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TIFF and LibTiff Mail List Archive

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2003.09.19 07:16 "[Tiff] Stripsize when writing as scanlines (and huge image flipping).", by =?iso-8859-15?B?VuRpbvYgSuRydmVs5A==?=
2003.09.18 10:42 "[Tiff] Stripsize when writing as scanlines (and huge image flipping).", by =?iso-8859-15?B?VuRpbvYgSuRydmVs5A==?=
2003.09.18 13:09 "[Tiff] Stripsize when writing as scanlines (and huge image flipping).", by Frank Warmerdam
2003.09.18 13:28 "[Tiff] Stripsize when writing as scanlines (and huge image flipping).", by =?iso-8859-15?B?VuRpbvYgSuRydmVs5A==?=
2003.09.18 13:38 "[Tiff] Stripsize when writing as scanlines (and huge image flipping).", by Frank Warmerdam

2003.09.18 13:09 "[Tiff] Stripsize when writing as scanlines (and huge image flipping).", by Frank Warmerdam

V�in� J�rvel� wrote:

How does libtiff write images with no TIFFTAG_ROWSPERSTRIP set and written using TIFFWriteScanline? I wanted to have random access to these files for flipping rows (first row to last etc.) so i tried using 1 row/strip but it was _really_ slow and the file sizes were big.

Do you have any ideas how i could implement this?

(The images are too big to be read in the memory at once so i am reading them scanline at a time as it seemed appropriate because i'm also doing some modifications on the scanlines.)

I thought about reading scanline at a time and writing out as strips (writing as stripes smaller than the picture should work with random-access, right?).

V�in�,

Using ROWSPERSTRIP of 1 for this purpose seems quite reasonable. I don't see why it would be slow or produce files any larger than normal. Perhaps you could make an example of the file produced available?

Note that some compression types do not work well with 1 row per strip. I was assuming uncompressed.

Best regards,

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