Migration from Native Client to WebAssembly

This section provides an extension to https://developer.chrome.com/docs/native-client/migration/ article, which describes interface mapping from Google PPAPI interfaces to WebAssembly.

Emscripten SDK, modified by Samsung, provides additional functionalities that were available in Native Client - Player, Sockets and Video Decoder APIs.

This topic lists all the Samsung-specific PPAPIs and their corresponding WASM APIs, for ease of reference when planning your WebAssembly application project.

Samsung-specific PPAPIs vs. WASM

The following table contains all the Samsung specific PPAPIs and their WebAssembly (WASM) equivalents in the Samsung Emscripten SDK.

	PPAPI	WASM
Player	NaCl Player	WASM Player
Sockets	POSIX API (through nacl_io)	POSIX API
Video Decoder	pp::VideoDecoder	Part of WASM Player functionality. WASM Player needs to be initialized with the RenderingMode::kVideoTexture parameter, which indicates that you want to return decoded frames to application as GL Texture instead of presenting them on a screen.

Table 1. Samsung PPAPIs and Their WASM Equivalents

Data Source Functionalities

The following table shows how the WASM Player supports the Samsung::NaClPlayer::ESDataSource functionalities.

PPAPI	Corresponding WASM API
Samsung::NaClPlayer::ESDataSource::AddStream	samsung::wasm::ElementaryMediaStreamSource::AddTrack
Samsung::NaClPlayer::ESDataSource::SetDuration	samsung::wasm::ElementaryMediaStreamSource::SetDuration
Samsung::NaClPlayer::ESDataSource::SetEndOfStream	samsung::wasm::ElementaryMediaTrack::AppendEndOfTrack

Table 2. Data Source Methods

Elementary Stream Functionalities

The following table shows how the WASM Player supports the Samsung::NaClPlayer::ElementaryStream functionalities.

PPAPI	Corresponding WASM API
Samsung::NaClPlayer::ElementaryStream::GetStreamType	samsung::wasm::ElementaryMediaTrack::GetType
Samsung::NaClPlayer::ElementaryStream::InitializeDone	samsung::wasm::ElementaryMediaStreamSource::AddTrack
Samsung::NaClPlayer::ElementaryStream::AppendPacket	samsung::wasm::ElementaryMediaTrack::AppendPacketAsync
Samsung::NaClPlayer::ElementaryStream::AppendEncryptedPacket	samsung::wasm::ElementaryMediaTrack::AppendEncryptedPacketAsync
Samsung::NaClPlayer::ElementaryStream::AppendTrustZonePacket	No corresponding WASM API available
Samsung::NaClPlayer::ElementaryStream::Flush	samsung::wasm::ElementaryMediaStreamSource::Flush
Samsung::NaClPlayer::ElementaryStream::SetDRMInitData	samsung::wasm::MediaKey::SetupEncryption

Table 3. Elementary Stream Methods

Audio Elementary Stream Functionalities

The following table shows how the WASM Player supports the Samsung::NaClPlayer::AudioElementaryStream functionalities.

PPAPI	Corresponding WASM API
Samsung::NaClPlayer::AudioElementaryStream::GetAudioCodecType	samsung::wasm::ElementaryMediaTrackConfig::mime_type
Samsung::NaClPlayer::AudioElementaryStream::SetAudioCodecType	samsung::wasm::ElementaryMediaTrackConfig::mime_type
Samsung::NaClPlayer::AudioElementaryStream::GetAudioCodecProfile	samsung::wasm::ElementaryMediaTrackConfig::mime_type
Samsung::NaClPlayer::AudioElementaryStream::SetAudioCodecProfile	samsung::wasm::ElementaryMediaTrackConfig::mime_type
Samsung::NaClPlayer::AudioElementaryStream::GetSampleFormat	samsung::wasm::ElementaryAudioTrackConfig::sample_format
Samsung::NaClPlayer::AudioElementaryStream::SetSampleFormat	samsung::wasm::ElementaryAudioTrackConfig::sample_format
Samsung::NaClPlayer::AudioElementaryStream::SetBitsPerChannel	No corresponding WASM API available
Samsung::NaClPlayer::AudioElementaryStream::GetBitsPerChannel	No corresponding WASM API available
Samsung::NaClPlayer::AudioElementaryStream::GetSamplesPerSecond	samsung::wasm::ElementaryAudioTrackConfig::samples_per_second
Samsung::NaClPlayer::AudioElementaryStream::GetBitsPerChannel	samsung::wasm::ElementaryAudioTrackConfig::samples_per_second
Samsung::NaClPlayer::AudioElementaryStream::SetCodecExtraData	samsung::wasm::ElementaryMediaTrackConfig::extradata

Table 4. Audio Elementary Stream Methods

Video Elementary Stream Functionalities

The following table shows how the WASM Player supports the Samsung::NaClPlayer::VideoElementaryStream functionalities.

PPAPI	Corresponding WASM API
Samsung::NaClPlayer::VideoElementaryStream::GetVideoCodecType	samsung::wasm::ElementaryMediaTrackConfig::mime_type
Samsung::NaClPlayer::VideoElementaryStream::SetVideoCodecType	samsung::wasm::ElementaryMediaTrackConfig::mime_type
Samsung::NaClPlayer::VideoElementaryStream::GetVideoCodecProfile	samsung::wasm::ElementaryMediaTrackConfig::mime_type
Samsung::NaClPlayer::VideoElementaryStream::SetVideoCodecProfile	samsung::wasm::ElementaryMediaTrackConfig::mime_type
Samsung::NaClPlayer::VideoElementaryStream::GetVideoFrameFormat	No corresponding WASM API available
Samsung::NaClPlayer::VideoElementaryStream::SetVideoFrameFormat	No corresponding WASM API available
Samsung::NaClPlayer::VideoElementaryStream::GetVideoFrameSize	samsung::wasm::ElementaryVideoTrackConfig::width samsung::wasm::ElementaryVideoTrackConfig::height
Samsung::NaClPlayer::VideoElementaryStream::SetVideoFrameSize	samsung::wasm::ElementaryVideoTrackConfig::width samsung::wasm::ElementaryVideoTrackConfig::height
Samsung::NaClPlayer::VideoElementaryStream::GetFrameRate	samsung::wasm::ElementaryVideoTrackConfig::framerate_num samsung::wasm::ElementaryVideoTrackConfig::framerate_den
Samsung::NaClPlayer::VideoElementaryStream::SetFrameRate	samsung::wasm::ElementaryVideoTrackConfig::framerate_num samsung::wasm::ElementaryVideoTrackConfig::framerate_den
Samsung::NaClPlayer::VideoElementaryStream::SetCodecExtraData	samsung::wasm::ElementaryMediaTrackConfig::extradata

Table 5. Video Elementary Stream Methods

Media Player Functionalities

The following table shows how the WASM Player supports the Samsung::NaClPlayer::MediaPlayer functionalities.

PPAPI	Corresponding WASM API
Samsung::NaClPlayer::MediaPlayer::MediaPlayer	samsung::wasm::HtmlMediaElement
Samsung::NaClPlayer::MediaPlayer::SetMediaEventsListener	samsung::html::HtmlMediaElement::SetListener
Samsung::NaClPlayer::MediaPlayer::SetSubtitleListener	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::SetBufferingListener	samsung::html::HtmlMediaElement::SetListener
Samsung::NaClPlayer::MediaPlayer::SetDRMListener	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::BindToDisplay	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::AttachDataSource	samsung::html::HTMLMediaElement::SetSrc
Samsung::NaClPlayer::MediaPlayer::Play	samsung::html::HTMLMediaElement::Play
Samsung::NaClPlayer::MediaPlayer::Pause	samsung::html::HTMLMediaElement::Pause
Samsung::NaClPlayer::MediaPlayer::Stop	samsung::html::HTMLMediaElement::~HTMLMediaElement
Samsung::NaClPlayer::MediaPlayer::Seek	samsung::html::HTMLMediaElement::SetCurrentTime
Samsung::NaClPlayer::MediaPlayer::SetPlaybackRate	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::GetDuration	samsung::html::HTMLMediaElement::GetDuration
Samsung::NaClPlayer::MediaPlayer::GetCurrentTime	samsung::html::HTMLMediaElement::GetCurrentTime
Samsung::NaClPlayer::MediaPlayer::GetPlayerState	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::GetCurrentVideoTrackInfo	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::GetVideoTracksList	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::GetCurrentAudioTrackInfo	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::GetAudioTracksList	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::GetCurrentTextTrackInfo	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::GetTextTracksList	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::SelectTrack	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::AddExternalSubtitles	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::SetSubtitlesDelay	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::SetDisplayRect	Customized with video-tag parameters in JavaScript
Samsung::NaClPlayer::MediaPlayer::SetDisplayMode	Customized with video-tag parameters in JavaScript
Samsung::NaClPlayer::MediaPlayer::SetVr360Mode	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::SetVr360Rotation	No corresponding WASM API available
Samsung::NaClPlayer::MediaPlayer::SetDRMSpecificData	samsung::wasm::MediaKey::SetupEncryption

Table 6. Media Player Methods

URL Data Source Functionalities

The following table shows how the WASM Player supports the Samsung::NaClPlayer::URLDataSource functionalities.

PPAPI	WASM (Emscripten)
Samsung::NaClPlayer::URLDataSource	Available using video tag with url src element.

Table 7. URL Data Source Methods

Video Decoder Functionalities

The following table shows how the WASM Player supports the pp::VideoDecoder functionalities.

PPAPI	WASM (Emscripten)
pp::VideoDecoder::Create	samsung::wasm::ElementaryMediaStreamSource::AddTrack
pp::VideoDecoder::Initialize	samsung::wasm::ElementaryMediaStreamSource::AddTrack
pp::VideoDecoder::Decode	samsung::html::HtmlMediaElement::Play
pp::VideoDecoder::GetPicture	samsung::wasm::ElementaryMediaTrack::FillTextureWithNextFrame
pp::VideoDecoder::RecyclePicture	samsung::wasm::ElementaryMediaTrack::RecycleTexture
pp::VideoDecoder::Flush	samsung::wasm::ElementaryMediaStreamSource::Flush
pp::VideoDecoder::Reset	samsung::wasm::ElementaryMediaStreamSource::RemoveTrack samsung::wasm::ElementaryMediaStreamSource::AddTrack

Table 8. Video Decoder Methods