TRACE image processing

[wafels]

The TRACE images should be available in Helioviewer.org. Work has started on this - this issue will track progress.

[wafels]

The TRACE data processing pipeline runs and creates images - see #30 . However, the image when imported to SunPy shows the following error:

In [2]: m = sunpy.map.Map("/Users/ireland/2008_11_12__17_27_54_000__TRACE_TRACE_TRACE_171.jp2")
WARNING: SunpyUserWarning: This file contains more than 2 dimensions. Data will be truncated to the first two dimensions. [sunpy.map.mapbase]

In [6]: m.data.shape
Out[6]: (1024, 3)
In [7]: m.dimensions
Out[7]: PixelPair(x=<Quantity 3. pix>, y=<Quantity 1024. pix>)

Since other JP2 files made with JP2Gen are read as anticipated by SunPy there must be something unusual about the TRACE processing pipeline.

[wafels]

Some more information:

In [2]: import glymur

In [3]: jp2 = glymur.Jp2k("/Users/ireland/2008_11_12__17_27_54_000__TRACE_TRACE_TRACE_171.jp2")

In [4]: fullres = jp2[:]

In [5]: fullres.shape
Out[5]: (1024, 1024, 3)

In [6]: jpl = glymur.Jp2k(
   ...:     "/Users/ireland/Data/jp2/SOHO/2022_02_18__13_36_26_362__SOHO_LASCO_C2_white-light.jp2"
   ...: )


In [8]: fullres_l = jpl[:]

In [9]: fullres_l.shape
Out[9]: (1024, 1024)

[wafels]

I think the issue lies here: https://github.com/Helioviewer-Project/jp2gen/blob/master/idl/trace/hvs_trace.pro#L60 . The details structure gets the palette key. The value is an array of [3, 256]. The code that writes the JP2 file contains an option to use the palette in the details structure: https://github.com/Helioviewer-Project/jp2gen/blob/master/idl/gen/hv_write_jp2_lwg.pro#L581 . I think what is happening is that IDL then uses the palette to write out a JP2 file with RGB channels. I'll post this as an issue.