Video Notes
for Sunday, 7/19/2015

Google Earth Pilots Eye Flight Path Tour
Direct Link to video on Vimeo: https://vimeo.com/135482867

The video is a Google Earth "Tour" extracted to an "Image Stream" (many files / giga disc space) via Google Earth Pro (Pro is free as of 2015).  The Google Earth "Image Stream" was imported into Adobe Premiere Pro (NLE video software) as an "Image Sequence" to produce the video output.  You can also simply play a tour in Google Earth, but Google Earth may or may not have it's own set of issues depending your processor speed and internet connection.  By producing a version of the tour as a video, the individual Google Earth user setting aren't an issue, so there is more control of the communication intent.  Google Earth is a better overall tool for flight evaluation, but the video brings a sample to those who either don't have Google Earth loaded on their immediate computer or aren't very adept at navigating in Google Earth.

The video is posted to Vimeo as a full 1920x1080 HD file at 30 frames per second.  A higher frame rate would be more appropriate for panning, but the bit rate would be excessive for web delivery at 60 FPS.  30 FPS at 1920x1080 may be marginal for slower internet connections, even after significant compression by Vimeo.

The Google Earth Player does offer "SD" playback, but if stuttering is an issue a better option is to simply download the video file rather than streaming it.  See [Web Streaming Playback vs Download Notes].

Google Earth Pro has numerous options for extracting video.  You can go straight to a video format, which is likely faster, requiring less disc space, but streaming direct to a video codec could result in dropped frames depending on the internet connection speed.  Exporting as an "Image Stream" requires a lot of disc space, and takes a long time, but it is a more deliberate process that will produce one jpg image for each frame.  The 13 minute image sequence at 60 FPS took about 12 hours to capture 27 Giga Bytes needed for almost 50 thousand jpg images.  I watched a short YouTube video to learn the basics of exporting a Google Earth "Image Stream" at https://www.youtube.com/watch?v=IknS8zQ7zLQ

Google Earth Pro (you need the Pro version to export "movie" stuff) has a number of configuration options.  You can export at a lower frame rate to reduce required resources, but during my testing, the panning shots were blurry.  By reducing 60 FPS to 30 FPS (in the editor), we effectivly reduce the playback speed by half (or increase the time by 2).  There were parts that needed to slow down (panning and yawing), but we were also able  to speed up some of the glides to keep the playback time as short a possible.  Another of the Google Earth options is Tour "Speed".  The unitless range goes up to 1000 with 200 as the default.  Using a faster speed will record fewer frames compared to slower speeds which take more time to complete the same "Tour".

There are multiple ways to make a tour, but of particular interest to us is to make a "Tour from a Path" (GPS flight track).  How "tight" the Tour follows the flight path is related to the "Tour Speed".  Faster speeds result in a looser tour that glosses over the details and follows the path only generally, which is good for our applications because no one really wants to get dizzy watching the view go around in circles.  I opted for a compromise of using a speed of 500 because I wanted to have some panning in a few places, but the setting resulted in more unwanted panning "yaw" compared to the faster speeds like 700 and 1000.  In hindsight, I could have spliced multiple tours together with transitions in-between clips to achieve a smoother flow with less yaw, but still achieve panning in a few places were desired.  Using transitions would be more appropriate if the primary objective was instruction, but one of my objectives for this video was documentation because it was a historic flight, so I wanted to have a continuous tour without clip transitions, however, if I do it again for other flights I'll opt to splice in transition because the yawing and jerky motion of the tighter flight path is problematic.  I don't think you splice clips together seamlessly without transitions because the actual camera tracks aren't the same at different speeds, but with transitions, we can use the high frame rate stuff for the parts that need to slow down and track tight for clarification, and the higher speed low frame rate option which has less yawing for the general path.

Another configurable options is how close the "camera" trails the path point.  Greater distances result is smoother flow where tight distances will track tighter.  I used 100 meters for this production.  The "camera" flies 100 meters behind the pilot, so it won't try to follow the pilot around a 75 meter circle.

This was my first Adobe Premiere Pro project.  I've done a few prior projects with simpler software, but opted to switch to Premiere for a number of reasons.  I was previously using Cyberlink Power Director, which was faster to learn the basics, but the learning resources were limited.  Premiere has a ton of learning resources (on-line tutorials and discussion groups).  Back when I bought Power Director for about a hundred dollars, Premier cost close to a thousand.  I didn't want to spend the money and the learning curve is steep.  Now that the Creative Suite is subscription based rather than outright purchase, money is not the issue anymore because the various programs are bundled into Adobe's Creative Suite rather than a la carte, so I bit the bullet and struggled through the essential training.

My first Premiere Pro project was somewhat of a learning experiment, so I tried different things.  Some worked  better than others, but it's all very time intensive.  I could have gone back and fixed some of the stuff I did early, but I'll leave it for what it's worth and continue to make adjustments on future projects.  I could have narrated the Tour, but I think narration is more appropriate for a spliced clip project with varied media assets.  The pace is also too fast for worthwhile narration that could lend insight into the scenarios.  The labels serve as a form of limited narration,  providing orientation and clarification.  I considered doing the music thing, but because my primary objective for this production was documentation and education rather than entertainment, the cost to benefit ratio of mixing in music wasn't there for me.

To more effectivly assess the day, a viewer should also look at the still photos to get a sense of the sky, view the 3D flight path in Google Earth, and read the flight articles and weather perception.

Something I would like to include in future projects is a compass (I think I could have simply left the Google Earth navigation tool on?).  Some sort of altitude indication might also help a viewer with orientation.

The Hurricane Dolores Remnants linked to in the Weather Archive was my 2nd Adobe Premiere Pro video project.
Direct Link to video on Vimeo: https://vimeo.com/135789354

The primary source material was a YouTube video Posted by NOAA from a Geostationary Satellite GOES-15.  The direct NOAA link was
http://www.nasa.gov/feature/goddard/nasa-sees-tropical-storm-dolores-affecting-southwestern-mexico
which ran an imbedded YouTube link
https://www.youtube.com/watch?v=yt6xI2p4kcU

The main challenge in this project was the low resolution and frame rate of the original video downloaded from YouTube via http://keepvid.com  The original posting to YouTube by NOAA was only 486x380 at 6 FPS.  I tried searching for better source material to work with, but NOAA's YouTube posting seemed to be the best option available.  The NOAA GOES Project archives have varied still images in the archives, but they are all low resolution with no better time sampling.  The YouTube video was a "special weather event" production, (Dolores was the strongest hurricane to date this season) so it had more visually appealing enhancements than the stock archive offerings.

To lengthen the duration (run time) the original YouTube posting had repeating frames inserted every 3rd frame, so it had a double bounce (stutter), one for the low frame rate, and one for the asymmetrically added frames.  To complicate matters, Premiere would accept the 6 FPS rate but if you edited any of the sequence parameters, Premiere would then change the sequence to it's minimum selectable frame rate which appears to be 10 FPS, which is not divisible by 6, so...?

To address the frame rate stutter, I was able to re-interpolate the clip/sequence frame rate (a Premier tool under the Modify Menu) from 6 FPS to 12 FPS, which didn't insert or remove frames, but changes how fast the frames are played back, so it cut the duration (run time) in half.  I was then able to manually remove the repeating frames (manually because I couldn't figure out how to do it automatically).  Trying to adjust the frame rate in the "Sequence" rather than the source clip was problematic because doing so would simply add frames, which aggravated the issue and might have been why the original YouTube version has a double stutter.

To get extra frames to work with, I exported the 12 FPS Sequence to render at 60 FPS with "Blend Mode" selected in the export options to create 4 new frames (60/12-1) for a total of 5 blended frames per original satellite photo.  The blending made the video a bit blurry, but it also made it smoother and slower, thus longer.  This video was already blurry and choppy, so the blending degradation was outweighed by the smoothness and additional frames to work with.

Since we planned to interpolate new frames with the blend mode, we did the size bump first so the interpolator would have more pixels to work with.  The original size was only 486x360, so I multiplied it by 3 to get 1080.  I could have used 2x to get 720, but our interest in viewing the local weather requires some zoom and I don't think anyone is watching at 360 anyway.  We did another 2x zoom for the trailing clips to help view the local cloud cover at flight time.  The 2nd zoom is 6x magnification (3x2)over the original size, so we are stretching the limits.

We doubled the frames again to 10 per satellite photo to achieve the slow motion effect for enhanced flight zone evaluation.  We tried slower speeds by interpolating more frames, but the quality suffered too much so we backed off.  The 2nd frame doubling was a cascade on top of the initial 5 frame per satellite photo interpolation because the highest export rate that Premiere supports is 60 FPS (60/12=5), so to get to 10 we doubled the initial 5 frame interpolation.

All the markups were done as linked Illustrator files because Adobe's title tool is lacking some basic functions like being able to zoom in the builder window to see where you are placing stuff.