Glossary Of Terms

Copied from Black Hole's thread on hummy.tv

BYTs

Bright Young Things - Fittingly at the top of the list (even though I've thought of something to explain starting with "A"), BYTs is the term I've coined for the fantastic bunch with the youth and energy to figure out the hacks that we are celebrating on this forum. Wind the clock back 20 or 30 years and it could have been me, but the brain now struggles to keep up. Don't worry, the rest of this glossary is serious!

AR

Accurate Recording - See EPG.

CRID, PRID, SRID

Content Reference IDentifier - The EPG provides unique reference codes to the programmes which are useful for machines to track the programmes (and potentially to retrieve additional information via the Internet). The Programme CRID (PRID - unofficial) identifies the programme individually and allows the Humax to ensure that repeats don't get recorded, the Series CRID (SRID - unofficial) allows it to identify programmes to be recorded by series link. The CRID codes can be seen on the Humax programme information screen (via the "i" button) by turning them on in the secret menu.

DHCP

Dynamic Host Configuration Protocol - For your devices to co-exist on your home network, they each need a unique "address" so that data meant for a particular device gets there and not somewhere else. This is the IP (Internet Protocol) Address, and typically for a home network the addresses will be 192.168.0.x or 192.168.1.x (where x is 0-255). It is possible to allocate these addresses manually, but it is a chore and you have to make sure you choose a valid address and don't allocate the same address to more than one device. DHCP is an automatic system which lets the device request an address from a manager device - often the router in your broadband connection.

DLNA

Digital Living Network Alliance - a set of standards which allow compatible devices to locate each other on the local Ethernet network, and access each other's content for streamed playback, without the user having to understand network configuration settings. If you want to use the Humax' media streaming capability to show it's content elsewhere (firmware update 1.02.20 onwards), you will need a DLNA client - possibly a program running on a PC, or another Humax box - although it is possible to use non-DLNA media players if you can work out the correct network reference. The advantage of using another Humax is that it can access the HiDef content too (most other solutions will only access StDef recordings - see DTCP). You can also use a DLNA server to provide content to the Humax, again either running on a PC or using a NAS box with built-in DLNA capability (many do these days). See also uPnP.

DTCP

Digital Transmission Content Protection - a means of securing rights-restricted material transferred by any digital channel (in our case Ethernet). As a media server, the Humax protects HiDef recordings by DTCP, thus restricting your choice of clients to those which have paid the relevant licence fees (not unlike HDCP). Note that (by running the modified software) DTCP can be effectively switched off. See also HDCP.

EPG

Electronic Programme Guide - Along with the broadcast stations on Freeview comes a data channel containing information about the upcoming programmes (on all channels) for the next 8 days. This information is collected and organised for display when you press the "Guide" button. The content is broadcast continuously cyclically, with the more important information (the current channel, today) repeated more often than less important (other channels, programmes later in the future) so that the whole download is complete in about 15-20 minutes. In addition to the programme guide is a status channel for the Now/Next display and programme change-over, so that (in theory) PVRs can start a recording automatically at the start of a programme, even if it has been delayed (or brought forward). This is known as AR (Accurate Recording), but doesn't always work because broadcasters are not always reliable in transmitting this information (some worse than others). See also CRID.

Ext3

This is a method for arranging data on a hard drive, used by Linux systems (including the Humax). Unlike FAT32, it can accommodate huge video files without being truncated. Unlike NTFS, the Humax can write to it. Unfortunately, Windows PCs can't access it without help in the form of a special driver. The Humax can format a drive up to 1TByte to Ext3 through its menus (which will wipe anything that's on the drive), but beware that the Humax format has compatibility issues with other Linux systems (and also possibly the Windows driver). If you are adding an external drive to the Humax that will be dedicated to the purpose - no problem, but if you might want to connect the drive to other systems and access the contents it would be as well to format it elsewhere. See also FAT32 and NTFS.

FAQ

Frequently Asked Questions - the popular Internet abbreviation for the section of a web site that contains information which the authors are fed up with answering individually, or expect to be asked so they put it up as a pre-emptive measure. FAQ has since been adopted to mean any unchanging reference material.

FAT / FAT32

File Allocation Table - This is a method for arranging data on a hard drive, the other main one from the PC point of view being NTFS. The original FAT was only suitable for small drives, but in those days drives were only small. FAT32 drives can be much bigger (2TByte), but something to be very aware of when playing with video is the file size limit: each individual file on a FAT32 drive can be no greater than 4GBytes in size (that's a couple of hours of StDef, but less than an hour of HiDef). A Windows PC can access a FAT32 drive no problem, so can Linux and the Humax - but if the Humax tries to write a file that is larger than 4GBytes to a FAT32 drive, the file will be truncated and the Humax won't tell you there has been an error. See also NTFS and Ext3.

Foxy

Recordings made by the Humax are encrypted on the drive using a code unique to each individual box. Directly accessing the recording files (eg by FTP) sees only the encrypted files, so any files extracted are only any use for backup purposes and must be replaced on that specific Humax to be decrypted for replay. Copying an StDef recording to USB using the Humax menus obligingly decrypts the file, but not so HiDef recordings - which remain encrypted to oblige the broadcasters. Foxy is a utility that runs on a Windows PC and is capable of clearing the Enc flag on a HiDef recording, and thus make it decryptable just like a StDef recording. See also .ts. Users of the modified software can clear the Enc flag automatically within the Humax, no need for Foxy.

FTP

File Transfer Protocol - a simple (for computers) standard for two devices to communicate across a network for copying files about. Both ends have to understand FTP (and have it turned on) for it to work though! With FTP turned on in the menu settings, it is possible to access the Humax by FTP. Typically one runs an FTP client on the PC which then provides drag-and-drop file management.

HD / HiDef

High Definition - I use HiDef to disambiguate from other meanings of HD: eg Hard Drive, or HD-FOX T2. By HiDef we mean the content recorded from the Freeview HD channels eg BBC HD, BBC1 HD etc.

HD / HDD

Hard (Disc) Drive (for completeness) - computer disc drive, either bare for inclusion in a piece of equipment or housed in a case for connection by USB (external/portable hard drive).

HDCP

High bandwidth Digital Content Protection - How do the big film companies publish HiDef Blu-ray video discs and stop them being instantly pirated? Well, there's not much chance of stopping determined pirates, but they can stop the ordinary public from making a copy to pass around the family (or a legitimate safety backup) by making sure the content never appears accessibly in the clear (code-speak for unencrypted). HDCP is enforced by licence - equipment makers have to sign up to it to be granted access to the technology, pay a lot for it, and they undertake not to let the datastream out. What it does is to negotiate the HDMI link. If the source is providing copy-protected material, it first negotiates with the destination that it requires a secure link (and only an HDCP-compliant device knows how to negotiate), the link is established, and then the video is sent until the link gets broken (and has to be re-negotiated). What is true of Blu-ray is also true of FreeviewHD - the broadcasters wish to keep control of it - so the Humax also negotiates a secure link with the TV. See also HDMI.

HD-FOX T2

The version of the Humax FreeviewHD tuner/PVR which does not include an internal hard drive and therefore only records to an external drive. "HD" for FreeviewHD, "T2" is the modulation scheme for broadcast digital HD used in the UK (not in common with most of the rest of the world). The HD-FOX T2 is also one tuner short of a full set (deficient in the tuner division to the leg of one).

HDMI

High Definition Multimedia Interface - Unless you have a steam telly and are using the SCART interface, HDMI will be the type of connection you are using to send the video/sound to your TV (I still have a couple of tellies that don't even have SCART). In essence: SCART is an analogue interface, in other words the picture information is sent as continuous voltage levels; whereas HDMI is a digital interface and every single pixel on the screen is defined precisely by (typically) three bytes of data, 25 times a second. Add it up - that's a lot of data! SCART is okay for traditional 625-line pre-digital TV, but the analogue waveforms cannot keep up with the detail in HiDef video. The digital data in HDMI means that at each binary bit of every pixel, the transmission scheme only has to successfully communicate the difference between a "1" and a "0" - and even that is tricky at up to 340 million bits per second over a few metres of cheap cable. See also SCART, HDCP.

HDR-FOX T2

The version of the Humax FreeviewHD tuner/PVR which does include an internal hard drive. "HDR" for FreeviewHD Recorder, "T2" is the modulation scheme for broadcast digital HD used in the UK (not in common with most of the rest of the world).

Humax / Hummy

Abbreviated / jocular reference to a box made by Humax (the company). In this section of the Hummy.tv forum it would be natural to assume the author is referring to the HDR-FOX T2 unless otherwise stated. Much of the discussion here also applies to the HD-FOX T2, as indeed most of the discussion in the HD-FOX T2 section also applies here (I assume).

.hdf

Humax Download Format (unsubstantiated) - Software updates for the Humax are distributed as .hdf files. If a USB memory stick is plugged into the Humax at boot-up, and it contains a .hdf file (precisely named "hdr_fox_t2_upgrade.hdf") in the top directory, the Humax will start a firmware/software update from the file (even if that version of software is already installed). The modified software is also distributed as .hdf files. Updating by downloading a .hdf to a USB stick is an alternative to the OTA (Over The Air) update service that happens automatically in areas able to receive FreeviewHD.

NAS

Network-Attached Storage - an external hard disc drive accessed by an Ethernet connection instead of a USB cable. This means its content can be accessed by anything on the network, not just the PC it happens to be plugged into, and doesn't rely on the PC being turned on. Of course, if you have a USB drive plugged into the Humax and the Humax is on, you have a DLNA NAS (in addition to the drive already in the Humax).

NTFS

New Technology File System - NT as in Windows NT, the basis of modern Windows (as opposed to the Win3.1 - Win98 - WinME product line). This is a method for arranging data on a hard drive, the other main one from the PC point of view being FAT32. NTFS does not suffer the file size limits of FAT32. A Windows PC can access a NTFS drive no problem, Linux can now but used to have trouble, but the Humax can only read from an NTFS drive - it can't write to it (although the modified software project may add that capability one day). See also FAT32 and Ext3.

PRID

Programme Reference IDentifier - Unofficial, see CRID.

PVR

Personal Video Recorder - Traditionally, a broadcast video recorder that records programmes to an internal memory/hard drive rather than a removeable disc (eg DVD-R) or tape cassette, therefore the recording is only available personally.

Samba

Windows PCs can share their drives over a network so that the PCs can access the files on a remote PC as if they were on the local PC. The Linux method for sharing drives (compatible with Windows shares) is Samba. With the modified software installed on the Humax, Samba can also be installed and that makes the files on the Humax directly accessible from Windows PCs across the network, just like a local file. This means that any media player compatible with the .ts file format (once decrypted) can play the file regardless of DLNA, and fast-forward/rewind will work.

SCART

Radio and Television Receiver Manufacturers' Association (in French) - Basically the chunky 21-pin connector that was used to connect AV equipment before HDMI came along. The Humax simultaneously outputs video and audio digitally on the HDMI, and to conventional analogue TV standards on the SCART and the phono connectors (composite video plus stereo audio - query: is RGB available on the SCART?). If you have an analogue DVD recorder, the SCART is probably the quickest way to copy a programme from the Humax to disc - the alternatives being a time-consuming process of decrypting and copying the content to a PC, then converting the file format to suit a DVD and burning it. See also HDMI.

SD / StDef

Standard Definition (see also HiDef) - By StDef we mean the content recorded from the Freeview non-HD channels.

SRID

Series Reference IDentifier - Unofficial, see CRID.

.ts

Transport Stream - this is the "file type" of a video file recorded on the Humax, and each recording comprises a set of four files (three in the case of a radio recording) - all with the same name but having different file types, the important one being the .ts. Pressing the "Media" button on the handset lists the file sets, but to see the individual files requires exploring the Humax drive by FTP. Note that the .ts files as recorded by the Humax are encrypted, and if copied by FTP they remain encrypted. Decrypting the files requires a copy to be performed by the Humax menus onto an external drive (or a virtual drive if using the modified software, network drives in the future), and in the case of HiDef .ts files only after first clearing the Enc flag in the recording's file set (see Foxy). Files are also decrypted on-the-fly when being streamed to a DLNA client.

uPnP

Universal Plug-n-Play - A set of standards which provide the self-configuration we enjoy with our computer equipment these days. Remember when it used to be necessary to install and configure some kind of driver before anything would work at all? No?? You don't know you're born! These days, plug in a USB memory stick or a printer, chances are the operating system will think a little while and then the device is ready for use. USB uPnP standards are responsible for this, the hardware in the device is able to identify itself on request, then the operating system configures built-in drivers to deal with it. DLNA provides uPnP across a network, so for example a media streaming client is able to locate a server on the network without human intervention. See DLNA.

USB

Universal Serial Bus - the (currently) ubiquitous socket for connecting peripherals to PCs, or in our case for connecting an external storage device (memory stick or portable hard drive) to the Humax. The HDR-FOX T2 has two USB sockets: one on the front under a flap, and one on the rear immediately below the Ethernet socket.