Dreambox: Обзор моделей и технологий

Dreambox is a series of Linux powered DVB satellite, terrestrial and cable digital television receivers (set top boxes), produced by German multimedia vendor Dream Multimedia.

The Linux based production software originally used by Dreambox was originally developed for DBox2, by the Tuxbox project. The Dbox2 was a proprietary design distributed by KirchMedia for their pay TV services. The bankruptcy of KirchMedia flooded the market with unsold boxes available for Linux enthusiasts. The Dreambox shares the basic design of the DBox2, including the Ethernet port and the PowerPC processor. Its firmware is officially user upgradable, since it is a Linux based computer, as opposed to third party "patching" of alternate receivers. All units support Dream's own DreamCrypt conditional access (CA) system, with software emulated CA Modules (CAMs) available for many alternate CA systems. The built in Ethernet interface allows networked computers to access the recordings on the internal hard disks on some Dreambox models. It also enables the receiver to store digital copies of DVB MPEG transport streams on distributed file systems or broadcast the streams as IPTV to VideoLAN and XBMC Media Center clients. Unlike many PC based PVR systems that use free to air type of DVB receiver cards, the built in conditional access allows receiving and storing encrypted content. In 2007, Dream Multimedia also introduced a non Linux based Dreambox receiver, the DM100, their sole to date, still featuring an Ethernet port. It has a USB B port for service instead of the RS 232 or mini USB connectors found on other models. Unlike all other Dreamboxes, it features an STMicroelectronics CPU instead of PowerPC or MIPS.

There are a number of different models of Dreambox available. The numbers are suffixed with S for Satellite, T for Terrestrial and C for Cable:

DM 56x0 7000 7020 7025(+) 500(+) 100 600 PVR 800HD 820HD 8000 500HD 800HD se 7020HD 500HD v2 800HD se v2 7020HD v2 7080HD Production Life cycle 2003 2003 2005 2006 2006 2007 2007 2008 2012 2015 2009 2012 2010 2013 2010 2013 2011 2013 2013 2013 2013 2014 SoC STB04500 STB04500 STB04500 Xilleon 226 STB025xx ST5100 STB025xx BCM7401 BCM7400 BCM7405 BCM7405 BCM7405 BCM7405 BCM7405 BCM7405 BCM7435 CPU type PPC PPC PPC MIPS PPC RISC PPC MIPS MIPS MIPS MIPS MIPS MIPS MIPS MIPS MIPS MIPS CPU (MHz) 252 252 252 300 252 243 252 300 400 400 400 400 400 400 400 1400 RAM (MiB) 64 64 64 128 32 (96) 64 96 256 2048 256 256 256 512 512 512 512 2048 Flash (MiB) 8 8 32 32 8 (32) 32 32 64 4096 128 64 64 1024 1024 1024 1024 4096 Flash type NOR NOR NAND NAND NOR (NAND) NOR NAND NAND NAND NAND NAND NAND NAND NAND NAND eMMC Default OS Enigma1 Enigma1 Enigma1Enigma2 (beta) Enigma2 Enigma1 ST OS Enigma1Enigma2 (beta) Enigma2 Enigma2 Enigma2 Enigma2 Enigma2 Enigma2 Enigma2 Enigma2 Dreambox OS DVB 1 × S 1 × S 1 × S 2 × S/C/T 1 × S/C/T 1 × S 1 × S/C/T S+S2/C/T 1 × S/C/T (modular) 2 × S+S2 (2 × S/C/T optional) 1 × S2 1 × S/C/T 1 × S2, 1 x C+T (in total 2x DVB S/C/T optional) 1 × S2 1 × S/C/T 1 × S2, 1 x C+T (in total 2x DVB S/C/T optional) 2 x S2 (2 * S/C/T optional) HDTV Yes Common Interface CompactFlash Smart card Host USB Service LAN (Mbit/s) 100 (DM5620) HDD ATA RF mod. SCART HDMI / HDCP DVI Display LNB pass thru S/PDIF Optical +RCA Modem Other connectorsS VideoS Video HDMI InComponent, S Video

**HDMI via DVI to HDMI adapter. Remark: The new 7020hd v2 has a new Flash with another structure, that is why you need a different Linux Image. All new v2 Modells have a new TPM module inside. The rest of the Hardware is identical with the older one.

The DM 7000 is based around the IBM STB04500 controller, featuring a PowerPC processor subsystem and hardware MPEG decoding, has 64 MiB of RAM, 8 MiB of NOR flash memory (directly executable), a Common Interface slot, a dual smart card reader, a CompactFlash card reader, a USB 1.1 port, and an IDE (also known as PATA) interface for attaching an internal 3.5 in hard disk drive to convert the unit into a digital video recorder. Accepts only 230 V AC power. Because the boot loader resides in flash memory, this model may require the use of a JTAG in case of bad flashing which destroyed the boot loader. However, a bad flash will occur under rare scenarios, and rarely, almost never, will you need a JTAG.

There was a DM 5600 and also a DM 5620 model. The only difference being that the DM 5620 included an Ethernet port. Otherwise, the DM 56X0 models were a cut down version of the DM 7000 without an IDE interface. They did, however, include an RF modulator allowing them to be used with older TVs that lack a SCART connector.

The DM500 is the successor to the DM5620 and is the smallest and cheapest Dreambox. It is based around an IBM STBx25xx Digital Set Top Box Integrated Controller, featuring notably a 252 MHz PowerPC processor subsystem, hardware MPEG 2 video and audio decoding and smart card interfaces. The DM500 features 32 MB of RAM and 8 MB of NOR flash memory, of which 5 MB are used for read only firmware (cramfs and squashfs filesystems), 256 kB by the boot loader and the rest by a writable jffs2 filesystem. It has the standard features of a free to air (FTA) satellite receiver, plus extensive Fast Ethernet networking connectivity and a single smart card reader. It does not feature a 7 segment LED display, normally found in other FTA decoders. Also has the ability to be used on Digital satellite, cable and terrestrial broadcasts (also known as DVB S, DVB C, DVB T). The DM500+ model has 96 MB of RAM instead of 32, and 32 MB of NAND flash instead of 8 MB of NOR flash. This makes it similar to the DM600 PVR model. It is only available in DVB S versions. The new DM500HD was announced in Cologne on May 26, 2009. The price will be between € 350 and € 400.

The DM 7020 is essentially an updated DM 7000 with 96 MiB of RAM, 32 MiB of NAND flash (disk like) and an RF modulator. Changes were also made on the software side, utilizing Open Embedded for the base Linux operating system. Because the flash memory of this model is not directly executable, the primary boot loader resides in ROM and can recover corrupted secondary boot loader in flash by loading from the serial port. There are some Enigma 2 (beta) images already available for this model.

The DM 7025 is similar to the DM7020 but with the ability to add a second "snap in" tuner that makes it possible to watch one program while recording another. It is possible to change the tuner module, selecting between any two of Satellite, Terrestrial or Cable versions. Internally, it features a Xilleon 226 system on a chip from ATI, integrating a 300 MHz MIPS CPU core instead of the traditional PowerPC found in other models, and has 128 MiB of RAM. It uses Enigma 2, this is a complete rewrite of the original Enigma GUI, and is still going through growing pains as features that were present in Enigma are added to Enigma2. Enigma2 is Python based instead of C code. The DM 7025 has the ability to decode MPEG 2 HD as well. Unfortunately, it must downconvert this to 480i or 576i to display it. The DM 7025+ model features an Organic light emitting diode (OLED) display instead of an LCD one, an eject button on the Common Interface slot and improved power supply.

The DM 600 PVR is the same small size as the DM 500 but includes an IDE interface allowing to add an internal 2.5 in laptop type hard disk drive, the box will only recognise 5600rpm drives. On the outside it adds an S Video output connector and an analog modem port. It is built around the same IBM STBx25xx integrated controller, but features 32 MiB of flash and 96 MiB of RAM, of which 64 MiB are user accessible. It is possible to change the tuner module, selecting between Satellite, Terrestrial and Cable versions. There is still just one SCART connector and no 7 segment LED display, just 2 status LEDs. The provided remote control unit is the same one supplied with the 7000, 7020 and 7025 and allows one to control the TV set as well.

This is essentially a high definition version of the DM 600 PVR, featuring a single pluggable DVB tuner (S/S2, C or T), a 300 MHz MIPS processor, 64 MiB of Flash memory, 256 MiB of RAM and room for an internal SATA 2.5 in disk. It also features one DVI to HDMi Cable, two USB 2.0, one eSATA and one 10/100 Mbit/s Ethernet interfaces. It has an OLED display. DM 800HD se was introduced in late 2010. The main differences of the DM800HD se compared to the DM 800HD are a 400 MHz MIPS processor, a HDMI connector and a color OLED display. Another difference is the improved system chip in DM800se providing native DIVX support among other improvements.

This is the high definition PVR. Like the DM 7025, it supports pluggable tuner modules. In addition to High Definition, it has an upgrade for a DVD drive (slot in). And it has USB 2.0. Physically on the box it has one DVI port, but with the supplied DVI to HDMi Cable you get HDMI video. Originally announced to become available in the beginning of 2007, its release date was pushed back. The product then began shipping on 12.12.2008. The planned features were revised as well. Originally, this model was supposed to have 128 MiB of RAM (now 256), 32 MiB of flash (now 256 MiB) and a 300 MHz processor (now 400 MHz Broadcom 7400). Other Linux based HD receivers became available in the meantime. In June 2012, Dream Multimedia announced the discontinuation of the DM 8000 HD PVR because several electronic components are no longer available. It was also announced, that no direct successor will be developed since Dream Multimedia is already working at "Project Goliath".

"Project Goliath", announced in June 2012, is supposed to be a possible successor of several Dreambox models. According to Dream Multimedia, it is a "totally new hardware and software product, combining all the features of the successful Dreambox series, and indeed will go beyond that".

The factory installed distribution on the Dreambox is mostly available under the GNU General Public License (GPL) and uses standard Linux API's, including Linux DVB API and Linux Infrared Remote Control (LIRC). Several models (7025, 800 and 8000) use GStreamer as a multimedia framework. This configuration encourages enthusiasts to modify its functions, particularly in the form of so called images.

There are also many third party addons and plugins available that will extend the functionality of the Dreambox. Some plugins are model specific, while others run on all boxes. Plugins such as Jukebox and SHOUTcast playback, also external XMLTV guides, a web browser are available, and a VLC media player interface for on demand streaming media. Games are also abundant like Pac Man and Tetris. In addition, unofficial third party conditional access software modules (CAMs or emulators) are widely circulated on the Internet that emulate the CA systems developed by NDS (VideoGuard), Irdeto, Conax, Nagravision, Viaccess and other proprietary vendors. Some Dreambox owners use these softcams in conjunction with card sharing software to access pay TV services without a subscription card inserted in every connected box. This practice may be illegal in some jurisdictions and third party software for this purpose is neither officially endorsed nor supported by Dream Multimedia and voids the official warranty.

Clones of the DM500 S are wide spread. As a result, Dream Multimedia introduced the DM500+, with changes to try to prevent further counterfeiting. Clones also exist of DM500, DM800, DM800se and DM800se V2 built around the same commodity IBM SoC chip and hence having identical or slightly superior features they are also sold without the Dreambox brand name (e. g., the Envision 500S, with 48 megabytes of RAM instead of 32, also available in a 500C cable version, the Eagle box or the Linbox 5558, or Sunray DM800se). They have a retail price approaching that of non Linux receivers, generally a fraction of the Dreambox 500 price. Since they contain a copy of the copyrighted original DM500 bootloader program, the legality of these devices is questionable. In April 2008, Dream Multimedia allegedly introduced a time bomb into their latest flash to disable the boot loader on counterfeit models. An unofficial firmware group called Gemini who used the latest flash drivers in their firmware, found that flash corruption would be caused on clone DM500 S receivers. Other developers of unofficial firmware groups would find boxes to be affected by this if they use the latest drivers, providing another time bomb is to be introduced.