Sunday 30 January 2011

Digital Artifacts - are they still around?

Well, first we have to address the 'artifact/artefact' debate. It seems that initially in the UK we accepted both forms of spelling to mean made by man, but then when it was transposed to the digital domain it meant the errors that cropped up in digital production of image and sound. But in the US they preferred the spelling artifact. Now digital artefacts owe more to the archiving or production of digital items made by people while digital artifacts appear to still denote the errors in digitising or processing! That's our interpretation - any comeback? (We've seen the same with program and programme, which now have different meanings.) So, can you pass the test below? Would you be able to identify digital artifacts if you saw them? Can you visualise or hear the errors below?

Image file possible errors: Staircasing (aka jaggies), Blocking, Posterisation, Incorrect colour/gamma
Movie file possible errors: Smearing, Pulsing, Low contrast
Sound file possible errors: Whistling, Quantisation noise, Burbling

Not an exhaustive list but at the end we'll have a quick run through the list with effect and possible cause These are only some of the artifacts around and as the inherent quality of digitisation improves – eg more bits for audio and higher definition for video, with better compression algorithms and more bandwidth available for the result, the errors are getting less noticeable.

Rather than generating your own errors in production now, because they are better understood and catered for than they used to be, you're likely to run into problems with files that your clients give you and insist they have integrated into their digital project. They may be 'left over' from the previous version of the web site. Did you build in leeway on time and money for any consequences arising from difficulties with the content provided by your clients? Andy's golden rule is always to get the highest quality original but sometimes it just doesn't exist. It isn't only getting copy from them that can prove difficult. More food for thought!

And so to the results ...
Staircasing
Diagonal lines don't look smooth, rather they seem to go up or down in steps. This is usually caused by inadequate resolution and/or antialiasing of the image. Often it's that there are not enough pixels to exactly represent the line and appropriate blending of the edges of line with the background has not been done to compensate.
Blocking
Areas of the image that should show smooth and gradual changes in tone and colour break up into square blocks of pixels. This is usually caused by trying to compress the picture (eg with JPEG or MPEG) too much.
Posterisation
What should be smoothly varying areas in the image actually look as if they have contours, like a map. This is because the difference between the adjacent areas of colour is enough for us to see. This is a problem compounded by our ability to detect the edges between the different colours very well. This used to be a big problem with 8-bit colour images but is less so with full colour ones, but it can still occur, especially if any processing of the image has reduced the tonal range. The answer is to diffuse the boundary with noise, a technique called dither. This is a reason why noise in an image can sometimes be helpful.
Incorrect colour/gamma
The image you see in Photoshop looks different to the one in your browser. The probable reason is that the colour profile information in the image is missing or incorrect. It's also possible that the browser doesn't obey it. (If in doubt use sRGB colour space.)
Smearing in a movie
What I mean by this is that when the camera pans across something like a grass field and then stops panning, the smeary texture of the grass suddenly clicks into shape and you can see the blades of grass. Although MPEG compression of video has a mechanism to allow for movement in the image it does have limitations. Basically, more bandwidth or a better codec are needed. This effect can be made worse by some LCD screens.
Pulsing
In a static scene the background seems to have slight pulse to it. Early MPEG encoders could suffer from this but it is much less common now. The usual cure is to adjust the space between the I-frames and many codecs will do this automatically for you.
Low contrast
With professional video that is re-encoded for the web you sometimes think the image has the contrast turned down. This may be because the codec used to produce your web version 'did not know' that black and white are not at zero and 255 in professional video. Your codec should allow you to adjust the black and white points to fix this.
Whistling sounds in an audio file
This is an aliasing problem. The original digitising of the audio failed to filter out high frequencies that were beyond the bandwidth of the sample rate chosen, this usually results in a whistling noise that comes and goes with the sound. Sometimes an inaudible high-pitched tone can mysteriously appear at a lower frequency in the digitised file as a result. You may be able to filter this out but usually you should go back and re-digitise.
Quantisation noise
Normally background noise in an audio file is a constant hiss but occasionally you can hear a cracking or hissing noise that seems attached to the sound and only appears underneath it. This will probably be noise caused because the number of bits in the digitisation is not enough to represent the sound. While this used to be a serious problem with 8-bit audio is is hardly a problem with 16 and more bits. However, it can occur with quiet sounds and some codecs will introduce noise into the process to hide this: dither again.
Burbling
You'll notice this mostly on music, where a long musical note seems to have a regular burble in it. This means that at some point in the process the sample rate of the audio has not been set correctly and the playback is compensating by adding or dropping bits. I hear this a lot on low-bandwidth digital TV channels.
Some places to see more information:
  • DP Review has a good technical glossary covering these and other still image issues.
  • An EE Times paper called Solving digital image artifacts with advanced video processing by Phuc-Tue Le Dinh and Jacques Patry is five years old and somewhat technical but covers video and is still current.
  • That Dither Thing is a paper by Werner Ogiers that is again technical but includes a dramatic demonstration of how dither can 'rescue' a 4-bit audio file.

Wednesday 19 January 2011

Open => Movies

A friend in Canada sent me a DVD at Christmas. It was a little different to your average DVD in that it contained another example of an open movie, and a very fine one too. But it's an open movie with a cautionary tale attached.

I'll get the good stuff out of the way first. It's called Sita Sings the Blues and tells a story from the ancient Hindu epic, the Ramayana, about the failure of Sita's marriage to Rama and its aftermath. This is juxtaposed with the breakup of another marriage; that of the film's maker Nina Paley. Sita is a goddess separated from her beloved Lord and husband Rama. Nina is an animator whose husband moves to India, then dumps her by email.

It's an amazing film; moving, witty and beautiful. It also includes some lovely music, most notably songs sung by a lady named Annette Hanshaw, on shellac 78s from the 1920s and 30s.

Nina has released this movie under a Creative Commons Attribution-Share Alike licence. As she says on the movie home page, "From the shared culture it came, and back into the shared culture it goes." The reason I'm mentioning it here (other than that I really want you to watch this movie) is to remind you of how convoluted and counter-intuitive copyrights can sometimes be ... especially in music.

Those of you who have been on our course or read the book will no doubt recall that I explain that a recording of a song contains two different copyrights; one for the recording and one for the song itself. In most cases the copyright in a sound recording expires 50 years after it is first published but that other copyright continues until 70 years after the death of the longest-lived composer or lyricist. Nina wasn't aware of this until after she had completed the movie and had to apply for licences from the music publishers retrospectively even though the recordings were out of copyright; never an easy task. She achieved this but it cost her - personally - $50 thousand. The publishers, on the other hand, may have been tied into contracts with their composers that restricted their room for manoeuvre (although they did drop their original fees from over $200K!). I should also add that including music in a movie or TV program involves a thing called the synchronisation right, which is different from the mechanical right which allowed the recording to be made in the first place, and the performance right which would allow it to be played in public.

So Nina has paid personally to allow us to download or stream the movie for our own personal use. It's right there up to 1080p HD resolution ... donations accepted.

While we're discussing open movies, have I mentioned the Blender Foundation to you before? Blender is a very powerful open-source animation package. Someday I really want to get to grips with it. The organisation behind it - based in free-spirited Amsterdam - have made some movie 'shorts' to show it off. There are three so far and they are also really worth a look. They are released under another Creative Commons licence, this time the Attribution one. Elephants Dream is a surreal journey inside a giant machine, Big Buck Bunny is Rambo meets Disney (sort of) with rendered fur ... and Sintel is a cautionary tale about a search for a pet dragon (with fast action). Each movie tests another feature of the software.

You can find the three on Blender's Open Projects page.

My and finally is to ponder whether there is a way of explaining the intricacies of intellectual property (like copyright) so that anyone stands a chance of understanding it. Now that almost everyone is using and creating and publishing (over the internet), rights are no longer something for experts and companies: they directly affect everyone. Maybe we need some kind of Highway Code for copyright. What do you think?

Friday 14 January 2011

Business cases and social media

It's been hard enough to make business cases for the other forms of interactive projects we're engaged in, but the move into social media has made it harder – why?

Well, yes, we're dealing with what have been called intangible benefits and traditionally these soft issues have not formed a core part of the business case mix. However as interactive technology has become more individual more mobile and more location sensitive, personal preference personal recommendations and personal opinions have more clout on the bottom line. We know this but how can we be convincing when making a case or pitch for a new social media project?

I imagine some of you are saying that it doesn't seem to matter as clients are just falling over themselves to get a presence in the social media market because they realise it is influential beyond expectation. But if you don't work with them to define what they expect from your offering for a time and cost, they may well have inflated expectations and you'll disappoint them. Now, disappointing clients is not a good option and certainly militates against return business, as we know.

Immerse yourself a little in some ideas from people trying to convince their own organisations to use social media. These people know they have to present strong business cases in terms that management will accept. Katy Cowan in Getting buy-in of social media, 11th January 2011, gives good tips for people trying to influence their companies that should make sense to you too. Jon Jackson, The Business Case for Social Media – stop being so analytical, 29th December 2010 gives equally sound advice despite riling against people that try to over-analyse the benefits. Don't miss Daniel's comment on this blog because whoever he is, he probably gives the best tips!

If you are having problems inside your own interactive company or section, why not get your lot to invest in the Social Media and Online PR Business Case, econsultancy Report, January 2010. It might be a little dated now in this fast-moving field and look expensive at £250 for 14 pages, but they have an offer of getting total access to all 350 reports for a year for £50 more. Maybe your management would accept this spend as an investment in training for employees? Keeping abreast of your field is Continuing Professional Development (CPD) after all.

Friday 7 January 2011

Creative working and Project Management Software

A few years ago, it was hard to find anyone in traditional Project Management who understood why working in digital media creative companies was different. The difference lay in the workflow: work allocation, flexible resources, variable costing, changing markets, clients demanding ongoing revamps, work starting before written approval and so on. After all, traditional project management is all about control while creativity doesn't like control. No wonder there were clashes.

But once creatives started demonstrating that their workflow was different and that project management software didn't quite fit, software was developed specifically for creative companies - often by creatives themselves. Well, after a shaky start, this has come of age. Now there are choices of software to suit digital creative companies. We thought it was high time to revisit this aspect of project management. If you have tried and given up on traditional PM software solutions, why not appraise some of these creative solutions instead? They may well offer a better fit for your way of working.

The most well-known and (informally) endorsed project software for creative working that we've come across is Basecamp. It prides itself on being very easy and intuitive to use, and it started from the project communication process rather than from the chart / stats angle. It is a good way to get employees into the concept of project management but may need progression afterwards (See Copper below).

Workamajig is an integrated system from task to accounting – and says it's Mac friendly too. Used by mainly by ad agencies, it is customisable for size of company as well as functionality.

Proworkflow is a hosted service that has 3 different plans for different sized solutions. It is also an integrated system that covers several of the main company functions.

Gantter is a FREE web-based PM tool. Ryan Dube endorses it in Oct 2009 MakeUseof.com where he enthuses over it and compares it to Microsoft Project. The files from Gantter are compatible with Microsoft Project too. Also tipped on Google Apps Marketplace as in the top 10 PM Apps in 2010.

Timefox aims at Freelancers and is more of a Timesheet and task tracking system. Monthly payment per users.

Copper is the one to watch! This might be the progression after your employees take to Basecamp. They focus on saving your company time and therefore money by better project control. They say they save between 20 and 100 hours for you a month!

Better project management for your company sounds like a good New Year's resolution! Now even creative companies can't just turn their backs on the opportunities.