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HD recorder project

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Manve_13

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Hey all,

I want to build my own hd recorder. It will be take digital hd input from a source, then it will store it to a internal hdd or usb flash disk. And there will be a output so I can play stored hd videos by this hdmi output.

Now I'm planning to use Via EPIA m800 board with 1gb ram. Do you think this board and it's cpu can handle this project? Or can you suggeset another board that has HD input and outpu(DVI or HDMI), LVDS interface to support LCD in fron of the panel and handle to store and play HD videos.

And I want to build a panel in fron the of the box. How I can setup the connection the buttons and board. There is a Digital I/O pin header. But I don't know how it works exactly. As I searched I can use USB HID but I'm not sure about that one too.

Thanks.
 
Quite an ambitious project.

You pretty much need a hardware accelerator to compress the video. Saving uncompressed HD video to hard drive is impractical.

HDMI is another problem. For HDCP protected content the data stream is encrypted by a proprietary chip handshake in the display.

There are boxes out there for less then $200 that take HD component video and output H.264 compressed data stream.
 
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If you're recording ATSC it is stored uncompressed. Check out the SageTV site to see how to build a DVR.
Why do you say it's uncompressed? The ATSC signal is significantly compressed with MPEG-2. I would expect this signal to be stored in the compressed form to save space, and then uncompressed when it is viewed.

If you mean that the ATSC signal is not compressed further for storage, then I'm sure that's true, since that would likely degrade the signal as MPEG-2 is already lossy compression.
 
Why do you say it's uncompressed? The ATSC signal is significantly compressed with MPEG-2. I would expect this signal to be stored in the compressed form to save space, and then uncompressed when it is viewed.

If you mean that the ATSC signal is not compressed further for storage, then I'm sure that's true, since that would likely degrade the signal as MPEG-2 is already lossy compression.

It's a .ts file.

File extension TS offers features for error correction for transportation over unreliable media, and is used in broadcast applications such as DVB and ATSC.
 
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It's a .ts file.

File extension TS offers features for error correction for transportation over unreliable media, and is used in broadcast applications such as DVB and ATSC.
So what is "It's". Is that used to store HD video on a PC? Is it an uncompressed file?

I know from the size of the recorded file (about 4GB/Hr) that DirecTV, which uses MPEG-4 compression, likely stores the compressed MPEG-4 data directly, since it's significantly smaller than uncompressed video on a Blu-Ray disc.
 
.TS is mpeg2 compression. MPEG4 is a group of specs of which H.264 is subpart (MPEG4 part 10). It is probably the best compression/quality at present in a fast evolving technology.

H.264 is what Apple and Flash uses. It is processing intensive to encode, so hardware acceleration for full HD TV is almost a must.

H.264 compressed files are 1.5-3X smaller then MPEG2 for equivalent quality. Many cable boxes have adopted it since they want to jam the most channels in available RF channels.

.TS, Apple, and Flash are transport streams which beyond the actual video compression used, contains how audio is included, other information packets like source info (TV channel info, subtitle text, etc.) and encryption if used.
 
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H.264 compressed files are 1.5-3X smaller then MPEG2 for equivalent quality. Many cable boxes have adopted it since they want to jam the most channels in available RF channels.
Yes. A couple years ago DirecTV junked all its HD satellite boxes that could only decode MPEG2 for new boxes that could decode both MPEG2 and MPEG4, since they were moving all channels to MPEG4. That must have given them a large write-off for the year.
 
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HD is compressed but at the source not by your PC or video card. Your PC will save it in the same formet as the broadcast.

Not so, and not so. You can transcode any format to any format. Just processing power. You need a hardware accelerator card to do it in real time.

Directv transcodes ATSC mpeg2 .ts stream to H.264 in real time.
 
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So what is "It's". Is that used to store HD video on a PC? Is it an uncompressed file?

I know from the size of the recorded file (about 4GB/Hr) that DirecTV, which uses MPEG-4 compression, likely stores the compressed MPEG-4 data directly, since it's significantly smaller than uncompressed video on a Blu-Ray disc.

Directv HD DVR records the signal essentially as the raw demodulated RF stream (separating out a particular sub-channel). It includes their encryption so you can not play it back if the unit is no longer under authorized subscription.
 
Directv HD DVR records the signal essentially as the raw demodulated RF stream (separating out a particular sub-channel). It includes their encryption so you can not play it back if the unit is no longer under authorized subscription.
That recorded encryption must be something new, since I recently fired up my old DirecTV HD MPEG2 Tivo receiver, which is no longer under subscription, and was able to view all the recorded shows without it being connected to an antenna.
 
That recorded encryption must be something new, since I recently fired up my old DirecTV HD MPEG2 Tivo receiver, which is no longer under subscription, and was able to view all the recorded shows without it being connected to an antenna.

It obviousl depends if the original was encrypted or not, and to what degree - PVR's work by directly recording the direct digital datastream, encrypted or not makes no difference. Any required decryption required is done as you play it back.
 
Not so, and not so. You can transcode any format to any format. Just processing power. You need a hardware accelerator card to do it in real time.

Directv transcodes ATSC mpeg2 .ts stream to H.264 in real time.

Yes you can transcode but you don't have to. WMC, Beyond TV & SageTV do not convert an HD broadcast by default. The wee EPIA would take days to transcode a 2hr movie.
 
It obviousl depends if the original was encrypted or not, and to what degree - PVR's work by directly recording the direct digital datastream, encrypted or not makes no difference. Any required decryption required is done as you play it back.
Apparently the DirecTV encryption is detected by the receiver to allow communication with the satellite only if you are a subscriber. But this encryption is not recorded and/or not checked when playing back recorded video. Makes sense, since they don't really care about the video after it's been legitimately recorded from an encrypted signal.
 
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