[Qgis-user] QGIS Master and Rasters to grayscale

[Marco Hugentobler]

Ticket filled:

http://hub.qgis.org/issues/5837

Am 21.06.2012 13:02, schrieb James Stott:
> There is a sample of this data at:
>
> http://www.ordnancesurvey.co.uk/docs/sample-data/10k-raster-colour-sampl
> e-data.zip
>
> If you turn this grayscale in 1.9 it just turns grey (rgb 127,127,127)
> all over. In 1.8 if you choose grayscale it displays it with the rgb
> values displayed below.
>
> So I created a colormap if anyone is interested. I took the values from
> what QGIS 1.8 did automatically to turn the data grayscale.
>
> Value - r ,g ,b
> 0 = 255,255,255
> 1 = 0,0,0
> 2 = 226,226,226
> 3 = 150,150,150
> 4 = 218,218,218
> 5 = 232,232,232
> 6 = 232,232,232
> 7 = 230,230,230
> 8 = 249,249,249
> 9 = 252,252,252
>
> I have created a qml file if anyone would like it you can download it
> from here:
>
> https://docs.google.com/open?id=0B6r5nAOdEBZrRFpjVlBLZm1BSkE
>
> This was quite easy as there were only 10 values defined in the data.
>
> The OS 25000 and 50000 rasters have 255 different colours in them.
>
> James
>
>
>
>    |
> Nicholas Pearson Associates |
> T:  | M:
> http://www.npaconsult.co.uk/
> -----Original Message-----
> From: qgis-user-bounces at lists.osgeo.org
> [mailto:qgis-user-bounces at lists.osgeo.org] On Behalf Of James Stott
> Sent: 19 June 2012 14:40
> To: Etienne Tourigny
> Cc: qgis-user at lists.osgeo.org
> Subject: Re: [Qgis-user] QGIS Master and Rasters to grayscale
>
> Yes.
>
> It still turns into one colour.
>
>
> James Stott BSc (Hons) MSc | Senior Professional Nicholas Pearson
> Associates | 30 Brock Street | Bath | BA1 2LN
> T: 01225 445548 | M: -
> http://www.npaconsult.co.uk/
> -----Original Message-----
> From: Etienne Tourigny [mailto:etourigny.dev at gmail.com]
> Sent: 19 June 2012 14:33
> To: James Stott
> Cc: Salvatore Larosa; qgis-user at lists.osgeo.org
> Subject: Re: [Qgis-user] QGIS Master and Rasters to grayscale
>
> DId you click on "Load" Button?
>
> On Tue, Jun 19, 2012 at 10:22 AM, James Stott
> <James.Stott at npaconsult.co.uk>  wrote:
>>> You can still do that by selecting "singleband gray", and choose the
> default contrast enhancement in the options.
>> This just turns the raster into 1 gray colour: 127, 127, 127
>>
>>> can you share a bit sample of your raster?
>> Technically I don't think I supposed to share the data as it is
> Ordnance Survey data.
>> I have included the metadata below if this helps:
>>
>> Driver:
>> GDAL provider
>> VRT
>> Virtual Raster
>> Dataset Description
>> N:\Projects\10499 BP\Reference\Base Mapping\Raster\10000\OS 10000.vrt
>> Band 1
>> STATISTICS_MAXIMUM=9
>> STATISTICS_MEAN=3.2746921074487
>> STATISTICS_MINIMUM=0
>> STATISTICS_STDDEV=3.9133672791329
>> Dimensions:
>> X: 39370 Y: 31496 Bands: 1
>> Origin:
>> 385000,95000
>> Pixel Size:
>> 0.635001,-0.635001
>> No Data Value
>> -32768
>> Data Type:
>> GDT_Byte - Eight bit unsigned integer
>> Pyramid overviews:
>> Layer Spatial Reference System:
>> +proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000
>> ++y_0=-100000 +ellps=airy +towgs84=375,-111,431,0,0,0,0 +units=m
>> ++no_defs
>> Layer Extent (layer original source projection):
>> 385000.0000000000000000,75000.0000000000000000 :
>> 410000.0000000000000000,95000.0000000000000000
>> Band
>> Band 1
>> Band No
>> 1
>> No Stats
>> No stats collected yet
>>
>>
>> James Stott BSc (Hons) MSc | Senior Professional Nicholas Pearson
>> Associates | 30 Brock Street | Bath | BA1 2LN
>> T: 01225 445548 | M: -
>> http://www.npaconsult.co.uk/
>>
>> http://www.npaconsult.co.uk/http://www.npaconsult.co.uk/about-news.asp
>>
>> From: qgis-user-bounces at lists.osgeo.org
>> [mailto:qgis-user-bounces at lists.osgeo.org] On Behalf Of Salvatore
>> Larosa
>> Sent: 19 June 2012 13:02
>> To: qgis-user at lists.osgeo.org
>> Subject: Re: [Qgis-user] QGIS Master and Rasters to grayscale
>>
>> Il giorno mar, 19/06/2012 alle 12.42 +0100, James Stott ha scritto:
>>> This does make what was a very simple thing to do in 1.8 more time
>>> consuming in 1.9 doesn't it? All I want to do is just turn it
>>> grayscale for display purposes. In 1.8, all I do is select grayscale
>>> from the colormap drop down and push OK and QGIS does it for me. Am I
>>> missing something?
>> Hi James,
>> can you share a bit sample of your raster?
>>
>> Regards,
>>
>> -SL
>>
>>
>> --
>> Salvatore Larosa
>> linkedIn: http://linkedin.com/in/larosasalvatore
>> twitter: @lrssvt
>> skype: s.larosa
>> IRC: lrssvt on freenode
>>
>> _______________________________________________
>> Qgis-user mailing list
>> Qgis-user at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/qgis-user
>>
>> http://www.npaconsult.co.uk/terms.asp
>> This Electronic Transmission is intended only for the attention of the
> addressee. It may contain privileged and confidential information. If
> you are not the person for whom it is intended, you must not copy,
> distribute or take any action in reliance on it. If you have received
> this electronic transmission in error please notify us immediately by
> telephone, delete the transmission and destroy any hard copies.
>> Nicholas Pearson Associates has used all reasonable efforts to ensure
> that this message and any attachments are free from viruses.
>> Nicholas Pearson Associates, 30 Brock Street, Bath, BA1 2LN , Tel: +44
>> (0) 01225 445548, Fax: +44 (0) 01225 312387, Website:
>> http://www.npaconsult.co.uk/
>> _______________________________________________
>> Qgis-user mailing list
>> Qgis-user at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/qgis-user
> _______________________________________________
> Qgis-user mailing list
> Qgis-user at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/qgis-user
> _______________________________________________
> Qgis-user mailing list
> Qgis-user at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/qgis-user


-- 
Dr. Marco Hugentobler
Sourcepole -  Linux&  Open Source Solutions
Weberstrasse 5, CH-8004 Zürich, Switzerland
marco.hugentobler at sourcepole.ch http://www.sourcepole.ch
Technical Advisor QGIS Project Steering Committee