HDR images from video with HDRinstant
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HDRlog have just announced the release of their standalone software HDRinstant. The software allows drone hobbyists and aerial videographers/photographers to create HDR images from video. The software also allows drone users to get great still grabs so they will never miss a great shot again.Whether you’re filming for real estate or just having fun, HDRinstant lets you transform your aerial videos into stunning images.
So, what’s this HDR thing then? Well, one of the ways aerial photographers can get a better shot is by using HDR or high dynamic range photography. This technique allows the photographer to manage scenes that contain a lot of contrast in order to produce a better representation of what the human eye can see.
Typically, three images are required to create a HDR image. Some cameras have an AEB function allowing this to be done automatically. Each image is exposed differently (for the lighter and darker parts of an image) and then combined to create a HDR image containing a lot of detail and color. This is only doable with a camera that has an AEB function but this is almost impossible to do whilst flying a drone. Not only do you need a drone that is capable of lifting a DSLR camera (very expensive due to weight constraints) but you need to keep the craft very still whilst shooting because any movement will result in blurred results (as you are taking multiple shots). It is also a good idea to have optimal weather conditions as winds can really affect your flight not to mention that you require a decent gimbal to stabilize your camera (it is a good idea to have one as it really make a difference to your captures). Did I mention GPS locking? It’d be good idea to have that too. You also have to switch modes during flight (between video and photo mode – but this is not a huge inconvenience admittedly).
HDRinstant now allows you to create HDR images from video! The software allows you to film a scene with a drone and create an HDR image from it. We’ll explain the process to you so read a little further. If you are just interested in still grabs, no problem. HDRinstant allows you to get single
images from your footage. See below.
The pilot has exposed the video to the highlights, making it quite dark. We could just take this image and increase detail in the shadows for example, whilst playing with other sliders to tone-map (a process used in HDR imaging that maps one set of tonal values to another) the image in the HDR process. However, if we were to do this, we would greatly increase noise in the underexposed areas. You certainly wouldn’t want to show this to your clients, let alone put it on your website. Here is an enlarged part of the image to give you an idea of what you would get.
As you can see the image on the left has been processed with HDRinstant and compared to the image on the right, it contains much less noise. The image on the right is just a single image that has been tone-mapped. You can however reduce the noise by using the technique below. To get better detail in the darker parts of the image, HDRinstant uses several images extracted from the video. This means that when you create your HDR image, HDRinstant takes a portion of your selected video as images and then stacks them. This is to increase the signal to noise ratio (SNR) and allows us to get better detail in the darker zones. Here is an example of an HDRinstant image
Here is an image taken from a video filmed on a drone. Whilst watching the video, we chose our favorite part. This was when the drone was at its highest point giving a great view of the scene. With HDRinstant we then extracted 25 images from the video and stacked them in order to create the final image. The only thing left to do was tone-map the image (essential in HDR image creation) and hey presto, an HDR image from video was created.
HDRinstant automatically removes any motion blur in the video as it applies a special morphing algorithm to create the final image. This allows you to create an HDR image. It is important to remember that a minimum of 1080p (full HD) resolution is recommended in order to create an HDR image; a lower resolution will limit the output quality for users. GoPro cameras are ideal for this – later models with 4K filming capabilities make results even better but the lower frame rate requires steadier flight.
HDRinstant beta is a standalone program for Windows and Mac and is currently available free of charge. Version 1 will be available for $89(US) including at least one year of upgrades but if you preorder, you will be able to take advantage of our offer – HDRinstant for $49(US). For more information or to download the software, visit http://hdrinstant.com
Thanks to our friends at http://dronestudio.fr for the footage.