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Is there a free service, with an API, that performs lossless image file size reduction?

Currently we use Smush.it which isn't perfect (have to resort to command line tools), although its FAQ does suggest that an API is coming (no progress on this in over 2 years).


Turns out the Smush.it API is alive and well, just advertised as dead. Sending requests to: http://www.smushit.com/ysmush.it/ws.php?img=VALID_IMAGE_URL (where VALID_IMAGE_URL is, you guessed it, a valid URL of an image) returns a JSON object with a Smush.it address where you can download the newly created image. The JSON object also gives you statistics on the compression available.

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Great that the smush.it API is working. The PunyPNG comparison of compression results is worth considering, because smush.it doesn't quite perform as well the competition. Hard to complain when it's free, though. – Nick Aug 15 '11 at 16:13
Now using Smush.it to reduce files below 150kb (if possible) then PunyPNGing them. – Metalshark Aug 17 '11 at 8:01
up vote 4 down vote accepted

There's the PunyPNG API, which supports PNG, jpeg, and gif images.

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The images are around 200-300kb. The API limits it to 150kb or requires payment. As this is for occasional use the pricing scheme isn't ideal. – Metalshark Aug 15 '11 at 14:04
@Metalshark Are you sure it's 150kb? It says the maximum is 500kb on the API page: bit.ly/podL5B I spent a while looking and that was the only other image compression service with an API that I could find, I'm afraid. Image compression via API is a niche service because it's not too hard to do it on your own server using e.g. OptiPNG. – Nick Aug 15 '11 at 14:28
its only 150kb for the free version (500kb costs $5 per month). Wasn't aware of PunyPNG, so thank you for bringing it to attention. Using Google App Engine so local executables are a no-no. – Metalshark Aug 15 '11 at 15:24

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