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Monday, 24 September 2018

Recursion For Programmers


Recursion is a powerful programming technique. A function that calls itself recursively not only saves programming effort and avoids repetition but it can also be used to navigate complex structures such as Trees and Class Hierarchies. But recursion can also be quite hard to understand.

I recently published a course that explains recursion from the ground up. The full price is $45. But if you use the link below you can sign up for just $12! (Local taxes or EU VAT may be applied)
https://bitwisecourses.com/p/recursion-for-programmers/?product_id=778235&coupon_code=BWRECURSIONDEAL

I’ve tried to explain recursion in depth in this course. Along the way, I also explain some important details of the computer architecture. You need to understand the stack, stack frames, variable scope and a few other details in order to get a good understanding of recursion.


I strongly advise you to try to write our own recursive functions as you progress through the course. My examples are all in C, Ruby or C#. But you can write recursive functions in whichever language you happen to be using. In fact, it would be a good exercise to try to translate my examples into another languages – Python, Java, Basic or Pascal, for example.

The courses includes numerous short sample programs to show how recursion works. There are samples written in C, Ruby and C#. However, you don’t need to program in those languages to follow this course. Recursion works the same way in all mainstream programming languages. This course explains the theory and the practice of recursion. You can use the techniques that are taught to write recursive functions in whichever language you prefer: C, C#, Java, JavaScript, Python, Basic, Pascal and others. The course is not about any specific language.

This is what you will learn…
  • What is recursion?
  • How variables are scoped in recursive functions
  • How recursive functions return values
  • The Stack and Stack Frames
  • Debugging recursive functions
  • Recursion v Iteration
  • Stack Corruption, and how to avoid it
  • Infinite Recursion, and how to avoid it
  • Recursing Fibonacci Numbers
  • Recursing a Class Hierarchy
  • Trees and recursion
  • Navigating subdirectories recursively
Here are two sample lessons from the course…




Sign up before the end of October 2018 to get this course at a 73% Discount...
https://bitwisecourses.com/p/recursion-for-programmers/?product_id=778235&coupon_code=BWRECURSIONDEAL

Monday, 17 September 2018

Vegas 16 Edit Review

VEGAS PRO 16 Edit £299
https://www.vegascreativesoftware.com

VEGAS is a powerful video editing package which has been given a new lease of life since its acquisition by MAGIX Software in 2016. In fact, VEGAS 16 is the third major release in just two years.

VEGAS Pro 16 - a powerful package, though it takes a while to learn
New features include improved video stabilization and motion tracking, 360-degree video support (assuming you have a suitable 360-degree camera!), a ‘tiny planet’ plugin that distorts a video using an extreme fisheye effect to make it appear that the ground-plane forms a planet-like sphere, plus various user interface improvements.

Using 'tiny planet' I've transformed an ordinary field into a little world!
Plugins and effects can be ‘chained together’ by adding one plugin after another. The advantage of this approach is that you can selectively tweak numerous different parameters for each effect to give you precise and accurate control over each of them. The disadvantage is that this process can be time-consuming and confusing. For example, it may be entirely possible to remove background noise from a track using the Audio Restoration and NoiseGate effects (plus others) but working out how to do so can be baffling. Personally, I find it simpler to process audio tracks using some other tool such as the free Audacity audio editor or MAGIX’s own SoundForge program.

Here I've made a selection so that I can 'track' a person's movements
Video Effects can be similarly non-obvious. For example, to apply Motion Tracking you need to use a tool called ‘Bezier Masking’, then draw out a selection box over an object, expand a ‘Mask’ option in a dialog and finally click a button to track the object. If I hadn’t seen the MAGIX tutorial on this, I can honestly say I’d never have guessed that this was how to do it.

The newly enhanced Motion Tracking feature includes the ability to select objects (such as a person or vehicle) and automatically track their motion as the video plays. Masks and effects (blurs, contrast/brightness and so on) or text annotations can be added to the tracked objects to follow their movements. A very useful tool.

It’s worth saying that VEGAS has pretty much all the features you would expect from a pro-level video editing package: the ability to cut, trim, copy and move clips over numerous tracks in the timeline; a large range of transitions and effects; zoom, pan, add titles and so on.
For a more detailed overview of the code features of VEGAS, see my reviews of VEGAS Pro 15 and VEGAS Pro Edit 14

For those of you who use storyboards (a view of clips arranged either as lists or as sets of thumbnails arranged in lines like the rows of a spreadsheet) the new interactive storyboarding options will no doubt be welcome. This lets you make edits to the storyboard clips (e.g. changing the start and end points) or in the timeline (e.g. moving a clip to a new position) and the changes are synchronized in both the storyboard and timeline. 

If you want to change the colour temperatures and densities to emulate some Hollywood films, you can use the new Autolooks filter. The names of the preset options (‘Losing Private Brian’, ‘Nade Gunner’, ‘The Wobbit’ etc. may give you a few clues as to the sort of look these try to achieve).

Autolooks lets you change the colours instantly (no, the sky wasn't really that colour!)
At a more mundane level, the file saving options have been improved so that your projects and backups can now be auto-saved at user-selected locations at timed intervals or after every editing change.  For a more detailed overview of new features, including demo videos, see here: https://www.vegascreativesoftware.com/gb/vegas-pro/new-features/#productMenu

Overall this is a good new release of VEGAS Pro. It incorporates a range of useful improvements without sacrificing the familiar workflow of previous releases. Bear in mind, however, that while VEGAS is a powerful package, it is not the easiest video editor for a complete newcomer. But for serious video editing at a modest price, VEGAS Pro 16 is a damn’ good choice.

NOTE: Vegas Pro 16 is available in several editions which include additional features, at higher prices. See the product comparison table here: https://www.vegascreativesoftware.com/gb/vegas-pro/product-comparison/#productMenu For my reviews of other video editing packages, see HERE.

Wednesday, 18 July 2018

I Know Your Password - now let me blackmail you!

I know XXXXXXXX one of your password. Lets get right to purpose. You may not know me and you are probably wondering why you're getting this e-mail? No one has paid me to investigate about you.
I just received an email that started with the above text. Actually, the email was put into my Spam bin but I was browsing through when I noticed that the email header was quoting a genuine password that I have used in the past. "That's odd," I thought. So I read on. This is how the email continued...
In fact, I actually setup a software on the adult streaming (sex sites) website and there's more, you visited this web site to experience fun (you know what I mean). While you were viewing video clips, your browser started functioning as a Remote control Desktop that has a keylogger which gave me access to your display screen and web cam. 
Immediately after that, my software obtained all of your contacts from your Messenger, FB, as well as e-mail . After that I created a double-screen video. 1st part displays the video you were watching (you've got a nice taste rofl), and next part displays the recording of your webcam, & its u.  
You actually have 2 possibilities. Lets go through these possibilities in particulars:
First alternative is to just ignore this email. In that case, I most certainly will send your recorded material to every one of your contacts and thus consider regarding the disgrace you will definitely get. Not to mention if you are in a loving relationship, just how it will eventually affect? 
In the second place option would be to compensate me $3500. Lets name it as a donation. In this scenario, I most certainly will without delay erase your videotape. You can continue on everyday life like this never occurred and you surely will never hear back again from me.
You will make the payment through Bitcoin (if you don't know this, search for "how to buy bitcoin" in Google).
BTC Address to send to: XXXXXXX
[CASE SENSITIVE copy & paste it] 
In case you are looking at going to the authorities, surely, this e mail cannot be traced back to me. I have taken care of my actions. I am not looking to ask you for money a lot, I want to be paid for. I've a specific pixel in this e mail, and right now I know that you have read through this email message. You have one day to make the payment. If I do not receive the BitCoins, I will, no doubt send out your video to all of your contacts including family members, co-workers, and so on. Nonetheless, if I receive the payment, I will erase the video immidiately. If you want proof, reply with Yeah! and I will certainly send your video recording to your 5 contacts. This is the non-negotiable offer, that being said do not waste my personal time and yours by replying to this email.
OK, so this is a scam but it's a pretty interesting and deceptive one as it relies upon the receiver having more technical literacy than many simpler ("I'm a Nigerian prince, I want to send you money") scams. It assumes a) that you recognise your own password and know that other people should not have access to it and b) that you know what a keylogger is (it records and sends back to the bad guys the keystrokes you enter on your computer). It also assumes you understand Bitcoin and may at least be sufficiently baffled by the "hidden pixel" guff to think it's genuine.

OK, so I tracked down the password it mailed me. I had used it once, many years ago, when logging into a very innocent-looking site all about foreign language learning. The chances that a keylogger recorded my password all those years ago and the bad guys have only now decided to blackmail me seemed remote. Much more likely that the security of that site has been compromised, the bad guys got a whole load of old passwords and the rest of the email is pure nonsense.

Sunday, 15 July 2018

MAGIX VideoPro X 10 – review

https://www.magix.com/us/video/video-pro-x/ $399 / £299

According to MAGIX, “On the occasion of the software’s 10 year anniversary, MAGIX Software is introducing the largest update for Video Pro X ever to the market.” Well, let’s see if the software lives up to that claim…

Video Pro X is a Windows video editing package that lets you create movies from multiple video and audio clips. You just add the clips to tracks on a timeline, cut, trim, move and edit the clips, add effects and transitions if required, then export in a variety of video formats. There are, of course, lots of other video packages that do his. So what sets Video Pro X apart from the competition?

Video Pro X 10 is a good all-round video recording and editing package. You can see its multi-track timeline (below), video preview (top left) and tabbed panel of effects, templates and transitions (top right).
Well, for one thing it has a neat, easy-to-use environment. You can preview the video in two screen simultaneously so if you apply effects you can easily compare the clip ‘before’ and ‘after’. It has a good range of colour grading and ‘shot matching’ capabilities to let you change or regularise the colour temperature across one or more clips. It has a built-in audio editor to let you improve audio, remove background hiss and so on. It can auto-align multiple video and audio clips so that audio is synchronized (if, for example, you are editing video recorded simultaneously by two cameras). It even comes with a fairly powerful screen recording tool so that you can make screencasts with or without camera-recorded video overlays. In short, it has a range of features that make it suitable for most common video editing tasks, with a relatively low learning curve and at a modest price. See my reviews of the previous two releases: Video Pro X 2017 and Video Pro X 8 for more details.

Now let’s consider the new additions. One of the big improvements is the speed of producing finished videos. By making use of the NVIDIA graphic cards’ encoding hardware, Video Pro X says that it now exports videos at speeds “which were inconceivable in the past”. Other optimisations have been made to boost image processing speeds and 4K output quality.

If you are using a 360 degree camera, you will also be able to take advantage of new and improved features such as 360 degree image stabilisation and transitions. These are supplied via the include 3rd party add-in from HitFilm.

Another new feature is the grouping of J-L cuts (a technique for synchronizing video and audio across clips). User interface improvements have been made too.  For example, the effects panel has been redesigned (with lots of little grouped icons) to make it easier to find effects quickly.

What’s New?


Let’s start with the J-L Cut grouping. J-L Cut is a term that describes the ability to cut from one bit of video to another while keeping the audio track synchronized. For example, Person One is talking then you cut to show Person Two’s reaction you may want to keep Person One’s voice playing across both video clips, That’s an L Cut. On the other hand, if you Show Person Two’s face while we hear Person One’s voice, then switch to show Person One speaking, that’s a J-Cut. The names J and L refer (very roughly) to the shapes made by the clips on the timeline when you make these sort of edits.

When audio has been recorded ‘into’ a video clip you can either edit the video+audio on a single track or you can separate them so that they are shown on separate tracks, one above the other. In normal editing mode, when you drag the start or end edges of the video track, the edges of its associated audio track move too. With the J-L editing mode, you just hold down the ALT key so that when you drag the video clip, the audio track is unaffected. The audio remains synchronized with the video but the video itself can be easily cut to allow other video clips to be added over the audio track. While this sort of thing can be done in the standard editing mode, it is much faster and simpler using the dedicated J-L editing mode.

Another handy editing addition is the ‘move object contents’ mode. This lets you retain the clip’s length and position in the timeline but use the mouse to scroll to a different starting point of the clip. In other words, assuming you already have a 5 second clip (editing from a 60 second piece of video) of someone catching a ball but now you decide that you’d really prefer to have used a slightly later portion of the video clip showing the person throwing the ball. Usually this would mean that you would need to do quite a bit of re-editing to cut out a different bit of the clip and substitute it for the one currently in use. With the ‘move object contents’ mode however, you can leave your 5 second clip right where it is and use the mouse to scroll to a different part of the 60-second video, making the actual editing process very simple and quick.

The Chroma Key feature has also been improved in this release. This lets you select a small background area in a video clip and then automatically remove that colour from the clip. This is typically used with green or blue-screen backdrops to allow the video-maker to ‘cut out’ the speaker or actors from the foreground and then completely replace the background. Chroma Keying is routinely used in TV shows and movies to create composites in which separately shot foreground action is seamlessly placed into a background. Chroma Keying can be quite difficult to get right, however. Often the Chroma key leaves a green fringe around the foreground talent, or the edges may be raggedy. This can be particularly problematic when you are shooting in a small space, with the backdrop quite close to the actor (so some colour spill occurs) or when you are unable to light the backdrop sufficiently well to ensure a pure and consistent colour throughout. In such conditions, it may be hard to remove all the background without also removing some of the foreground. As long as your backdrop is very evenly illuminated, Video Pro X does a good job of background removal using sliders to make manual adjustments including ‘antispill’ (green fringe) removal.



Chroma Key lets you remove a background colour (the green here) so that you can substitute a different background image or video. It can be effective with really good green-screen lighting. But it’s hard to get a good Chroma Key effect when the green screen lighting is imperfect.

The Chroma Key sliders can be quite sluggish, however. Often they just don’t move at all or only move jerkily when I drag them. The problem could, in any case, be avoided if numeric input (percentage values) were provided as an alternative to the sliders. The other deficiency of Video Pro X Chroma Key is that it is a bit unforgiving when working with unevenly illuminated backdrops. As a lone video-maker, I rarely have the time or the space to set up a perfectly lit green screen. With imperfectly lit backdrops, getting a good key in Video Pro X is quite tricky. Some packages (such as the low-cost Movavi Video Suite) cope much better with imperfectly illuminated backdrops.

Speed


Finally, it’s worth mentioning the speed improvements when rendering the final movie. Video Pro X 10 can take advantage of the hardware capabilities of modern NVIDIA graphics cards to increase the rendering speed when exporting movies using the HEVC/H.265 MP4 format. This is said to be “the biggest leap in Video Pro X performance in years.”

I did a test render of a short project (2 minutes, 11 seconds in length) at 25fps and a resolution of 1920x1088. The project comprising several video clips and transitions and was rendered on an i7 CPU @ 3.30GHz, 16Mb RAM with an NVIDIA GeForce GTX 980 Ti with 6Gb graphics card.

The results were that it rendered MPEG in 3m36s with a file size of 459,674 and it rendered HEVC in 2m15s with a file size of 133,349. So clearly in terms of both exporting time and file size, the HEVC rendering is substantially better than MPEG. The relative improvements will, of course, be much more noticeable with bigger projects.

Video Pro X 10 can export movies in a number of different formats and a PC with a modern NVIDIA graphics card can take advantage of accelerated rendering speeds.

Now, benchmarks like this should be taken as only a very rough guide to actual performance. The results may vary considerably due to factors such as the complexity of the project (the media that’s included, the range of transitions and effects) as well as the exporting options selected. For comparison, I tried HEVC exporting a longer but much simpler project. This comprised a single 6m32s video clip with no effects or transitions at 1920x1088 and 30fps. The render time for this was just 1m38s. In other words, pretty damn’ fast. Even so, it was outperformed by Cyberlink PowerDirector 16 which rendered the same clip with the same settings, also using hardware video encoding, in exactly one minute. In fact, when I changed to my usual PowerDirector render settings (H.264 AVC/MP4, 1920x1080, 30fps using hardware video encoding) it rendered the movie in just 49 seconds. On the whole, it seems to me that PowerDirector still has the fastest video rendering of any package that I am aware of. Even so the hardware-accelerated speeds achieved by Video Pro X are good – significantly faster than many other video editing packages.

Conclusion


So, in conclusion, how good is Video Pro X 10? My view is that it is pretty damn’ good. I could certainly imagine using it for all my own video editing projects. Its speed, ease of use and its excellent range of editing and rendering features make it an accessible and powerful editing suite. That said, I’m not entirely sure why it is said to be the “largest update for Video Pro X ever”. Welcome though the additions and enhancements are, the range of improvements  is not quite as extensive as I had been expecting based on the company’s marketing claims. The interactive clip-editing and rendering speed optimizations are the two things that stand out for me. It’s a pity, though, that the Chroma Keying is not more able to deal, more easily and quickly, with less than perfect backdrop illumination.

Overall, MAGIX Video Pro X 10 is a solid, capable, well-featured program for recording, editing and producing good quality video. In spite of a few criticisms, my view is that this is an impressive pro-grade all-rounder at a reasonable price.

Tuesday, 10 July 2018

Paragon Backup & Recovery Free

Paragon Backup & Recovery Free is a newly-released PC backup and recovery tool from backup specialists, Paragon Software.

Key features:

  • Disk Backup – Save not only disk data but also system service structures
  • Differential Backup – Save backup storage space by archiving only what’s changed since the last full sector-based image
  • Incremental Backup – Back up modified data along with a full sector-based archive
  • Flexible Restore (in WinPE) – Restore an entire disk, separate partitions, or only the files you need from previous backup images
  • Recovery Media – Create a bootable USB Flash drive, CD, or DVD to recover your PC on demand
  • Easy Recalibration – Restore contents of a 512-byte hard disk to a 4K hard disk with no additional input from your side
  • WinPE-based Recovery Environment – Create a full-fledged Windows-based recovery environment stored on bootable media.

For more advanced data management functionality, the company offers Paragon Hard Disk Manager for Windows– an all-in-one data management tool combining the backup, recovery, partition management, data migration and data wiping technologies.

Paragon Backup & Recovery Free is available to home users at no cost at https://www.paragon-software.com/free/br-free/

Wednesday, 4 July 2018

Camtasia 2018 Review

Camtasia 2018 $249

(upgrade $99.50)

https://www.techsmith.com/

Camtasia is one of the best-known and best-liked screencasting programs for Windows and Mac. It gives you the ability to make video recordings from your computer monitor and edit them on a multi-track timeline. I reviewed the last major version of Camtasia (version 9) back in 2016. The new release, Camtasia 2018, adds on some new features and optimises some existing features. So let’s see what’s changed…

That’s Camtasia 9 in the background (top-left) and Camtasia 2018 in the foreground. At first sight, nothing much seems to have changed. You need to look more closely to spot the differences… 
One of the big changes, according to Techsmith, is the improved Library. The Library is a panel where you can store reusable assets – video and audio clips, backgrounds, animated objects, intros and outros and so forth. In Camtasia 9, the Library shared a tabbed panel with the Media clip panel. In Camtasia 2018 it’s been given its own panel with a few extra capabilities. For example, you can now have multiple named libraries, you can manage assets by moving selected elements from one named library to another, you can enter text to search for an asset and you can automatically import libraries from Camtasia 9.1. Well, up to a point. I found that the Library importer failed with my Camtasia 9.1 Library. It also failed when I explicitly exported the 9.1 Library and then attempted to import it. I got around this problem by selecting portions of the old Library, exporting those to a Library zip file and then importing them.

The Library now has its own dedicated panel (show at the left) and it it includes various assets such as the animated background that is being previewed here.
Some additional assets are provided with this release. And if you need even more pre-designed intros, outros, backgrounds and music clips you can buy access to 600,000 additional royalty-free assets for $199 a year.

User-defined theming is another new feature. This lets you define the colours and fonts to be used for elements such as text and speech-bubbles. Then, when you add an element to the timeline you can select a theme from the properties panel to apply the preset fonts and colours to it. There is no way to set a default theme, however – one that atomically applies settings to elements as they are used. There is a theme called ‘Default’ but even that has to be applied on an element-by-element basis.

Themes let you define colours and fonts so that they can be applied quickly to text and callouts
There are a few technical improvements and optimizations too. There is an option to render at a higher frame-rate than before. Camtasia 2018 supports up to 60 fps (frames per second) whereas the maximum for Camtasia 9 was 30 fps. The rendering efficiency has also been improved with Techsmith claiming a speed improvement of up to 50%.

Camtasia 2018 can render at up to 60fps. Previously 30fps was the maximum.
Naturally, Camtasia 2018 retains the features from its previous release. If you are not familiar with Camtasia, let me summarise briefly. The software includes a screen-capture tool that lets you grab images of your entire screen or a screen from a selected monitor, it can lock onto a single window or it can record a user selected rectangle on screen. It can simultaneously record from a webcam so you can overlay the screen recording with a ‘talking head’ video. It includes transitions to join together clips using blurs, fades and so on. It has ‘behaviours’ to let you add bouncing and sliding movements to clips or text. It has annotation tools to add highlights, boxes, arrows and speech bubbles. And it has a small but useful range of video and audio enhancement tools to remove background hums from audio, colours from video (for Chroma key/green screen effects) and so forth. For a more extensive overview see my reviews of Camtasia 9 and Camtasia 8.

I recorded myself in front of a green screen. By using the ‘remove a colour’ (Chroma key) option I was able to remove the background. This is not a sophisticated Chrome key tool but for ‘talking head’ screencasts it does the job quickly and pretty efficiently.

Final Thoughts…

So it’s been a two-year wait for this new edition on Camtasia. Has it been worth it? Well, I have to say that the software has changed very little since the previous release. The addition of 60 fps support is welcome and changes to the library and themes are also useful. But in all essentials Camtasia 2018 looks and feels just like the previous release. Arguably, of course, that is no bad thing. If something does a good job and users like the way it does it, why change it? Camtasia remains my preferred screencasting software on Windows. I also like the Mac version (especially its ability to swap recordings easily with the Windows version) though it has to be said that on the Mac, Camtasia faces stiff competition from Screenflow.

Even so, I am surprised that the existing features have not been expended to a greater degree. Why are there no extra transitions, video effects, audio effects, annotations and behaviours for example? If you already have Camtasia 9 and are wondering whether or not to upgrade, frankly, I would hesitate. Unless there is something among the new features that is a “must have” for your work, the $99 upgrade cost seems to me to be a bit steep for a product that has changed so little.

If, on the other hand, you are not an existing user and you considering buying a screencasting suite, well, in that case I would certainly recommend Camtasia. But bear in mind that Camtasia is a screencasting application that does ‘pure’ (camera-recorded) video editing as a bonus. If your main requirement is to create videos from camera recordings then you should invest in a general-purposes video editor such as PowerDirector. PowerDirector, and some other general-purpose video editing packages, also provide screen-recording capabilities. So if you don’t do much screen-recording a package such as PowerDirector might be a good all-rounder. But if screen-recording is your main requirement and you want a fast, simple and efficient package, Camtasia remains my first choice.

For more reviews of screencasting and video editing programs see here: http://www.bitwisemag.com/search/label/video

Monday, 18 June 2018

Able2Extract (PDF editor/converter) Review

Able2Extract Professional 12 $149.95
https://www.investintech.com/

PDF documents are everywhere these days. PDF documents provide a useful way of distributing files that retain all the formatting information from Microsoft Word, Excel or whatever other application you used to create the file. The problem with a PDF document is that once you’ve created it, it remains pretty much non-editable. Often that is what you want. But sometimes it can be a nuisance. For example, you may want to fix mistakes in a PDF document sent to your by a colleague. Or you may want to split a large PDF file into smaller individual documents. That’s where Able2Extract can help out.

Able2Extract can edit and convert large, complex documents including graphics and non-English (here Japanese) text
Able2Extract is a PDF editing and conversion tool. It lets you translate between PDF and multiple other common file formats. Conversion can be done in both directions – for example, you could convert from an Excel spreadsheet to PDF, edit it in Able2Extract, then save the resulting document to a Word file. Conversion can be done one document at a time or in batch mode on an entire directory of documents.

You can edit documents by adding and deleting text, adding graphics, redacting (blacking out passages) or adding annotation such as notes and strikethroughs. If you need create editable forms with interactive ‘fill-in’ fields you can do that too. There are limitations to the editing capabilities, however. If you expect to be able to edit text as you would in a word processor you will be disappointed. Editable text takes the form of pages, paragraphs, lines or parts of lines which can be edited within an area defined by a bounding box. Not only can the text inside the bounding box be edited but the entire box and its contents can be dragged and dropped to reposition it.

If you want to hide sensitive information from prying eyes you can ‘redact’ a document by replacing selected passages with black markers.
The actual areas defined by the bounding box are often unpredictable. In some documents, large blocks are editable, which is what you would expect. In other documents, seemingly arbitrary blocks are marked off as editable, and sometimes a single line of text is divided into several independently editable areas. Text edits ‘flow’ only within the confines of the bounding box, so you won’t get automatic word-wrap throughout an entire document as you would in a word processor.

This is the company’s official promo video

I’ve tested PDF import with a variety of different source documents and found that Able2Extract copes well even with documents containing Japanese text and mathematical formulae. Some characters, however, seem to vanish when a selection box is activated for editing. For example, in a mathematical expressions such as x(100) = 1 seem to vanish when the paragraph in which it appears is selected. I eventually discovered that this is because each part of the expression has its own selection box. So in the example above x has one box, (100) = 1 has another and the text of the paragraph in which it appears has yet another selection box. Obviously that makes the editing process rather tricky!

Here (above) I show the same part of a mathematical document with two different paragraphs selected. Note that some mathematical expressions (on the right) seem to ‘disappear’. This is due to the fact that they have their own selection boxes and so they do not appear within a selected paragraph.The conversion option is also a bit odd. You can’t just convert an entire document unless you first select all the text in that document. Selection before conversion makes sense if you want to convert only a selected block of text (and this is indeed an option) but it seems strange to insist that all the text be selected in advance of converting a whole document.
The Save As option is similarly restrictive. Sometimes I want to save a copy of a document before editing it, but the Save As option is only activated once editing changes have been made (otherwise it is greyed out).

There are, of course, numerous products available for viewing or editing PDF files (see Wikipedia for a list of some of them). If you just want to save from Word or Excel to PDF then the tools built into Microsoft Office are likely to be all you need. Some design and DTP applications also support PDF import (for example, the free LibreOffice suite imports editable PDF into its drawing application).

Adobe Acrobat, would once have been my first choice PDF editor. However, since Acrobat migrated to a subscription model costing around £13 a month for the basic version or £15 per month for the fully featured one, I am less enthusiastic. Personally, I hate subscription software. Even so, Acrobat is the ‘industry standard’ and if you don’t mind hiring it instead of buying it you can scan through the feature list here to see if it does everything you want: https://acrobat.adobe.com/uk/en/acrobat/pricing.html

If you prefer to buy a PDF editor outright, Able2Extract may appeal to you. Bear in mind though that you would need to verify that it provides the capabilities that you really need. To do that, I recommend downloading the trial edition before making a decision.