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== A note on "HDTV ready" computer-hardware ==
== A note on "HDTV ready" computer-hardware ==
Nowadays, many DVB-cards (whether USB or PCI, whether DVB-T or DVB-C) are advertised with "HD-ready" or "HDTV" (for example, the newest [[TwinhanDTV Digital Terrestrial TV Card Ter|Twinhan DVB-T card]]. But then, what does this really mean? An MPEG2 [[TS]] in principle can always have high-definition contents, the TS container doesn't bother. It might mean, the card won't freak out if a TS/PS is not MPEG2, but MPEG4 (as this encoder is often used for HDTV). If might also mean, the card can handle high bandwidth TS (e.g. about 15 Mbit/s for HD-BBC in the DVB-T testrun in London, as opposed to 4 Mbit/s for the regular SDTV). But this is all not well defined, and therefore, this "HDTV ready" sticker might be more of a PR-thing...
Nowadays, many DVB-cards (whether USB or PCI, whether DVB-T or DVB-C) are advertised with "HD-ready" or "HDTV" (for example, the newest [[TwinhanDTV Digital Terrestrial TV Card Ter|Twinhan DVB-T card]]. But then, what does this really mean? An MPEG2 [[TS]] in principle can always have high-definition contents, the TS container doesn't bother. But the sticker might mean that the card won't freak out if a TS/PS is not MPEG2, but MPEG4 (as this encoder is often used for HDTV). It might also mean, the card can handle high bandwidth TS (e.g. about 15 Mbit/s for HD-BBC in the DVB-T testrun in London, as opposed to 4 Mbit/s for the regular SDTV). But this is all not well defined, and therefore, this "HDTV ready" sticker might be more of a PR-thing...


However, '''in no case''' does it mean, the hardware has a hardware-decoder for HDTV-resolutions ([[full-featured cards]]). Such PCI-cards don't exist yet (end of 2006). (This makes it difficult to use them with the software [[VDR]], as that one mostly relies on hardware-decoding.)
However, '''in no case''' does it mean, the hardware has a hardware-decoder for HDTV-resolutions ([[full-featured]] cards). Such PCI-cards don't exist yet (end of 2006). (This makes it difficult to use them with the software [[VDR]], as that one mostly relies on hardware-decoding.) The decoding therefore has to be done by the CPU, and HDTV requires fast hardware (>2GHz processors).


This note is complicated by the fact that many broadcaster will not send HDTV free to air, but either encrypt it (making additional hardware necessary: [[CI]], [[CAM]], which is not always possible for a given DVB-card) or turn a No-Copy-Flag on, which (at least currently) means it can't be handled by Linux.
This note is complicated by the fact that many broadcaster will not send HDTV free to air, but either encrypt it (making additional hardware necessary: [[CI]], [[CAM]], which is not always possible to find for / connect to a given DVB-card) or turn a No-Copy-Flag on, which (at least currently) means it can't be handled by Linux. See also [[DVB-S2]].





Revision as of 00:35, 26 December 2006

High-Definition Television. Means Broadcasts with higher resolutions than PAL or NTSC. For standards and backgrounds, see the Wikipedia article [1].


Getting some HDTV with Linux

A note on "HDTV ready" computer-hardware

Nowadays, many DVB-cards (whether USB or PCI, whether DVB-T or DVB-C) are advertised with "HD-ready" or "HDTV" (for example, the newest Twinhan DVB-T card. But then, what does this really mean? An MPEG2 TS in principle can always have high-definition contents, the TS container doesn't bother. But the sticker might mean that the card won't freak out if a TS/PS is not MPEG2, but MPEG4 (as this encoder is often used for HDTV). It might also mean, the card can handle high bandwidth TS (e.g. about 15 Mbit/s for HD-BBC in the DVB-T testrun in London, as opposed to 4 Mbit/s for the regular SDTV). But this is all not well defined, and therefore, this "HDTV ready" sticker might be more of a PR-thing...

However, in no case does it mean, the hardware has a hardware-decoder for HDTV-resolutions (full-featured cards). Such PCI-cards don't exist yet (end of 2006). (This makes it difficult to use them with the software VDR, as that one mostly relies on hardware-decoding.) The decoding therefore has to be done by the CPU, and HDTV requires fast hardware (>2GHz processors).

This note is complicated by the fact that many broadcaster will not send HDTV free to air, but either encrypt it (making additional hardware necessary: CI, CAM, which is not always possible to find for / connect to a given DVB-card) or turn a No-Copy-Flag on, which (at least currently) means it can't be handled by Linux. See also DVB-S2.