Chromecast

from Wikipedia, the free encyclopedia
Chromecast
Manufacturer Google LLC
category Streaming box
Initial release July 24, 2013
Power supply Micro USB port
SoC 1st generation Marvell 88DE3005-A1
2nd generation SoC Marvell 88DE3006
Dimensions 72 mm × 35 mm × 12 mm
Weight 34 g
predecessor Nexus Q

Chromecast is the name of several types of streaming media adapters offered by the US company Google LLC that work on the basis of the Google Cast protocol .

functionality

The device is connected to an AV playback device (e.g. television ) via HDMI or audio interface and transmits (“streams”) audio and video via WLAN . The power is supplied via a USB cable either from the power supply unit supplied or from another device that provides the + 5V DC voltage common for USB with sufficient current . The user can transfer content from supported apps as well as using “Google Cast for Chrome” from the desktop browser Google Chrome to an AV playback device. The user controls the selection of media (videos, audio files, photos) and their playback behavior via the Chromecast-compatible apps. Special software (app) must be installed on the controlling device (currently: Google Home ), which is offered by Google for the mobile operating systems Android and iOS . Controlled in this way, the Chromecast receives media streams from the wireless access point , decodes them and forwards the content to the AV playback device. During playback, other tasks can be carried out on the controlling Android device, such as answering phone calls . The content processed by the Chromecast can come from the Internet, the local area network (LAN) or the controlling computer or mobile device. For example, you can mirror a tab from the Chrome desktop browser, the entire screen content (on a PC or a mobile device) or view locally stored video, audio and photo files. There are also applications to e.g. B. to display a quiz with four answer options, and apps that use the control unit as a graphics tablet on which the user can draw with his finger while the result is displayed on the television or monitor.

If nothing is currently being played, the start screen ("Homescreen") appears which, in addition to the time and name of the Chromecast, also displays screensavers (landscape images) that fill the screen and that change periodically. The Chromecast is set up and configured for the first time using the Google Home app (former name: Chromecast app or Google Cast app), and it can also be used to control the Chromecast's volume. With version 1.8.22 of the Chromecast app in October 2014, the "backdrop" function was added to adapt the media and information displayed on the stick. For example, you can incorporate your own photos, display the local weather, and display art paintings, news and satellite images. "Google uses in-house services such as the Art Project , Maps and Google Plus ."

Streaming architecture

Connected Chromecast HDMI stick of the first generation

The streaming architecture Google Home (until October 2016 Google Cast ) regulates the communication from sender to receiver in mobile devices. From the control unit, e.g. For example, a tablet or smartphone, only URLs and control data (e.g. pause, volume change) are transferred to the stick as “commands” (except for offline content). This gets the source via the WLAN connection from the Internet or the local network. The transmission of any screen content or different applications at the same time is not possible. In the strict sense, it is not a streaming protocol. From a technical point of view, it is not in direct competition with streaming protocols such as Miracast or Apple AirPlay . Technically, the protocol can be compared with DLNA . Google Cast is based on the multicast DNS protocol. In older versions the protocol DIAL (Discover And Launch Protocol) was used, which used the UPnP procedure .

advantages

  • The energy consumption in the control unit is lower compared to Miracast or Apple AirPlay, as only control data and not the entire screen content is transmitted. This only applies to media content in the cloud or on supported online services.
  • A screen transfer function ( screen mirroring ) is available with Android devices from version 4.4.2.
  • Since it is controlled by the mobile device or computer, no additional remote control is required. If the respective service supports it, several devices can control the data transmission one after the other or at the same time. Family members can add songs or videos to a playlist.
  • The playback is independent of the control device with which the playback was initiated. Playback continues even if the battery in the mobile device is discharged or if it is out of Wi-Fi range.
  • Compared to a transmission according to the Wi-Fi Direct standard , the mobile device's Internet connection is not disconnected.
  • There are no costs after purchasing the Chromecast device (except, if applicable, costs for the services used and internet access).

Disadvantages or criticism

  • At first it was not possible to transfer content directly from the mobile device (e.g. photos) to the television. Content first had to be uploaded to the cloud, e.g. B. via Google+. Since December 2013, this has been made possible by third-party applications, e.g. B. Avia or Plex , and many other applications since the Chromecast SDK was released.
  • The stick will not work without an internet connection, even if you only want to play local media.
  • If the power is supplied via the supplied power supply unit, the stick always consumes power. It therefore makes sense to use a live USB connection on the television set, provided that it is not also supplied with electricity in standby mode. Alternatively, there are master-slave sockets .
  • With the exception of Chromecast Ultra , playback in 4K is not possible (not even with Netflix ), as the Chromecast output only supports HDMI 1.x and not HDMI 2.0 and thus the bandwidth for 4K resolution and 60 frames / s is too small ; Adapters to the standard DisplayPort 1.3 do not help.

Transfer of tabs from the Google Chrome browser

Action icon in apps that is used to connect to, control and disconnect Google Home receivers.

In addition to the streaming architecture, Chromecast supports the transfer of open tabs from Google Chrome to another device ( Tab Cast ). The content is transferred directly from the computer to Chromecast (similar to Miracast or Apple AirPlay) with the associated restrictions such as higher energy consumption and device-dependent playback. Local content can also be transferred via Tab Cast . The following restrictions apply when using the function:

  • So far only the desktop version of Chrome is supported, a transfer from mobile devices is not possible.
  • The transmission is of a lower quality than applications directly supported by the streaming architecture and depends on the computer used. The maximum supported resolution is 720p .

In addition to transferring a single tab, there is the option of mirroring the entire screen content of a computer. This can be activated in the Chrome browser via the streaming menu using the “Stream desktop” option. Other programs and the entire system interface are also transferred. Audio is only transmitted from computers with Windows, macOS and Chrome OS are not supported.

Apps and games

Supported apps were initially YouTube , Netflix without 4K, Google Play and, since December 10, 2013, Songza, Vevo , Plex , Red Bull.TV, Revision 3, PostTV, Viki, BeyondPod, RealPlayer Cloud and Avia. The video-on-demand portal Watchever was available as an app when it was launched in Germany on March 19, 2014 until the service was discontinued at the end of 2016 .

On February 4, 2014, Google released the Chromecast SDK development interface, which can be used to develop Chromecast-compatible apps. The requirement for this is the Google Cast SDK Developer Console , which costs 5 euros. Since then, there have also been free applications for transferring offline content. The first and best known is the AllCast app by Koushik Dutta, who is best known for the alternative custom ROM CyanogenMod .

The Cast Store app , which provides an unofficial overview of Android apps with Chromecast support, now lists several hundred apps and a few games.

The games usually include simple applications in terms of operation, for example a multiplayer quiz or tic-tac-toe , which transmit questions and answers or the playing field to the television. Using screen mirroring , however, more complex surfaces are also conceivable; the developer platform Rolocule uses this as well as the motion sensors of the control unit to use it as a controller. This technology is very similar to game consoles such as Nintendo Wii or Xbox Kinect . A tennis application acts as a demo app, and more are to follow - other programmers can also use the technology used and develop such games.

Launch

The device was sold in the United States on July 24, 2013 and in 11 other countries, including Germany, since March 19, 2014.

hardware

First generation

Chromecast 1st generation

The first generation of the Chromecast, released on July 23, 2013, is based on the System-on-a-Chip 88DE3005-A1 (marketing name: Armada 1500 Mini ) from the Bermudian manufacturer Marvell . The SoC is equipped with a single-core Cortex-A9 CPU, which is probably clocked with ~ 800 MHz. It enables the decoding of the video compression formats VP8 and H.264 via hardware-supported codecs . Wireless communication takes place via the AzureWave NH-387 radio module (based on the Marvell SoC 88W8787), which enables WLAN in accordance with the IEEE 802.11 b / g / n standard in the 2.4 GHz band. The first generation of the Chromecast has 512 MB DDR3-SDRAM (DDR3L) and 2 GB flash memory , both memories are not expandable. The device has a first-generation HDMI connection for connection to an HDMI-compatible display device and a micro-USB connection, which is used to supply power to the HDMI stick . There is an LED on the device to display the operating status and a button to reset the Chromecast. A remote control is not included, as a computer, smartphone or tablet computer with suitable software is required for operation .

The model number H2G2-42 is a reference to the novel The Hitchhiker's Guide to the Galaxy (Original title: The Hitchhiker's Guide to the Galaxy ) H2G2 abbreviated, and occurring in definition of the number 42 in response to the "Ultimate Question of Life, the Universe and all the rest ”. The supplied power adapter has the model number MST3K-US, which is a reference to the American television series Mystery Science Theater 3000 (MST3K).

Second generation

Chromecast 2nd generation (above) and Chromecast Audio (below)

The second Chromecast generation, which has been available since September 29, 2015, is based on the SoC Marvell 88DE3006 (marketing name: Armada 1500 Mini Plus ), which has a dual-core Cortex-A7 CPU with 1.2 GHz clock frequency. The second generation also stands out due to its significantly changed appearance. Chromecast is now disc-shaped, similar to an ice hockey puck . It is connected to the television using a short integrated HDMI cable. The cable is flexible and can be magnetically attached to the device to offer more options for positioning behind the TV. The second generation has an improved wireless module (based on the Marvell SoC 88W8887), which offers support for 802.11ac and 5 GHz bands. Also new are three adaptive antennas inside the Chromecast, which should ensure better signal quality between the Chromecast and the wireless access point. The device has 512 MB main memory and 256 MB flash memory.

The model number NC2-6A5 of the second Chromecast generation is a tribute to the USS Enterprise NCC-1701 from Star Trek . The "NC2" can also be read as "NCC", while the hexadecimal number "6A5 " corresponds to "1701" in the decimal system .

The second generation can be recognized by the Chrome logo on the device.

Chromecast Audio

With the introduction of the second Chromecast generation, Chromecast Audio also appeared as a variant that is only designed for audio transmission. The dimensions and optics of the audio version are identical to those of the Chromecast 2, with the difference that an embossed groove on the top symbolizes a record. Using a 3.5 mm jack plug or a digital TOSLINK cable (with an additional adapter), Chromecast Audio can be connected to a speaker system or a stereo system and is connected to a playback device such as a smartphone or tablet via WiFi. Power is supplied via the power supply unit supplied, which is connected to the device via a micro USB plug.

The model number of your Chromecast Audio is RUX J42 and was isolated as an allusion to the debut album Are You Experienced by Jimi Hendrix interpreted. While "RUX" can be read as an abbreviation for the album title, "J42" indicates Hendrix's first name and the year he was born in 1942. However, there is no evidence to support this assumption.

In January 2019, Google announced that the production of the Chromecast Audio has been discontinued and only remnants will be sold. As a justification, Google stated that it now has "a variety of products with which users can enjoy audio".

LAN adapter

Using an optionally available LAN adapter, the Chromecast device can also be operated independently of the WLAN via network cable, which in many cases benefits stability and speed. The USB input is not only used for the power supply, but also for the network connection. A power supply via another USB source (e.g. television) is then no longer possible.

Chromecast Ultra

On October 4, 2016, Google introduced Chromecast Ultra , which appeared in November 2016 and is offered in addition to the previous generation. Chromecast Ultra supports streaming of 4K UHD and HDR content. Visually, the Chromecast Ultra is similar to the second generation, but is slightly larger in size. The scope of delivery includes a power supply unit with an integrated LAN connection so that the device can also be operated without WLAN.

Third generation

As of October 9, 2018, the third generation Chromecast was offered for sale in the US store. In Germany it was available in stores from October 24, 2018, in Switzerland from January 22, 2019. The Chromecast is similar to the second generation in terms of shape and dimensions, and Bluetooth was also installed. The third generation can be recognized by the letter "G" in the middle of the case.

Model overview

model 1st generation 2nd generation Chromecast Audio Chromecast Ultra Chromecast 3
publication July 24, 2013 29th September 2015 November 6, 2016 October 24, 2018
Introductory price € 39.99 € 79.99 € 39.00
System-on-a-chip Marvell Armada 1500 Mini 88DE3005-A1 Marvell Armada 1500 Mini Plus 88DE3006
random access memory 512 MB RAM DDR3L 256 MB RAM DDR3L
Internal memory 2 GB 256 MB
output 1080p - 4K Ultra HD
High Dynamic Range ( HDR10 , Dolby Vision ) 		1080p @ 60 FPS
Audio DAU - AKM AK4430 192kHz 24-bit DAC - -
connections HDMI ( CEC support) 3.5 mm connector with analog and
optical digital audio output 		HDMI (CEC support) HDMI (CEC support)
network 2.4 GHz WLAN ( 802.11 b / g / n)
Ethernet (with optionally available adapter) 		2.4 and 5 GHz WLAN ( 802.11 b / g / n / ac)
Ethernet (with optionally available adapter) 		2.4 and 5 GHz WLAN ( 802.11 b / g / n / ac)
Ethernet (with optionally available adapter)
Bluetooth
Power supply Micro USB cable
Dimensions 72 mm × 35 mm × 12 mm 51.8 mm × 51.8 mm × 13.5 mm 58.2 mm × 58.2 mm × 13.7 mm 51.9 mm × 51.9 mm × 13.8 mm
Weight 34 g 39.1 g 30.7 g 47 g 40 g

software

operating system

At the press conference on the introduction of Chromecast, Hugo Barra, who was then vice president of Android product development at Google, said that Chromecast was running a “simplified version of Chrome OS”. A group of hackers later reported that the device was "more Android than Chrome OS" and was derived from software (based on the Android operating system) embedded in Google TV . As with Chrome OS devices, firmware updates are automatically downloaded and installed without notifying or asking the user.

Format support

Chromecast supports various media formats; they are displayed in special sites as a receiver ( receiver are referred to).

The supported image formats include BMP, GIF, JPEG, PNG and WebP with a resolution of up to 1280 by 720 pixels (720p); larger image formats are scaled down. HE-AAC , AAC LC, MP3 , Ogg Vorbis and Wave LPCM are supported as audio formats . Audio data encoded in Dolby Digital and Dolby Digital Plus are "looped through" via HDMI (audio pass-through) and can be decoded by suitable end devices such as AV receivers ; however, other audio formats popular in home theater such as DTS , DTS-HD Master Audio or Dolby TrueHD are not supported. The video formats processed by Chromecast include H.264 High Profile Level 4.1 (in the resolutions 720p / 60 and 1080p / 30) and VP8; The video containers MP4, WebM and various subtitle variants are supported: Timed Text Markup Language (TTML), Web Video Text Tracks ( WebVTT ) and the CEA-608 standard.

The Media Player Library (MPL) used by the Chromecast supports streaming protocols with adaptive bit rates to adjust the playback quality in relation to the bandwidth as well as the progressive downloading of videos; It is also possible to integrate your own component for playback. Unlike the Android operating system, Chromecast supports numerous bit rate adaptive formats, including the necessary CORS support , as well as digital rights management (DRM): this includes MPEG-DASH with PlayReady (Security Level 2000) and Widevine (Level 1), SmoothStreaming with PlayReady (Security Level 2000) and Apple's proprietary HLS including AES encryption with 128 bit.

Alternatively, it is possible to download and display video data progressively.

Device discovery protocol

Chromecast uses multicast DNS to find active cast-enabled devices in the current network, also known as device discovery ; this has been the standard procedure since version 2 of the Google Cast SDK was introduced.

Version 1 of the Google Cast SDK, now obsolete, used the DIscovery And Launch protocol (DIAL over SSDP), which was created in the collaboration between Netflix and YouTube and uses the Simple Service Discovery Protocol (SSDP) from Universal Plug and Play .

The later introduced guest mode enables users to connect to the Chromecast without having to be logged into the network in which the Chromecast is located. If guest mode is activated, the Chromecast sends out a special WLAN signal ( beacon ). If a guest device receives this signal and tries to establish a connection with the Chromecast, it generates a four-digit code (PIN) and displays it on the start screen; In addition, the Chromecast generates ultrasound tones that are inaudible to humans via the playback device. These are used for automatic registration, provided that the guest device to be registered can receive them via the built-in microphone. Alternatively, the PIN code can also be entered manually.

Guest mode requires an Android device from Android 4.3 or an iOS device from version 7.0 and the latest Chromecast firmware.

Supported devices for operation

To operate the Chromecast, you need a computer, smartphone or tablet computer in the same network (or in guest mode) with suitable software. Independent use, for example via a remote control or Bluetooth keyboard, is not provided.

One of the following operating systems with installed Google Chrome browser is required on desktop and laptop computers :

Control with a smartphone or tablet computer is only possible on Android and Apple iOS- based devices:

  • Android version 4.1 or higher,
  • Apple iOS from version 8.0.

To set up the Chromecast and to use the guest mode (only on Android 4.3 or newer), the Google Home app, at that time the Chromecast app ", is required in the latest version.

See also

Web links

Commons : Chromecast  - collection of pictures, videos and audio files

Individual evidence

  1. ↑ Google Unveils $ 35 Chromecast HDMI TV Stick . Cnx-software.com. Retrieved July 26, 2013.
  2. ↑ Chromecast update: backdrop function enables customization. October 12, 2014, accessed November 8, 2014 .
  3. ↑ Google developer page for Google Cast API , accessed August 29, 2013.
  4. ↑ Google Chromecast - Another Streaming Architecture , article by Heise Verlag on the Chromecast streaming architecture, accessed on August 29, 2013.
  5. ↑ admin74: How Chromecast Works, Chromecast Protocol Described . In: Computer Solution . Computer Solution. July 28, 2013. Archived from the original on October 6, 2013. Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved August 13, 2013. @1@ 2Template: Webachiv / IABot / computers-solution.com
  6. ↑ Google Play Store page for the Avia application , accessed on January 8, 2014.
  7. ↑ a b Moritz Stückler: 10 new apps with Google Chromecast support - including Plex. ( Memento of the original from December 13, 2013 in the Internet Archive ) Info: The archive link was automatically inserted and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. In: T3n.de . December 10, 2013, accessed December 11, 2013. @1@ 2Template: Webachiv / IABot / t3n.de
  8. ↑ xda-developers.com: How to directly cast from android device in tethering WiFi AP mode. December 2, 2014, accessed December 2, 2014 .
  9. ↑ Google Cast Design Checklist . In: Google Developers . Google. Retrieved July 30, 2014.
  10. ↑ Ryan Whitwam: Chromecast tab casting: How to stream your desktop, browser, and local media to your TV (video) . English. Online at extremetech.com on July 29, 2013, accessed September 3, 2013.
  11. ↑ System requirements for the Google Cast Extension , accessed on August 30, 2013
  12. ↑ ChromeCast Optimized Playback vs. Casting a Tab , Help for Casting Tab, support.google.com, accessed August 30, 2013.
  13. ↑ Supported devices - Google Chromecast ( Memento of the original from March 19, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , Watchever.de, accessed on March 19, 2014. @1@ 2Template: Webachiv / IABot / www.watchever.de
  14. ↑ www.zdnet.de/88183127/google-oeffnet-chromecast-sdk-fuer-alle-entwickler .
  15. ↑ Google Play Store page for the Cast Store application
  16. ↑ Google Play Store page for the TicTacToe for Chromecast application
  17. ↑ Stefan Kirchner: Rolocule: Google's Chromecast as a game console. In: androidtv. July 4, 2014, accessed July 5, 2014 .
  18. ↑ Henning Steier: $ 35 back door to the television , nzz.ch of July 24, 2013.
  19. ↑ a b Ryan Smith: Google's Chromecast 2 is Powered By Marvell's ARMADA 1500 Mini Plus - Dual-Core Cortex-A7 . In: Anandtech.com . October 5, 2015. Retrieved October 7, 2015.
  20. ↑ a b Chromecast teardown . In: iFixit . Retrieved October 24, 2013.
  21. ↑ Kevin Parrish: FCC Reveals Google Chromecast Hardware and More . In: Tom's Hardware . July 25, 2013. Retrieved October 24, 2013.
  22. ^ The Hitchhiker's Guide to the Chromecast . In: Google Operating System . July 29, 2013. Retrieved October 24, 2013.
  23. ↑ Scott Lowe: Google Chromecast's Geeky Easter Eggs . In: UK.IGN.com . July 30, 2013. Retrieved June 26, 2014.
  24. ↑ a b Dismantling and information on the components , ifixit.com, accessed on November 19, 2015
  25. ↑ Taylor Kerns: Google confirms Chromecast Audio has been discontinued - get 'em at a discount while you can. In: Android Police. January 11, 2019, accessed on January 14, 2019 .
  26. ↑ Carsten Knobloch: Google Chromecast Audio is discontinued. In: Caschy's blog. January 11, 2019, accessed January 11, 2019 .
  27. ↑ Chromecast Ultra offers 4K and a network connection . In: Golem.de . October 4, 2016. Retrieved October 28, 2016.
  28. ↑ Marie Black: Google's Chromecast 3 is available to buy now. Retrieved January 3, 2019 .
  29. ↑ Tobias Weidemann: Chromecast: Google's new streaming dongle soon also in Germany. Retrieved January 3, 2019 .
  30. ↑ Finally: The new Chromecast from Google can be bought from today in Switzerland. In: Techgarage. January 22, 2019, accessed on January 22, 2019 (Swiss Standard German).
  31. ↑ Nexus 7 and Chromecast Press Event - 7/24/13 . In: YouTube . Google. Retrieved July 31, 2013.
  32. ↑ Chromecast: Exploiting the Newest Device By Google. . In: GTV Hacker . July 28, 2013. Retrieved July 31, 2013.
  33. ^ Matt Brian: Google's Chromecast has its roots in Android, not Chrome OS . In: The Verge . Vox Media. July 28, 2013. Retrieved July 31, 2013.
  34. ↑ Ambarish Kenghe: Chrome Releases: Chromecast Update . In: Googlechromereleases.blogspot.com . Google. July 31, 2013. Retrieved August 27, 2013.
  35. ↑ Supported Media for Google Cast
  36. ↑ Multicast DNS
  37. ↑ Ali Naddaf: Google Cast Developers (Chromecast developer post) . In: Google+ . Google. May 1, 2014.
  38. ↑ Discovery and Launch
  39. ↑ Sean Hollister: Like Chromecast, Roku wants to let you launch TV apps from your phone or tablet . In: The Verge . Vox Media. September 13, 2013. Retrieved September 8, 2014.
  40. ↑ Nicole Lee: Netflix and YouTube's DIAL promises to be open alternative to AirPlay . In: Engadget . AOL Inc. January 24, 2013. Retrieved August 31, 2013.
  41. ↑ How can Chromecast connect to your friend's phone without using WiFi? Ultrasonic Sounds , techcrunch.com
  42. ↑ Google: How does guest mode work?
  43. ↑ Requirements for Chromecast devices. In: Chromecast Help. support.google.com, accessed August 16, 2017 .
  44. ↑ Chromecast specifications. In: google.com. Retrieved August 16, 2017 .
  45. ↑ Set up Chromecast. In: Chromecast Help. support.google.com, accessed August 16, 2017 .
  46. ↑ Set up and manage guest mode. In: Chromecast Help. support.google.com, accessed August 16, 2017 .
  47. ↑ Stream the Android screen with the Google Home app. In: Chromecast Help. support.google.com, accessed August 16, 2017 .