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<blockquote data-quote="Elf" data-source="post: 58680" data-attributes="member: 13103">Ray, Thanks -&nbsp;&nbsp; Looks like a reinstall for me, then!Monkey,A normal analogue signal can go straight to your TV via the antenna, but if that signal comes into your computer it has to be converted to digital to be usable or stored on your hard drive.&nbsp; Your TV card will perform that conversion to raw digital, but the amount of information in video data is immense and so is normally then compressed, usually into MPEG2 format.&nbsp; This compression takes quite a bit of processing power to perform in real-time, and would take a decent CPU and work it quite hard.&nbsp; Doing it that way is commonly called &quot;software encoding&quot; and that's why the CPU spec for use with such cards is higher.&nbsp; Of course, a lot of analogue TV cards boast a hardware MPEG2 encoder.&nbsp; These cards automatically convert the signal to MPEG2 before suppling it to your PC, so there's no need for the CPU to get involved.A DVB-T signal is a digital signal in MPEG2 format already.&nbsp; All a DVB-T TV card has to do is read the signal and supply it to your computer.&nbsp; There is no MPEG2 encoding required as the signal is MPEG2 already.&nbsp; Once you have your MPEG2 file/stream you watch it by rendering the MPEG2 data as moving pictures and sound on your monitor/TV.&nbsp; This requires the compressed MPEG2 data to be decoded first - a job just as intensive as encoding it in the first place.&nbsp; Thankfully most decent graphics cards have built-in hardware MPEG2 decoders and will take-over or assist the process, otherwise it also has to be done by your CPU.Whatever jobs the hardware on a DVB-T card does, MPEG2 encoding is not one of them!&nbsp; I think it's just a case of some manufacturers confusing things by claiming their DVB cards have hardware encoders - I suppose they're trying to say there will be no CPU usage, but really they should say there is no encoding done at all (?)</blockquote>

[QUOTE="Elf, post: 58680, member: 13103"] Ray, Thanks - Looks like a reinstall for me, then! Monkey, A normal analogue signal can go straight to your TV via the antenna, but if that signal comes into your computer it has to be converted to digital to be usable or stored on your hard drive. Your TV card will perform that conversion to raw digital, but the amount of information in video data is immense and so is normally then compressed, usually into MPEG2 format. This compression takes quite a bit of processing power to perform in real-time, and would take a decent CPU and work it quite hard. Doing it that way is commonly called "software encoding" and that's why the CPU spec for use with such cards is higher. Of course, a lot of analogue TV cards boast a hardware MPEG2 encoder. These cards automatically convert the signal to MPEG2 before suppling it to your PC, so there's no need for the CPU to get involved. A DVB-T signal is a digital signal in MPEG2 format already. All a DVB-T TV card has to do is read the signal and supply it to your computer. There is no MPEG2 encoding required as the signal is MPEG2 already. Once you have your MPEG2 file/stream you watch it by rendering the MPEG2 data as moving pictures and sound on your monitor/TV. This requires the compressed MPEG2 data to be decoded first - a job just as intensive as encoding it in the first place. Thankfully most decent graphics cards have built-in hardware MPEG2 decoders and will take-over or assist the process, otherwise it also has to be done by your CPU. Whatever jobs the hardware on a DVB-T card does, MPEG2 encoding is not one of them! I think it's just a case of some manufacturers confusing things by claiming their DVB cards have hardware encoders - I suppose they're trying to say there will be no CPU usage, but really they should say there is no encoding done at all (?) [/QUOTE]

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