How does Shazam work? • Hacker News Board

Re: How does Shazam work?

#21

Post by [deleted] » Thu, Apr 23, 2026, 4:51 AM UTC

BLKNSLVR wrote: post #5

gnabgib wrote: post #3

Again? Oh I see.. SCP (this domain is sus) From CameronMacLeod (2022) - and much more complete analysis (587 points, 2023, 155 comments) https://news.ycombinator.com/item?id=38531428 Or Slate (2009) (50 points, 16 comments) https://news.ycombinator.com/item?id=893353

Forgive my ignorance, but what does SCP mean in this context? (my normal go-to of 'secure copy' doesn't fit). Thanks for the other links, the question in this title is one I've day-dreamily thought about on occasion, but never dug into. Will have a read of all three.

[deleted]

Re: How does Shazam work?

#22

Post by flyuk » Thu, Apr 23, 2026, 4:55 AM UTC

Nice article - enjoyed reading!

Re: How does Shazam work?

#23

Post by thakoppno » Thu, Apr 23, 2026, 5:07 AM UTC

krustyburger wrote: post #18

thakoppno wrote: post #14

Perhaps obviously this is the same technique that enables ACR on TVs. It occurs to me that Shazam has such a better reputation online because the intent and consent of the user is honored. It makes me wonder if there couldn’t be an implementation on TVs that is similar and actually is a net positive for consumers. Basically would customers actually like TV ACR if the data wasn’t just going to sell more ads?

So the value-add would be the consumer would get to find out the name of the show or movie that’s playing, the same info that also pops up if they hit the pause button?

I was thinking more like interactive content. Do you remember when VH1 had a pop-up music video show?

Shows could synchronize additional content that’d be visible when Shazam mode enabled.

Re: How does Shazam work?

#24

Post by eichin » Thu, Apr 23, 2026, 5:08 AM UTC

BLKNSLVR wrote: post #5

gnabgib wrote: post #3

Again? Oh I see.. SCP (this domain is sus) From CameronMacLeod (2022) - and much more complete analysis (587 points, 2023, 155 comments) https://news.ycombinator.com/item?id=38531428 Or Slate (2009) (50 points, 16 comments) https://news.ycombinator.com/item?id=893353

Forgive my ignorance, but what does SCP mean in this context? (my normal go-to of 'secure copy' doesn't fit). Thanks for the other links, the question in this title is one I've day-dreamily thought about on occasion, but never dug into. Will have a read of all three.

probably the HN-specific "Second Chance Pool" for resurfacing links

Re: How does Shazam work?

#25

Post by w-ll » Thu, Apr 23, 2026, 5:18 AM UTC

thakoppno wrote: post #23

krustyburger wrote: post #18

Earlier quoted context omitted.

So the value-add would be the consumer would get to find out the name of the show or movie that’s playing, the same info that also pops up if they hit the pause button?

I was thinking more like interactive content. Do you remember when VH1 had a pop-up music video show? Shows could synchronize additional content that’d be visible when Shazam mode enabled.

Pop. Pop. Pop Up Video.

Re: How does Shazam work?

#26

Post by larodi » Thu, Apr 23, 2026, 5:26 AM UTC

There's an algo called dynamic time warping (DTW) and is very often overlooked. My wild guess would be is at play @Shazam.

Re: How does Shazam work?

#27

Post by flymasterv » Thu, Apr 23, 2026, 5:29 AM UTC

thakoppno wrote: post #23

krustyburger wrote: post #18

Earlier quoted context omitted.

So the value-add would be the consumer would get to find out the name of the show or movie that’s playing, the same info that also pops up if they hit the pause button?

I was thinking more like interactive content. Do you remember when VH1 had a pop-up music video show? Shows could synchronize additional content that’d be visible when Shazam mode enabled.

We did this on Fire Phone for live sports and audio based X-Ray cast info. It was, like everything about that phone, a really fun tech demo.

Re: How does Shazam work?

#28

Post by old_bayes » Thu, Apr 23, 2026, 5:29 AM UTC

larodi wrote: post #26

There's an algo called dynamic time warping (DTW) and is very often overlooked. My wild guess would be is at play @Shazam.

Ayyy I used DTW to track bots on a certain social media site. They tend to act in herds so DTW helps smooth out delayed, repeat actions.

Re: How does Shazam work?

#29

Post by knodi123 » Thu, Apr 23, 2026, 5:32 AM UTC

G_o_D wrote: post #17

Out of curiosity is it possible to prevent shazam like app from detecting maybe by adding noise or any technique ?

Not unless your noise is louder at certain dominant frequencies than the source. The article gives examples, but the algorithm basically throws away everything except frequency peaks, in order to make the lookups faster.

Re: How does Shazam work?

#30

Post by Gigachad » Thu, Apr 23, 2026, 5:51 AM UTC

Animats wrote: post #8

Recognizing a recording isn't hard to do, because, for the same recording, the chords follow each other with precisely repeatable timing. That's been around for well over a decade. Recognizing a different recording, say, a, cover version, of the same song, is much more work. Audible Magic claims to be able to recognize multiple performances of the same songs, and even parodies.[1] Using, of course, "AI technology" an…

"Isn't hard to do" is doing some heavy lifting. Obviously on a society level it's simple tech we managed ages ago. But I would bet if you tasked individual devs at building it without looking up the answer, very few could do it.