BMediaBufferEncoder

Derived from: BMediaBufferEncoder
Mix-in classes: none
Declared in:  be/media/MediaEncoder.h
Library: libmedia.so
Summary:  more...

The BMediaBufferEncoder class, derived from BMediaBufferEncoder, can be used to encode media data from a memory buffer (instead of from a file).

It implements the BMediaBufferEncoder::WriteChunk() function to accomplish this task. BMediaBufferEncoder::AddTrackInfo() is not implemented.

Hook Functions

WriteChunk()

Constructor and Destructor

BMediaBufferEncoder()

BMediaBufferEncoder() BMediaBufferEncoder(const media_format *outputFormat) BMediaBufferEncoder(const media_codec_info *mci)

The constructor sets up the BMediaBufferEncoder. If you use the empty form of the constructor, you'll have to call SetTo() to establish the format to be encoded before calling encode().

The second form accepts a media_format structure, inFormat, that indicates the type of media data that will be input into the encoder.

The third form of the constructor accepts a media_codec_info structure, mci, that determines which codec should be used.

If you use either the media_format or media_codec_info form of the constructor, you must call InitCheck() to ensure that construction was successful before using any other functions in this class.

~BMediaBufferEncoder()

virtual ~BMediaBufferEncoder()

Releases the encoder add-on being used by the BMediaBufferEncoder.

Member Functions

EncodeToBuffer()

status_t EncodeToBuffer(void *outputBuffer, size_t *outputSize,       const void *inputBuffer, int64 frameCount,       media_encode_info *info)

Encodes a chunk of media data from the input buffer by inputBuffer, which contains frameCount frames of data. The encoded data is written into the buffer indicated by outputBuffer. On return, outputSize indicates how many bytes of data were written into the buffer.

The media_encode_info structure info is used on input to specify encoding parameters.

RETURN CODES

• B_OK. No error.

• Other errors. The encoder's Encode() function can return errors.

InitCheck()

status_t InitCheck(void) const

Returns a status_t value indicating whether or not construction was successful. You must call this function after construction before calling any other BMediaBufferEncoder functions.

RETURN CODES

• B_OK. The constructor was successful.

• SetTo() errors.

WriteChunk()

protected:

status_t WriteChunk(const void *chunkData, size_t chunkLength,       media_encode_info *info) = 0

Implemented to write the encoded media data into the buffer specified when EncodeToBuffer() was called.