<html><head></head><body><div>
<meta charset="utf-8">
<div id="compose-body-wrapper" dir="auto"><div dir="auto"><div dir="auto">Hello Even,</div><div dir="auto">Thank you for the quick reply. I'll try using GDAL subdatasets later this afternoon (although I'm not sure if this solution would become a bit messy for hundreds of files). The format KEA is completely new to me. I was able to install KEALib but found only one source of information online (https://gdal.org/drivers/raster/kea.html). To start somewhere, I simply modified the first 2 lines of the script to:</div><div dir="auto"> driver_name = 'KEA'</div><div dir="auto"> driver = gdal.GetDriverByName(driver_name)</div><div dir="auto">However, it doesn't pick it up (driver returns 'None'). Ideally there would be some example that I could follow but I might have to do this piecewise in the meantime. </div><div><br></div></div></div><div class="replyHeader" dir="auto">Even Rouault wrote:</div><br><br><div><blockquote cite="mid:c95e84f0-04c3-4533-6be5-34e07c4744e6@spatialys.com" type="cite" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<p>Hi,</p>
<p>The TIFF format only supports only single color table per TIFF
image, and it only makes sense for a single-sample TIFF. An
alternative would be for you to create multiple TIFF image file
directories in the same file (mapped as GDAL subdatasets), with
one band per subdataset, by using the APPEND_SUBDATASET=YES
creation option.</p>
<p>Another option is to use the KEA format (specialization of HDF5)
which supports all the possibilities of the GDAL abstract data
model.</p>
<p>Even<br>
</p>
<div class="moz-cite-prefix">Le 14/02/2023 à 17:25, afernandez a
écrit :<br>
</div>
<blockquote type="cite" cite="mid:cf35d819b16e3.4ed0e9f08beef@odyhpc.com">
<div>
<div id="compose-body-wrapper" dir="auto">
<div dir="auto">
<div dir="auto">Hello,</div>
<div dir="auto">I'm using the GDAL Tools plugin within QGIS
to plot some raster layers. The snippet reads:</div>
<div dir="auto"><i> driver_name = 'GTIFF'</i></div>
<div dir="auto"><i> driver =
gdal.GetDriverByName(driver_name) </i></div>
<div dir="auto"><i> ...</i></div>
<div dir="auto"><i> gdal_ds =
driver.Create("my_arguments") </i></div>
<div dir="auto"><i>
gdal_ds.SetProjection("my_projection")</i></div>
<div dir="auto"><i>
gdal_ds.SetGeoTransform("my_geo_transform")</i></div>
<div dir="auto"><i> for band_idx in range(1, times +
1):</i></div>
<div dir="auto"><i> band =
gdal_ds.GetRasterBand(band_idx) </i></div>
<div dir="auto"><i> band.SetNoDataValue(no_data)</i></div>
<div dir="auto"><i>
band.SetDescription(time_step)</i></div>
<div dir="auto"><i> data = var[band_idx - 1]</i></div>
<div dir="auto"><i> data = ma.getdata(data)</i></div>
<div dir="auto"><i>
band.WriteArray(data.astype(np_dtype, copy=False))</i></div>
<div dir="auto"><i> gdal_ds.FlushCache()</i></div>
<div dir="auto">This works without any problem and plots the
raster in greys. However, I need the plot to be colored so
I modified the code based on some posts, which now
reads: </div>
<div dir="auto"><i> gdal_ds = driver.Create(out_path,
cols, rows, times, gdal.GDT_UInt16) </i></div>
<div dir="auto"><i>
gdal_ds.SetProjection("my_projection")</i></div>
<div dir="auto"><i>
gdal_ds.SetGeoTransform("my_geo_transform")</i></div>
<div dir="auto"><i> for band_idx in range(1, times +
1):</i></div>
<div dir="auto"><i> band =
gdal_ds.GetRasterBand(band_idx) </i></div>
<div dir="auto"><i> band.SetNoDataValue(no_data)</i></div>
<div dir="auto"><i>
band.SetDescription(time_step)</i></div>
<div dir="auto"><i> data = var[band_idx - 1]</i></div>
<div dir="auto"><i> data = ma.getdata(data)</i></div>
<div dir="auto"><i> data_scaled =
np.interp(data, (data.min(), data.max()), (0, 255))</i></div>
<div dir="auto"><i> data_scaled2 =
data_scaled.astype(int)</i></div>
<div dir="auto"><i> colors = gdal.ColorTable()</i></div>
<div dir="auto"><i> colors.CreateColorRamp(0,
(229, 245, 249), 127, (153, 216, 201))</i></div>
<div dir="auto"><i> colors.CreateColorRamp(127,
(153, 216, 201), 254, (44, 162, 95))</i></div>
<div dir="auto"><i>
band.SetRasterColorTable(colors)</i></div>
<div dir="auto"><i>
band.SetRasterColorInterpretation(gdal.GCI_PaletteIndex)</i></div>
<div dir="auto"><i> band.WriteArray(data_scaled2)</i></div>
<div dir="auto"><i> gdal_ds.FlushCache()</i></div>
<div dir="auto">The problem is that this produces a
RunTimeError: SetColorTable() not supported for
multi-sample TIFF. I simplified this for a single band and
QGIS did plot the colored raster. However, this is not a
solution because production runs will generate dozens (or
even hundreds) of time step bands. I'm pretty new to GDAL
so I'm unsure if this is a feature under current
development or if there are other alternatives so any
suggestion on how to proceed would be appreciated.</div>
<div dir="auto">Thank you in advance.</div>
</div>
<div dir="auto"><br>
</div>
</div>
</div>
<br>
<fieldset class="moz-mime-attachment-header"></fieldset>
<pre class="moz-quote-pre" wrap="">_______________________________________________
gdal-dev mailing list
<a class="moz-txt-link-abbreviated" href="mailto:gdal-dev@lists.osgeo.org">gdal-dev@lists.osgeo.org</a>
<a class="moz-txt-link-freetext" href="https://lists.osgeo.org/mailman/listinfo/gdal-dev">https://lists.osgeo.org/mailman/listinfo/gdal-dev</a>
</pre>
</blockquote>
<pre class="moz-signature" cols="72">--
<a class="moz-txt-link-freetext" href="http://www.spatialys.com">http://www.spatialys.com</a>
My software is free, but my time generally not.</pre>
</blockquote></div>
</div></body></html>