Play a folder of images on a TV as free signage

What is the free way to cycle a folder of images on a TV?

For one screen, the free path is the folder slideshow your equipment already has: the mini PC's photo app cycling 1920 x 1080 images at a 30 second dwell, or the TV's own photo mode fed by a USB stick.

Both cost nothing because the slideshow is a feature, not a product. The shortlist, in the order to try them:

1. Folder slideshow on the mini PC. The photo app already installed runs any folder as a slideshow, and the interval is adjustable, so 30 seconds is a setting.
2. The TV's photo or ambient mode. A USB stick or an online album, and no PC left running.
3. A card-fed signage display. Files live on a card in the screen; updates are a card swap.

Two numbers run the whole job: the slide size, which is the screen's resolution, and the dwell, the seconds a slide stays up. A folder of 10 slides at a 30 second dwell makes a loop of 10 x 30 s = 300 s = 5 minutes. Everything else in this article is those two numbers plus housekeeping.

How big should each slide be in pixels?

Size every slide to the screen's pixel grid: 1920 x 1080 for a 1080p TV in landscape, 1080 x 1920 in portrait. A file at that exact size fills the panel edge to edge with nothing scaled or cropped.

A file at any other size gets scaled by whatever plays it, and scaling is how slides end up shrunk into one corner with black around them; that failure has its own write-up at signage slides that sit in one corner: fix the size mismatch. Portrait mounting flips the export to 1080 x 1920, and the preparation is different enough that preparing portrait signage images for a mounted screen is its own guide.

Text size carries its own rule of thumb. The FHWA lettering rule allows 30 ft of viewing distance per inch of capital letter height, with 20 ft per inch the safer figure for fast reading. At a 12 ft lobby viewing distance that is 0.4 in of capital height at minimum, 0.6 in for comfortable reading. The worked example below converts those inches into pixels on a real 40 inch panel.

How do you set up the folder slideshow on the mini PC?

The photo app on the mini PC runs a slideshow straight from a folder, with an adjustable interval, and that is the whole setup: point it at the folder, set the 30 second interval, and turn off every power timer that blanks the display.

In full:

1. Export every posting from the design tool at 1920 x 1080: PNG for text-heavy slides, JPG for photographs.
2. Collect the exports in one folder on the mini PC and share that folder on the network, so the content person drops new files in from their own desk.
3. Point the photo app's slideshow at that folder and set the interval to 30 seconds. Leave shuffle off unless the order should vary.
4. Turn off every timer that blanks the display; the sleep section below has the checklist.

If a fresh export does not show up in the rotation, stop the slideshow and start it again. The folder is the only source, so nothing else needs re-exporting or renaming.

Can the TV run the slideshow without the PC?

Yes. A smart TV's ambient or photo screensaver mode cycles an album from a USB stick or an online album at the panel's full 1920 x 1080 with no PC attached, and you reach it through the TV's settings, under its system menu.

Two ways to feed it. Copy the folder to a USB stick and point the photo mode at the stick. Or upload the pictures to an online album and point the TV's ambient mode at that; on such TVs the path runs Settings, then System, then Ambient mode, and the Source setting picks the album. Set the dwell if the mode offers an interval; dwell and ordering choices are whatever that mode provides, and an update means copying a new stick or uploading a new album.

The limits are the trade for zero hardware: no schedule beyond the TV's own timer, and no publishing from the designer's desk. For a lobby notice board that is often enough. One trap to check: a TV playing from a USB stick can run into its own sleep timeout, which has a step-by-step fix in keep a TV slideshow running: stop the USB sleep timeout.

How does a free folder slideshow compare with a subscription player?

Folder slideshow, TV photo mode, card-fed display and subscription player each cover the same one-screen job; the free paths give up remote publishing and per-screen management, which is exactly what a monthly subscription per screen buys.

Where each wins:

• The folder slideshow wins on cost and control: dwell and order fully set by you, updates are file drops, nothing new to buy.
• The TV photo mode wins when no PC should be left running; the screen already on the wall does the job from a stick.
• A card-fed display wins when the TV is due for replacement anyway. Our lobby displays play the same images from a card, offline, with no subscription.
• The subscription player wins once the job outgrows one folder: per-slide timing, scheduling, and publishing from the designer's own tool. The freemium, open source and DIY middle ground is compared in free digital signage software: freemium, open source or DIY.

Worked example: how many slides fit a five minute lobby visit?

A five minute lobby visit covers 10 slides at a 30 second dwell, because 5 minutes is 300 seconds and 300 divided by 30 is 10; a folder of 12 slides needs 6 minutes to come round once.

Scenario: a community room hangs one 40 inch 1080p TV behind the counter, residents read it from 12 ft away, and the board holds 12 postings.

Text size first. The FHWA rule gives 12 ft / 30 ft per inch = 0.4 in of minimum capital height, and the fast-reading figure gives 12 ft / 20 ft per inch = 0.6 in. A 40 inch 16:9 panel stands about 19.6 in tall, so 1080 pixels / 19.6 in = about 55 pixels per inch. Minimum capitals: 0.4 x 55 = 22 px. Fast reading: 0.6 x 55 = 33 px. Set body capitals around 35 px and headings around 60 px and both targets are met.

Timing next. Twelve postings at a 30 second dwell make a loop of 12 x 30 s = 360 s = 6 minutes. A resident sitting for 5 minutes sees 300 s / 30 s = 10 slides, so 2 of the 12 postings never appear during that visit. The fix is arithmetic: cap the folder at 10 slides, or keep all 12 and cut the dwell to 25 s, since 12 x 25 s = 300 s = 5 minutes exactly.

How do you stop the screen sleeping mid slideshow?

Sleep timers are the reason folder slideshows die at 2 a.m.: the PC's power plan or the TV's timer blanks the display, so set the PC to never turn the display off and check the TV's own sleep timer too.

Three timers to chase. On the PC, the power plan's display-off setting and the screensaver wait both blank the screen; set the display to stay on while the lobby is open, and let the slideshow itself act as the screensaver so the two settings cannot fight. On the TV, check the sleep or auto-off timer in its settings; an ambient mode is the screensaver itself, so nothing underneath it blanks the picture, but a TV fed over HDMI from the PC still obeys the TV's own timer. A card-fed display sidesteps the lot: the player keeps its own daily on and off times, shows black at minimum brightness outside them because the app cannot switch the backlight off, and brings the show up full screen at power-on with no launcher and no keyboard.

When is it worth moving to a cloud player?

Two things justify paying: a second screen, and updates the designer publishes from their own tool to screens they cannot reach. With one screen and files dropped into a folder, the free 30 second slideshow is the right answer.

Trigger one is a second screen. A folder slideshow lives on one PC; a second screen means a second PC or a different architecture, and that is where per-screen management in a subscription player starts to earn its fee. Trigger two is publishing: when the person making the postings should push changes from their own tool to a screen across the building, that is a cloud player's whole job. The full trade-off between local files and cloud accounts is laid out in offline or cloud signage: how to choose.

Before buying anything per screen, check whether one player can feed several screens: one signage player driving multiple displays covers that case. And if the screens will one day leave the building, planning a remote signage content workflow shows what changes when updates travel over the network instead of a shared folder.

Recommendation: Keep the free folder slideshow on the mini PC while the job is one screen, 10 or fewer slides and updates that arrive as dropped files: 1920 x 1080 exports, a 30 second dwell, power timers off. Move to a subscription player when a second screen or designer-side publishing becomes routine. If leaving a PC running is the annoyance, retire the TV and the PC together and put up a card-fed lobby display that updates by card.

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