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Super Resolution

   I ran across a university site in Israel a decade or so ago. Technion was ahead of its time, at least the computer science department. Among subjects, explored there, was super resolution.      Take a low resolution image and apply processing to get a larger image with the same level of detail.,    My first instinct was that the task was impossible. You would hasve to manufacture information. The detail in a larger image does not exist, in reality.    Technion scientists had studied  the problem and developed an approach. This was in March of 2003. I recently ran across some work being done in the area of neural networks that expands the field.    A paper on SRGAN, images/videos and super resolution attracted my attention. SRGAN is:Super Resolution with Genrative Adversarial Networks.    This approach is very effective, though some failings in color occur. Structure and form are well done and the manufac...

Digital movies and editors -- do it yourself?

   Occasionally, I need to correct a delay in the audio in a video. I have become acquainted with all kinds of software for modifying and playing media such as movies, images, and music.    Sometimes a video will have an audio track that is not loud enough. I have a software to correct that problem.    I have installed and used video editors to convert from one file format or codec tro another. My preference, currently, is for Matroska containers using HEVC-x265 compression and AC3 or FLAC audio encoding. The Matroska file trype can contain separable subtitles and audio in several languages. Separable means one or more of any can be removed from the file. All excess language audio tracks and subtitles can be removed for local use. This saves some on disk space.    I have several Apple iPhones. Sometimes, I use these phones as movie cameras. I used one to make a movie of shadows on my solar panel array. I needed to study the play of shadows ...

Digital movies and database software

I've been spending a lot of time and energy on digital movies lately. I've acquired a collection and installed database software specialized for movies and or media in general.    There are many such programs available and I decided to find the better ones and put them to the test.    You would be surprised at the problems that can arise when the user context does not overlap the software use plan exactly. Anbother way of saying personal habits can result in problems if the program designer thinks differently than you, and narrowly.     Human factors engineering is important in software. Easy to learn and use software becomes popular if the program does what's expected well. People will pick an easy to use software over a difficult, obtuse, piece of software given all other thing are equal.    I used a DBM (Database Manager) that is popular and free. My problem was, the programmer wrote the program from the botom up, and not top down. T...

HDR : myths and misinterpretations

   I've become aware of widespread  disinformation on HDR. Reviewers of video products and software make claims based on an incomplete and faulty understanding of HDR.    HDR does this, HDR does that, HDR will do this and that.    Many such people do not understand the difference between an HDR image and the compressor that makes the image viewable and printable. The HDR is the attempted storage of  an aspect of 'reality'. This 'reality' is too much for computer displays and printers so someone writes compression software to make the HDR acceptable, i.e., viewable on monitors and printable on printers. There are an infinite number of ways to do this. The HDR image you see and like so much may have been compressed by a different method than the same HDR another person may see, resulting in two visually different images.    This boils down to a matter of interpretation. Much of what is being attributed to HDR images is really the effe...

HDR history

   As a precursor, let me reiterate, these blogs are for intelligent people with a university background and courses in mathematics, engineering, physics and other of the hard sciences.    The first HDR image was the result of the independent work of Prof. Paul Debevec, U.C., and Gregory Ward Larson, JPL.    Prof. Debevec developed an algorithm to composite several images into one. His work was published in a research paper still available online. In the back of the paper is a Matlab script of the algorithm. Matlab is published by Mathworks, Inc, and is the foremost mathematics laboratory,  Matlab is widely used by scientists and professionals in a science related field.    One of the unknown benefits in HDR is the ability two construct an HDR image with only two exposures (images) if the same film is used for several images. Prof. Debevec derived an additional algorithm for determining the film character and using that data to reduce the...

High Dynamic Range imaging

   High Dynamic Range imaging (HDR) has come some way since I first ran across the initial phenomenon in the late 90's. HDR is a file format for images that contains numbers. The numbers represent so much pictorial information, no monitor or printer can display the data in it's entirety. The HDR image is like a digital negative in as much as making a print involves adjusting the enlarger aperture and light source to an exposure level consistent with the photographer's goals. No one exposure represents the negative entirely. Lighter exposures reveal different details than a lower exposure.    An HDR image is formed by taking a series of images that vary only in shutter speed, and combining them in a defined way. Think of an unsliced loaf of bread as an image. T he several images represent every nth slice in a sliced loaf. The other slices are filled in using highly educated guesses to get a full, sliced loaf. Each slice represents a specific shutter speed.   ...

Film Scanning

   I for got to mention in my introduction to this blog, that film scanning would also be discussed. I inherited a large number of photo negatives from my father. These negatives range in dates from the late 1930's to the 1970's.    Fortunately, most of the film is in 620 format. This large format preserves more detail than smaller formats such as 35mm. The film subjects are of several types. Family photos before and after my father married my mother and photos from his time in the military, Army Air Corp.    I decided many, years ago, to attempt to digitize the images and store them on my computer. There was little technology and knowledge available on the topic then. Much more has developed, but what I discovered, remains to this day, as far as I know, the most advance process available. Unfortunately, I won't be able to share the details since my copyrights and patent rights are not protected. I will reveal much useful information though.