL& hdl)
{
  kodi::Log(ADDON_LOG_INFO, "Creating my audio encoder instance");
  hdl = new CMyAudioEncoder(instance);
  return ADDON_STATUS_OK;
}

Start()

virtual bool Start ( const kodi::addon::AudioEncoderInfoTag & tag )

pure virtual

Start encoder (required)

Parameters

[in]

tag

Information tag about

Returns

True on success, false on failure.

Encode()

virtual ssize_t Encode ( const uint8_t * pbtStream, size_t numBytesRead )

pure virtual

Encode a chunk of audio (required)

Parameters

[in]	pbtStream	The input buffer
[in]	numBytesRead	Number of bytes in input buffer

Returns

Number of bytes consumed

Finish()

virtual bool Finish ( )

inlinevirtual

Finalize encoding (optional)

Returns

True on success, false on failure.

Write()

ssize_t Write ( const uint8_t * data, size_t length )

inline

Write block of data.

Parameters

[in]	data	Pointer to the array of elements to be written
[in]	length	Size in bytes to be written.

Returns

The total number of bytes successfully written is returned.

Remarks

Only called from addon itself.

Seek()

ssize_t Seek ( ssize_t position, int whence = SEEK_SET )

inline

Set the file's current position.

The whence argument is optional and defaults to SEEK_SET (0)

Parameters

[in]	position	The position that you want to seek to
[in]	whence	[optional] offset relative to You can set the value of whence to one of three things: Value int Description SEEK_SET 0 position is relative to the beginning of the file. This is probably what you had in mind anyway, and is the most commonly used value for whence. SEEK_CUR 1 position is relative to the current file pointer position. So, in effect, you can say, "Move to my current position plus 30 bytes," or, "move to my current position minus 20 bytes." SEEK_END 2 position is relative to the end of the file. Just like SEEK_SET except from the other end of the file. Be sure to use negative values for offset if you want to back up from the end of the file, instead of going past the end into oblivion.

Returns

Returns the resulting offset location as measured in bytes from the beginning of the file. On error, the value -1 is returned.

Remarks

Only called from addon itself.