Understanding and Converting GPS Coordinates

If you’ve used a global position system (GPS) device or an online map application, you may have noticed that geographic locations on earth can be precisely described using latitude and longitude values. Latitudes range from -90 to +90 degrees, where -90 degrees is the South Pole, 0 degrees is the equator, and +90 degrees is the North Pole. Longitudes range from -180 to +180 degrees, where 0 degrees longitude is the Prime Meridian on which the Royal Observatory sits in Greenwich, England.

You may have also noticed that there are 2 main systems for the communication of latitude and longitude: degrees/minutes/seconds (DMS, a.k.a. “sexagesimal degrees”) and decimal degrees (DD). In DMS notation, each degree is divided into 60 minutes, and each minute is divided into 60 seconds, just like a clock. Fractions of sections can be represented by decimals. In DD notation, the latitude and longitude coordinates are simply expressed as decimals, with a greater number of decimal places conferring greater geographic precision.

To complicate matters, in both DMS and DD notations, locations relative to the equator and Prime Meridian can be expressed using either positive/negative values or north (N), east (E), south (S), and west (W) designations. Positive latitudes are N of the equator, while negative latitudes are S of the equator. Positive longitudes are E of the Prime Meridian, while negative longitudes are W of the Prime Meridian.

There may be times when you may need to interconvert between DMS and DD notations. For example, if you need to navigate to a certain location and are provided with DMS coordinates, it may be easier (or possibly your only option) to enter DD coordinates into your GPS device. A free DMS-DD converter is provided by the Federal Communications Commission, and there are numerous other free options available.

Video Conversion with HandBrake

I recently wrote about My Digital Content Workflow, and in step 7 I describe how I had been using Xilisoft Video Converter to resize videos from 1080p ("full HD") to smaller sizes like 720p ("HD"). Given that a new version of HandBrake (0.10.0) was released just 2 days ago, I thought I'd give it another look. HandBrake is traditionally known for being used as a DVD ripping application, so I had never seriously considered it for video conversion, although it has had those capabilities for quite some time.  With release 0.10.0 comes several new encoding schemes which I'll probably never use, but it's nice to know that the developers are staying current with newer codecs like H.265 (even if it is still in early development at this stage).

For a vast majority of my needs, I will generally start with a preset and make further adjustments from there.  For example, the iPad present defaults to a 720p resolution, and I might just modify the bitrate to achieve a level of quality that is suitable for the contents of the video that I am converting. I find that a bitrate of 5000 kbps results in pretty good quality, especially for viewing on mobile devices and YouTube, although it is possible to get away with 3000 kbps or less if the video does not contain a lot of fast-moving images.

Overall I'm pleased with HandBrake as a video conversion tool, and given that it is free, it is hard to beat HandBrake in terms of value.  Furthermore, HandBrake is available for both Mac and Windows (and Ubuntu, if you're into that).  If you have any other recommendations for video conversion, I'd like to know!