My Humax Forum » Freeview HD » HDR FOX T2

Where is my space going?

(6 posts)
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    Luke

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    Hi. I’ve had an HD-FOX-T2 with a 80GB external hard drive attached for a few months.

    The HDD is filling up faster than I was expecting and I now see where it is going but don’t understand why.

    I recorded the same Radio and SD programmes on the 9200T and the HD-FOX-T2. The HD-FOX-T2 recordings take up about a third of a GB extra for each hour. I’d expect the AD to take up a bit of extra space but not that much. On Radio programmes the increase in size is dramatic. It’s 4 fold on BBC Radio 4 (bit rate 192Kbps), almost 5 fold on 4extra (160Kbps) and almost 7 fold on World Service (96Kbps).

    Can any of you guess or know what that the extra space is being used for? Or is it a bug that I should email to Humax?

    Does this also apply to the HDR-FOX-T2?

    | Wed 28 Dec 2011 13:44:29 #1 |
  2. grahamlthompson

    grahamlthompson

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    Most likely down to the cluster size used by the Operating System. A FS using more sectors to a cluster is inefficient with small files as a small increase in file may require a whole extra cluster. That space can't be used by any other file until the whole file is deleted.

    Disk FS are a trade off between large sectors and a relatively small file allocation table and small sectors requiring a larger space to keep track of the clusters used by any file.

    | Wed 28 Dec 2011 14:01:22 #2 |
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    Martin Liddle

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    Luke - 51 minutes ago  » 
    On Radio programmes the increase in size is dramatic. It’s 4 fold on BBC Radio 4 (bit rate 192Kbps), almost 5 fold on 4extra (160Kbps) and almost 7 fold on World Service (96Kbps).

    I have seen the suggestion by someone who investigated (can't find the quote right now) that the way radio programs are saved on the HD models is very inefficient.

    | Wed 28 Dec 2011 14:39:04 #3 |
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    Luke

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    Thanks Graham and Martin.

    The 9200T files and the HD-FOX-T2 files were copied to a FAT32 disk so that the comparison was reasonable. The increase from 29MB to 194 KB for the smallest recording (World Service 31 minutes) is massive.

    So far it is looking as though the solution is to watch/listen to recordings and delete them fast.

    On the HDR-FOX-T2 does the decryption of the SD recordings reduce the file size at all?

    | Wed 28 Dec 2011 15:38:58 #4 |
  5. grahamlthompson

    grahamlthompson

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    Luke - 24 minutes ago  » 
    Thanks Graham and Martin.
    On the HDR-FOX-T2 does the decryption of the SD recordings reduce the file size at all?

    Doubtfull, I imagine it's a byte for byte replacement just a different value than the in the clear recording.

    | Wed 28 Dec 2011 16:03:40 #5 |
  6. myhumax

    myhumax

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    The older Humax PVRs use the .ts format, the newer PVRs use the .m2ts format for recordings including radio (audio only). This could explain the file sizes.

    A 30 mins SD recording of Eastenders on the 26th gave:
    1, on the 9200T - 679,448,064 bytes
    2, on the HDR-FOX T2 - 870,313,984 bytes
    3, on the HDR-FOX T2 - gave same size decrypted (copied to external HDD)

    | Wed 28 Dec 2011 20:03:39 #6 |

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