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Getting my library cards onto my phone the hard way

iliana.fyi

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Re: Getting my library cards onto my phone the hard way

#161

Post by lxgr »

jldugger wrote: post #117
lxgr wrote: post #76

Earlier quoted context omitted.

I mean, it's ultimately a bunch of pixels representing a barcode to be scanned. As long as it displays correctly, what could go wrong?

In the era before smartphones, barcode readers were highly tuned devices that emitted a specific frequency of light and the sensor was tuned for exactly that. Cellphone screens generally don't emit that frequency of red, and I guess absorb rather than reflect light sent to it, making the screen opaque. So even if you, the human, can read it doesnt mean the device that authorizes you can.

Definitely, but what I mean is that that's not a failure mode specific to Apple passes. If a screenshot a barcode works, so should the pass, and vice versa.

Re: Getting my library cards onto my phone the hard way

#162

Post by lxgr »

cglong wrote: post #112
skykooler wrote: post #56

Earlier quoted context omitted.

Library might not be open on a Saturday?

This isn't an unpublished zero-day, or even a new feature in iOS. I would've waited until Monday to publish if that was the issue.

The point of the article is to show how it's possible to create an Apple pass from a custom barcode.

Whether that barcode can then actually be read by a specific reader from a phone or not is arguably a different concern: Some readers support it; others don't. Obviously a passbook version of a paper barcode is useless for the latter.

Personally, I found the post valuable regardless of whether the barcode would actually end up working at the author's library or not; I have a few scenarios myself where I know screen-presented codes are accepted.

Re: Getting my library cards onto my phone the hard way

#163

Post by ta8903 »

ivlad wrote: post #135
fastball wrote: post #120

Earlier quoted context omitted.

Doesn't the Starbucks app literally do this for you? It did when I had it 7 years ago.

That would require granting Starbucks app access to your location, even when the app is in background. Why would you do that?

As opposed to giving Apple/Google access to your location.

Re: Getting my library cards onto my phone the hard way

#164

Post by samtho »

lxgr wrote: post #82
samtho wrote: post #43

I really love barcodes and barcode symbology for reasons I cannot fully explain. I even wore the npm module named ‘barcode’ which I desperately need to update. Fun fact about codabar, it is among the only barcode symbologies that can be implemented completely as a plain font.

Interesting, why is that? Due to character boundaries and encoded-character-as-symbol boundaries not overlapping for the other codes? And do you know if that was a conscious design choice?

I am unsure of the context in which codabar was developed, but I know it was originally made for dot matrix printers, maybe if you go back to how those worked, it lended itself well to monospaced fonts because we had a fixed number of “dots” per byte cell. It can be roughly thought of like a low-resolution LED screen display used at transit stations to display real-time etas. The purposefully low resolution can save on costs while being able to show legible text - but not much else.

Codabar was can be implemented as a font because the standard does not define specific start and stops symbols, instead it was developed as just a raw 1-to-1 encoding of character to pattern. It does not have check digits because it uses more space per symbol to handle error correction by making it very difficult to misread each pattern. The spacing (kerning) between each symbol is a different width ratio than the white bars found in each symbol.

Going back to dot matrix, it does appear that some early printers just had a grid of character “cells” in which the spacing between each cell was slightly more than a single “dot”, this probably explains the codabar quirk with 3 different space ratios (black bar, white bar, and inter-character quiet-space) and probably is the beginning of some further investigation into that topic.

Re: Getting my library cards onto my phone the hard way

#165

Post by monksy »

philistine wrote: post #91
monksy wrote: post #51

Earlier quoted context omitted.

This system really sucks because you can't just slide your wallet over the reader. It'll pick up your cc before your transit pass. The move to do tap based transit with cc s is pretty stupid as that cc s get replace far more frequently than transit cards. The only person this really benefits is new users to the system that haven't figured out how to get a transit card yet.

Transit authorities are really being hammered with lower ridership right now. Now's the time to get rid of all the friction that prevents usage, like requiring bespoke payment solutions that need prior preparation.

Well if they looked into why they're at low ridership.. they'd probably see that they're doing a poor job. (In the states)

I can't speak towards other systems but the CTA in chicago is having issues with:

1. Actually keeping a schedule [we've been lied to about wtih them adhering to their frequency schedule they advertisesd]

2. Safety in the trains [people are using the trains to smoke, drink, deface, start fights, and live there]

3. Being reliable. There are times where they just won't run for 20-40 minutes. That makes it hard to want to use it. But they're claiming "oh we don't have enough bus/train drivers" .. yet they haven't been doing anything about it and let people go during the lockdowns.

The ease of payment isn't really a big deal with people who live and depend on these the most. (They're the 80%+ of the ridership)

Re: Getting my library cards onto my phone the hard way

#166

Post by monksy »

modeless wrote: post #93
monksy wrote: post #51

Earlier quoted context omitted.

This system really sucks because you can't just slide your wallet over the reader. It'll pick up your cc before your transit pass. The move to do tap based transit with cc s is pretty stupid as that cc s get replace far more frequently than transit cards. The only person this really benefits is new users to the system that haven't figured out how to get a transit card yet.

Why does it matter if your credit card gets picked up before your transit card? If there's a discount or pass on the transit card, seems like the agency should let you attach it to your credit cards instead of requiring you to get a separate card.

Buying a month pass is a tax benefited account for commuting. [At many work places]. On top of that you have different pricing and you aren't paying full price at tap.

The CC being picked up means you're paying the full fare immediently even if you have the pass on the other card.

Re: Getting my library cards onto my phone the hard way

#167

Post by monksy »

LeafItAlone wrote: post #69
monksy wrote: post #51

Earlier quoted context omitted.

This system really sucks because you can't just slide your wallet over the reader. It'll pick up your cc before your transit pass. The move to do tap based transit with cc s is pretty stupid as that cc s get replace far more frequently than transit cards. The only person this really benefits is new users to the system that haven't figured out how to get a transit card yet.

> as that cc s get replace far more frequently than transit cards. The only person this really benefits is new users to the system that haven't figured out how to get a transit card yet. I respectfully disagree. I’ve lost more transit cards than credit cards. And since the tap-to-pay on credit card also works with Apple Pay and Apple has the ability to choose which card to apply transit charges to, it gets the same o…

How have you lost so many transit cards? I current have 4 iterations of transit cards for the CTA. I also still have many transit cards from my visits in different countries.

Re: Getting my library cards onto my phone the hard way

#168

Post by LeafItAlone »

monksy wrote: post #167
LeafItAlone wrote: post #69

Earlier quoted context omitted.

> as that cc s get replace far more frequently than transit cards. The only person this really benefits is new users to the system that haven't figured out how to get a transit card yet. I respectfully disagree. I’ve lost more transit cards than credit cards. And since the tap-to-pay on credit card also works with Apple Pay and Apple has the ability to choose which card to apply transit charges to, it gets the same o…

How have you lost so many transit cards? I current have 4 iterations of transit cards for the CTA. I also still have many transit cards from my visits in different countries.

> so many transit cards

Well,

1. I said I lost more transit cards than credit cards. I’ve “lost” exactly one credit card so far. And I didn’t even lose it, I left it at a restaurant and when I realized it, it was a few hours later so I just got it replaced.

2. A transit card is something you use while in motion and frequently while in a hurry. When using it multiple times per day while commuting, there is significantly more opportunities than when I use my credit card. Compared to a credit card where the transaction is slower and usually not rushed.

3. Transit cards for many cities (e.g. NYC when I lived there) are designed to be mostly disposable, so they are flimsy. Compared to a thick, rigid credit card.

I also still have dozens of transit cards from different places I’ve visited. But for my home city, I lost it a few times.

Re: Getting my library cards onto my phone the hard way

#169

Post by jldugger »

lxgr wrote: post #161
jldugger wrote: post #117

Earlier quoted context omitted.

In the era before smartphones, barcode readers were highly tuned devices that emitted a specific frequency of light and the sensor was tuned for exactly that. Cellphone screens generally don't emit that frequency of red, and I guess absorb rather than reflect light sent to it, making the screen opaque. So even if you, the human, can read it doesnt mean the device that authorizes you can.

Definitely, but what I mean is that that's not a failure mode specific to Apple passes. If a screenshot a barcode works, so should the pass, and vice versa.

Still seems like a waste of time if your MVP fails tho.

Re: Getting my library cards onto my phone the hard way

#170

Post by monksy »

LeafItAlone wrote: post #168
monksy wrote: post #167

Earlier quoted context omitted.

How have you lost so many transit cards? I current have 4 iterations of transit cards for the CTA. I also still have many transit cards from my visits in different countries.

> so many transit cards Well, 1. I said I lost more transit cards than credit cards. I’ve “lost” exactly one credit card so far. And I didn’t even lose it, I left it at a restaurant and when I realized it, it was a few hours later so I just got it replaced. 2. A transit card is something you use while in motion and frequently while in a hurry. When using it multiple times per day while commuting, there is significant…

Oh, no I'm not referring to the temporary limited used cards. I'm talking about full on plastic card backed by an account.

Oyster card, ventra card, charlie card, SUBE, etc.

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