## org.autoplot.pngwalk.RichPngUtil

At the 2012 MMS meeting at UNH, a group of us proposed that we embed a little metadata within PNG images which provides lookup information in JSON format. Here is an example:

>      { "size":[722,639],
>      "numberOfPlots":1,
>      "plots": [
>         {
>           "title":"AC/MFI  [PRELIMINARY VALUES - BROWSE USE ONLY] B-field magnitude",
>           "xaxis": { "label":"", "min":"2014-01-02T00:00:00.000Z", "max":"2014-01-03T00:00:00.000Z", "left":78, "right":644, "type":"lin", "units":"UTC" },
>           "yaxis": { "label":"[PRELIM] <|B|> (nT)", "min":4.440892098500626E-16, "max":8.9, "top":52, "bottom":587, "type":"lin", "units":"nT" }
>         }
>      ] }

See http://autoplot.org/richPng

## RichPngUtil( )

## getRange

getRange( JSONObject axis ) → DatumRange

return the range setting of the axis. This looks at the "min" and "max" keys of the axis node.

### Parameters

axis - a JSONObject

### Returns:

the axis range
[search for examples] [view on GitHub] [view on old javadoc]

## getXRange

getXRange( String json ) → DatumRange

attempt to get the time range of the plots, looking at each x axis for a timerange.

### Parameters

json - rich png ascii string

### Returns:

null or the range found.
[search for examples] [view on GitHub] [view on old javadoc]