Try without internal mask.

Duarte

_____________________________________________
De: Ammar [mailto:ammar8...@yahoo.com]
Enviada: quinta-feira, 23 de Janeiro de 2014 14:28
Para: Etienne Tourigny
Cc: gdal dev
Assunto: Re: [gdal-dev] Question about gdaladdo and raster mosaicking


Etienne,

I tried the following:

gdalbuildvrt -srcnodata 255 -vrtnodata 255 -addalpha -input_file_list 
tiff_list.txt mosaic02.vrt

gdal_translate -of GTiff -b 1 -b 2 -b 3 -mask 4 -a_srs EPSG:3011 -co TILED=yes 
-co compress=jpeg -co jpeg_quality=80 -co blockxsize=512 -co blockysize=512 -co 
photometric=ycbcr --config gdal_tiff_internal_mask yes mosaic02.vrt mosaic02.tif

gdaladdo mosaic02.tif -r average --config COMPRESS_OVERVIEW JPEG --config 
JPEG_QUALITY_OVERVIEW 60 --config INTERLEAVE_OVERVIEW PIXEL --config 
PHOTOMETRIC_OVERVIEW YCBCR 2 4 8 16 32 64 128 256 512

Did I implement the mask the right way? The results I got were similar to the 
JPEG compression with no mask, in other words I got white lines too!








  ________________________________
From: Etienne Tourigny <etourigny....@gmail.com<mailto:etourigny....@gmail.com>>
To: Ammar <ammar8...@yahoo.com<mailto:ammar8...@yahoo.com>>
Cc: Chaitanya kumar CH <chaitanya...@gmail.com<mailto:chaitanya...@gmail.com>>; 
gdal dev <gdal-dev@lists.osgeo.org<mailto:gdal-dev@lists.osgeo.org>>
Sent: Thursday, January 23, 2014 12:25 PM
Subject: Re: [gdal-dev] Question about gdaladdo and raster mosaicking



As was suggested, you could try using a mask instead.



On Thu, Jan 23, 2014 at 7:52 AM, Ammar 
<ammar8...@yahoo.com<mailto:ammar8...@yahoo.com>> wrote:

Chaitanya,

Thank you very much for your reply and suggestion. I have used LZW with 
predictor 2 compression and added external overviews compressed in LZW too and 
the image came perfect. The only downside is the size of each of the images has 
expanded from approx. 2 GB to 18-20 GB. So now I have to choose between quality 
and size!

Attached are two screen shots showing the difference.

Thanks again!

Regards,
Ammar





  ________________________________
From: Chaitanya kumar CH <chaitanya...@gmail.com<mailto:chaitanya...@gmail.com>>
To: ammar8...@yahoo.com<mailto:ammar8...@yahoo.com>
Cc: gdal dev <gdal-dev@lists.osgeo.org<mailto:gdal-dev@lists.osgeo.org>>
Sent: Tuesday, January 21, 2014 6:27 PM
Subject: Re: Question about gdaladdo and raster mosaicking



Ammar,
You are using lossy JPEG compression. I'm guessing that the white lines are are 
actually pixels with values near but not equal to 255. So, they are not treated 
as nodata pixels.
My suggestion is to use another format with lossless compression for the 21 
images or use a mask band if you prefer.
Let me know how it goes.
--
Best regards,
Chaitanya Kumar CH
On 21-Jan-2014 5:31 pm, <ammar8...@yahoo.com<mailto:ammar8...@yahoo.com>> wrote:

Hello Chaitanya,

I was looking online for solutions to my problem and I cam across some of your 
posts so I thought you might help me with my problem.

I have 10,000+ TIFF files that I want to merge into one big Image and serve 
using GeoServer. I merged every 500 images at a time creating using 
gdalbuildvrt and gdal_translate along with JPEG compression creating 21 TIFF 
files. I added overviews then to each of the new 21 files. When adding the 
images together, once directly as files using QGIS and another time as WMSs 
using GeoServer, I got white lines/gaps precisely at the border of ever 2 
images. I thought the problem is with no data values but I decided to take 
another approach and merged all the 10,000 files into one huge image and this 
time I got one perfect image with no lines or gaps. I failed to create 
overviews for the big image because the process took days or gdaladdo running 
with no progress. I tested then on smaller images with and without overviews 
and the ones with no overview came perfect while the one with gdaladdo 
overviews came with the same problem of lines and gaps. The commands I m using 
are the following:

 gdalbuildvrt -srcnodata 255 -vrtnodata 255 -a_srs EPSG:27700 -input_file_list 
tiff_list.txt mosaic.vrt

gdal_translate -of GTiff -co TILED=YES -co BIGTIFF=YES -co COMPRESS=JPEG -co 
JPEG_QUALITY=80 -co BLOCKXSIZE=512 -co BLOCKYSIZE=512 -co PHOTOMETRIC=YCBCR 
mosaic.vrt mosaic.tif

gdaladdo mosaic.tif -r average --config COMPRESS_OVERVIEW JPEG --config 
JPEG_QUALITY_OVERVIEW 60 --config INTERLEAVE_OVERVIEW PIXEL --config 
PHOTOMETRIC_OVERVIEW YCBCR 2 4 8 16 32 64 128 256 512

Any ideas, tips or recommendations would be appreciated!

Best regards,
Ammar

_____________________________________
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http://osgeo-org.1560.x6.nabble.com<http://osgeo-org.1560.x6.nabble.com/>






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