Author Topic: GPS Variables  (Read 4916 times)

Offline IanGoldstein

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GPS Variables
« on: July 18, 2007, 07:59:37 PM »
I realize these are minor items, but for the various GPS related variables would the following be possible...

(1) The ability to show {latitude} and {longitude} variables in the form of Degrees-Minutes-Seconds rather than the current Degrees-Minutes form? It is shown as Degrees-Minutes-Seconds with the "Show Map" command, but the variables only display Degrees-Minutes. Perhaps an option under Preferences to allow us to select coordinate formatting. Personally, I think coordinates should be displayed in a consistent manner within the program, so whatever formatting option a user selects should be used for both the variables and the show map command.

(2) With regards to consistent formatting of coordinates, on the Show Map window the coordinates are shown without N/S and E/W references. It would be better if these references were included as they are with the {latitude} and {longitude} variables, rather than with the current +/- signs. (As of July 19th, I see that this item has been implement - Thanks!)

(3) While I realize GPS data records altitude as meters, it would be nice to be able to display altitude in terms of feet. Perhaps an {altitudeft} variable could be added?

(4) On the Show Map window, it might be useful to set the title for the caption rather than just showing the filename. The ability to set the text as we can set the text for thumbnail labels (on the Contact Sheet tab of Preferences) would work nicely. We wouldn't need more than one text field for multiple lines. A single text field which ideally allows us to include {nl} variables to create multi-lined text and defaults to "{file}" would work well.

(5) If the altitude information is available, could it be displayed along with the latitude and longitude on the Show Map window? Alternatively, if we could have multiple lines for a title in item #4 above, we could just as easily include the {altitude} variable.

-Ian
« Last Edit: July 20, 2007, 06:36:58 AM by IanGoldstein »

Offline dennis

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Re: GPS Variables
« Reply #1 on: July 21, 2007, 11:50:11 AM »
(1) The ability to show {latitude} and {longitude} variables in the form of Degrees-Minutes-Seconds rather than the current Degrees-Minutes form? It is shown as Degrees-Minutes-Seconds with the "Show Map" command, but the variables only display Degrees-Minutes. Perhaps an option under Preferences to allow us to select coordinate formatting. Personally, I think coordinates should be displayed in a consistent manner within the program, so whatever formatting option a user selects should be used for both the variables and the show map command.

Currently PM formats these coordinates depending on how the data is stored in the Exif GPS block.  The GPS data is stored as 3 rational (numerator/denominator) values for degrees, minutes, and seconds.  Normally one would expect the degrees and minutes to be whole numbers (i.e. denominator is 1), and the seconds to have a fractional part (denominator > 1).  But apparently many GPS units (or maybe it is just Nikon's firmware) report the minutes with a denominator > 1 and seconds = 0.  For example, I get 100 for the minutes denominator and 0 seconds with my D200/Garmin eTrex.  In this case PM uses a mm.mmm format for its coordinate variables.  If the values were stored as minutes being a whole number then PM would show it as ddd?mm'ss.s".  I'm not sure how I had my GPS formatted but maybe it was set to mm.mmm, and maybe if I switch it to mm'ss.s" it will come through with the Exif GPS data formatted accordingly.

The coordinates from the Show Map command are actually converted on our server to ddd?mm'ss.s" from Google's required ddd.ddddd? format.

I suppose we could add a preference to control the coordinate formatting, either ddd.ddddd?, ddd?mm.mmm', or ddd?mm'ss.s".

(3) While I realize GPS data records altitude as meters, it would be nice to be able to display altitude in terms of feet. Perhaps an {altitudeft} variable could be added?

How about another preference along with coordinate formatting?

(4) On the Show Map window, it might be useful to set the title for the caption rather than just showing the filename. The ability to set the text as we can set the text for thumbnail labels (on the Contact Sheet tab of Preferences) would work nicely. We wouldn't need more than one text field for multiple lines. A single text field which ideally allows us to include {nl} variables to create multi-lined text and defaults to "{file}" would work well.

I saw this one coming...  Yet another preference I suppose.  We could make this one or two lines.

Offline IanGoldstein

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Re: GPS Variables
« Reply #2 on: July 23, 2007, 01:55:59 PM »
Currently PM formats these coordinates depending on how the data is stored in the Exif GPS block.  The GPS data is stored as 3 rational (numerator/denominator) values for degrees, minutes, and seconds.  Normally one would expect the degrees and minutes to be whole numbers (i.e. denominator is 1), and the seconds to have a fractional part (denominator > 1).  But apparently many GPS units (or maybe it is just Nikon's firmware) report the minutes with a denominator > 1 and seconds = 0.  For example, I get 100 for the minutes denominator and 0 seconds with my D200/Garmin eTrex.  In this case PM uses a mm.mmm format for its coordinate variables.  If the values were stored as minutes being a whole number then PM would show it as ddd?mm'ss.s".  I'm not sure how I had my GPS formatted but maybe it was set to mm.mmm, and maybe if I switch it to mm'ss.s" it will come through with the Exif GPS data formatted accordingly.
That makes sense now. I took a look at the actual EXIF GPS data in one of my photos and can see that it too is recorded with fractional minutes and no seconds (N 41/1 deg, 425/100 min, 0/1 sec, W 47/1 deg 5142/100 min 0/1 sec). I see that it seems to be a suggested option in the EXIF ver 2.2 specs.

Quote from: dennis
The coordinates from the Show Map command are actually converted on our server to ddd?mm'ss.s" from Google's required ddd.ddddd? format.
I assumed that was the case.

Quote from: dennis
I suppose we could add a preference to control the coordinate formatting, either ddd.ddddd?, ddd?mm.mmm', or ddd?mm'ss.s".
I think that would be nice and imagine it should be fairly easy to implement.

Quote from: dennis
Quote from: IanGoldstein
(3) While I realize GPS data records altitude as meters, it would be nice to be able to display altitude in terms of feet. Perhaps an {altitudeft} variable could be added?
How about another preference along with coordinate formatting?
A preference option would work if the {altitude} variable included units. If a person was to include an altitude variable within a caption, they would more than likely add an "m" or "ft" suffix as appropriate. However, if they later changed the altitude unit preference, the values would be correctly displayed but their hard-coded suffix in their captions would be incorrect. My suggestion would be to either have 2 separate variables, or include an "m" or "ft" unit suffix as part of the value returned by {altitude}. Just my 2-cents.

Quote from: dennis
Quote from: IanGoldstein
(4) On the Show Map window, it might be useful to set the title for the caption rather than just showing the filename. The ability to set the text as we can set the text for thumbnail labels (on the Contact Sheet tab of Preferences) would work nicely. We wouldn't need more than one text field for multiple lines. A single text field which ideally allows us to include {nl} variables to create multi-lined text and defaults to "{file}" would work well.
I saw this one coming...  Yet another preference I suppose.  We could make this one or two lines.
To keep it as simple as possible, perhaps you could just setup 2 preference fields -- GPS Caption Title and GPS Caption Text.  The text (after variable substitution) would be passed to your server for display with Google Maps. The Caption Title could default to "{file}" and the Caption Text to "{latitude}, {longitude}".  A separate title vs. text value allows you to continue to show a simple title in bold text as is currently done with the Show Map command, without further complicating Photo Mechanic. Again, it would be ideal if the caption text could support multiple lines of text, but I imagine that would be more of a function of the Google Maps API and what it supports than a function of Photo Mechanic.

-Ian