HDMI Overview

Introduction

HDMI is a digital standard, which provides +an alternative to various analog standards like radio frequency (RF) +coaxial cable, composite video, component video, S-video (super video), +D-terminal (D-tanshi terminal) and VGA (video graphics array).

HDMI connects, using a single cable, a digital audio or video +source like a mobile phone, a set-top box, a blue-ray disc player, +or a PC to a compatible digital output device, for instance a computer +monitor, or a digital television.

In general HDMI supports +standard, enhanced, and high-definition (HD) video, and up to 6 channels +of digital audio, which provides the highest-quality home theater +experience. In Symbian^3 the HDMI features are based on HDMI 1.3a +software specifications for the device creator to adapt it to the +platform.

Purpose

HDMI provides communication between a mobile device and the HD +device. In Symbian^3 HDMI supports some functionality such as setting +and getting screen configuration information, which enables plug and +play without any need for configuration by the end user.

In +Symbian^3 HDMI supports the following features:

Maximum progressive +scan HD resolution of 1280 x 720 pixels. Progressive scan is a method +to display moving images.
Multi-channel +digital uncompressed audio data.
EDID (Extended +Display Identification Data). This is a data structure provided by +a computer display to describe its capabilities to a graphics card. +EDID is defined by a standard published by the Video Electronics Standards +Association (VESA).
HDCP (High-bandwidth +Digital Content Protection). This prevents copying audio and video +content. HDCP is invisible to the end-user unless a problem occurs. +If HDCP reports a problem an image related to DRM (Digital rights +management) failure and an error message are displayed, instead of +the video content and audio is muted.

In Symbian^3 the HDMI uses two modes such as non-HD (High Definition) +compliant view and HD compliant view. In Symbian^4 the +dual display mode will be implemented.

The HDMI modes are listed +below:

Clone mode or Non-HD compliant view
In this mode, +the mobile device and the HD display show the same information.
Native mode or HD compliant view
This mode takes +full advantage of HDMI, and reproduces mobile device content in the +maximum HD resolution available with HDMI. For example if a mobile +device displays a video clip, including its title and a progress bar, +the HD display might just show the video clip in full screen, (excluding +the others content).
Dual display mode
In this mode, the mobile devices's +display and the HD display are treated as separate displays by an +application like the photo gallery. The application controls what +is displayed in each.

The diagram +below shows the subsystems that need to be modified in order to adapt +HDMI in the Symbian platform by the device creator.

+HDMI architectural relationship with the subsystem + +

Application +layer
To use HDMI in an application no changes are required +in this layer. For example to play a video use the CVideoPlayerUtility2 API from the Video Client Library in the Multimedia framework (MMF).
Middleware +layer
To support high-definition resolutions, WMA (Windows +Media Audio) hardware device and multi-channel WMA to play video the Helix as the MMF controller plug-in is used.
OS Extension +layer
In order to play audio with support for HDCP use +the DevSound +library extension and the DRM APIs . +The Accessory +Server API provides the policy for audio routing.
OS layer +(Symbian)
To play video in HDMI mode use the Window Server to check the render stage policy of the graphics surface in the +video.
Adaptation +layer
For the audio adaptation use the CHdmiAudioLink API to play multi-channel audio. For the video adaptation use the CIveVideoDecodeVC1HwDevice API to play a video in fullscreen +and high resolution. The display driver is used to support display +modes like clone, dual and native modes. The system adaptation detects +HDMI protocols, and transfers the protocols to the HDMI driver.
HDMI driver
This driver transfers all data and initialization of the HDMI +chip from the adaptation layer to the hardware layer.
Hardware +layer
The HDMI chip is in the hardware layer. The chip is +used to receive and transmit the high performance video and audio +between the mobile device and the HDMI display.

Description

HDMI is used to implement the following use-cases:

Play video in full screen and high resolution.
Play audio with DRM supported.
View images including zooming and rotating in full screen.
Play audio with HDCP support to restricted audio output.

For example in order to play a video the following diagram +demonstrates the HDMI feature implementation:

+HDMI video play use-case + +

In order to play video the CVideoPlayerUtility2 API is used as the Video Client library, which plays sampled video data on graphics surfaces. In the MMF +layer, the RMMFController and the CHXNGAUtility APIs are used as the MMF controller framework, which initializes +the DevVideo API. The DevVideo uses the CMMFDevVideoPlay API +to play the video. The CIveVideoDecodeVC1HwDevice API provides video adaptation to the hardware layer. In the video +adaptation, a decision making engine chooses the graphics surface +on which to display the video on the HD display. The Window Server +API is used for dynamic resolution switching. The HDMI driver +transfers all video data to the HDMI chip, which is in the hardware +adaptation layer (the physical layer). The hardware layer transmits +video data to the HD display through a single cable.