Thursday, November 01, 2012

View pictures on TV set

This post is partially out of sync with others. It is about how to convert digitized pictures for best viewing experience on TV screen. I hope at least some readers will find it useful.

The problem

Several days ago my daughter celebrated her 20th birthday. According to family tradition this means we invited everybody (grandparents, aunts and uncles and their families) to dinner. Since I had just finished scanning my slides, including those of my daughter from her birth until I started to use digital camera, I have decided to prepare a short “historical overview of her life”. It took me almost 2 hours to select approximately 100 pictures out of several 1000, but that is not the theme of this post.

Since computer screen is too small to show pictures to more than three people, I decided it would be better to use TV screen. But our TV set is an older Samsung; it has several input connection possibilities, including USB port. Theoretically, it can show JPG pictures from USB stick, but its software is so stupid, that it does not keep the aspect ratio, but always shows them full screen. Landscape orientation pictures are changed from 4:3 to 16:9 making everybody on them appear so fat, that I do not dare to show it; and you can imagine, what happens to portrait pictures.

My first idea was, to create a film (of course the Samsung has no problem showing films in correct aspect ratio, otherwise nobody would buy it). I have a friend, who is creating such film presentations from old pictures all the time, including the music and image transformation effects; I thought, if he can, so can I. So I searched the net, downloaded several programs that were supposed to be able to do it and tried them. I expected to be able to do something like: select a folder with JPGs (pictures), select transition effect, select how long to see each picture and let it create the AVI (film). After an hour I had nothing usable, either I was not able to guess how to do it or the result was a disaster. OK, I confess, I did not RTFM of any program I tried.

The solution

While seriously considering reading some instructions I have got a better idea. I could resize all the pictures to 16:9 by adding some black border, so the Samsung won’t spoil the aspect ratio. With any of the programs I use on Windows or Linux to edit pictures it is an easy task to manually resize a picture. But I had 100 pictures and I am lazy, at least when such boring repetitive work is required. Most programs also support some kind of batch processing. On Windows my favourite for basic image editing is IrfanView. It is fast, small and free, and you can do batch processing. If you do not have it yet, download and install it immediately! I mean it, do it now, before you continue to read!

I was 99% certain (only because in computer sciences 100% certainty simply does not exist as something can always go wrong) that with IrfanView I can resize all the pictures with one batch. But before we continue to how, let’s first exactly define what the target is. As everybody probably knows, the HDTV (or 1080p) standard supported by all modern TV sets has the width of 1920 and height of 1080 pixels. My sources (the scanned pictures) were approximately 4900 * 3200 pixels if landscape or vice versa if portrait orientation. I have decided to create a downsized HDTV copy of all pictures (ignoring the orientation) using next 2 steps:
  • resize the height to 1080 while keeping the aspect ratio.
  • add black border on the left and right sides to get the width of 1920 pixels.
This transformation results in big information loss (approximately only every tenth pixel is retained), but the TV set can’t display more anyway. So it is only the choice of what software to thrust to calculate the downsized picture, IrfanView or TV set. As already explained my old Samsung TV’s software is not a good choice, but even relatively new Sony TV that my parents own (it keeps aspect ratio correctly) needs several seconds calculating downsized picture, before it displays it.

So here is what you came here for: the detailed instructions how to use IrfanView to batch process a lot of pictures for best viewing on HDTV. First using Windows Explorer create a source folder containing all the original pictures you want to transform and an empty target folder, where converted pictures will be saved. Go to source folder and open the first picture in IrfanView (if IrfanView is chosen as default picture program just double click the first picture).

A) In menus select File / Batch Conversion Rename (or simply press B on the keyboard)
B) Under “Work as” select Batch conversion
C) Under output format select JPG and click button [Options]

D) Slide quality to 100 and click [OK]
E) Select Use advanced options and click button [Advanced]
F) Select RESIZE, Set new size, Width: (empty), Height: 1080 pixels
G) Select Preserve aspect ratio and Use Resample function
H) Select Canvas size and click button [Settings]

I) Select Method 2, enter Width 1920 and Height 1080
J) Select Center and click [OK]
K) Another [OK]

L) Under output directory click Browse and select created target folder
M) Click button [Add All] (or use other buttons) to select pictures for batch processing
N) Click button [Start Batch]

In a minute or two, hundreds of JPGs are converted to a perfect HDTV size. Use Windows Explorer to copy JPGs from target folder to USB stick and show them to friends or family. Besides having correct aspect ratio on any TV set there is an additional bonus. Because TV set does not need to recalculate the picture size, they are displayed instantly.

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