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Date: Sun, 30 Dec 2001 20:34:39 -0800
From: Peter Montgomery <pjmonty@csi.com>
Subject: Re: Partial Extraction of a Scanline?
To: tiff@olympiakos.com
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Bad,

    I don't believe that you can read a partial scanline, however,
others on the list may correct this.  If the image were tiled, you could
of course read it a tile at a time and build your own scanline.
However, I am curious just how big can your scanline possibly be?  An
image that is 32,0000 pixels across (mighty big in my opinion) and RGBA
would still take up only 128 KB of memory.  Certainly this wouldn't take
long to allocate at all.  Even if the image were 1 million pixels across
and RGBA, it would still take only 4 MB of memory.  Just how big are
these images that allocating a buffer big enough to hold it would take
any appreciable amount of time?

    Thanks,
    PeterM

----- Original Message -----
From: "Bad Badtz" <badtzbad@hotmail.com>
To: <tiff@olympiakos.com>
Sent: Sunday, December 30, 2001 8:15 PM
Subject: Partial Extraction of a Scanline?


>
> Hi!
>
> I understand that LibTIFF provides APIs to read the scanlines, strips
or
> tiles of a TIFF or GeoTIFF image. However when reading just one
scanline of
> a striped image that is rather huge (a few GBs), a big buffer needs to
be
> created and it will take a long time.
>
> Is there anyway I can read parts of a scanline instead of the whole
> scanline?


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