TL-DR:
Uploading high-res JPG files to Google Maps will be stored unaltered on Google servers but only be displayed with a resolution of ~1024 pixels.
Hi, as I am curious in how Google Maps stores and displays images regarding upload and displayed quality i think i’m on to something 
I do like to upload quality images but also wondered why when viewing these images back again the quality seems less than the uploaded version and what causes this.
So I reviewed and uploaded some images and for testing purposes I specifically focused on a particular picture/image:
- Filename: 5Z1A5409-Pano.jpg
- Resolution: 2284x3000
- Size: 6,31 MB
All tests concluded on a Windows 11 computer with Microsoft Edge / Google Chrome.
Google Maps review single image share:
The uploaded photo/image can be found here:
https://maps.app.goo.gl/ycvUxP2nBRtepoQ67
Google loads the image from this URL:
https://lh3.ggpht.com/p/AF1QipNm2wWZ93oHloeL9fumrPt5GsTihM_RylFSsXu7=s1024
Image displayed resolution: 780x1024px (scaled down resolution of the original 2284x3000px)*
*Image source URL Obtained with Microsoft Edge / Chrome browser: Developer Tools | Application | Frames | Image |
Observation:
- Google Maps dynamically resizes displayed photo (long edge) to an average of 1024 pixels.
- Google Maps image URL contains parameters which corresponds with image resolution.
Further testing with above findings:
- When I modify the URL (replaced s=1024 with s=0) I get the full resolution file:
https://lh3.ggpht.com/p/AF1QipNm2wWZ93oHloeL9fumrPt5GsTihM_RylFSsXu7=s0 - When I save the file I get the original filename ‘5Z1A5409-Pano.jpg’ with almost the same original filesize.
The small difference in filesize is due to the processing of Google (removing the) metadata. The imagedata is bitwise equal.
Conclusion: - Google Maps stores the uploaded image 1/1 (only metadata stripped when displaying image)
- Google Maps resizes displayed image to 1024 pixels (long side) even when the source material contains a much higher resolution.
As I’m curious in how Google stores the uploaded file (like quality/resolution etc.) I tried to find how how to obtain the souce image in it’s fullest quality:
Methods to obtain source photo:
I could leverage 2 methods in obtaining the full resolution photo from Google Maps to establish the image quality stored on Google Servers:
- Report Problem method
- Google Takeout
‘Report problem’ method (please use carefully!!! don’t report an image by accident!!):
When ‘reporting a problem’ the image will be loaded in a separate ‘reporting’ webbrowser page and the image can be ‘right clicked’.
The options ‘save image as’ and ‘open in new tab’ are unlocked when using the context menu (right mouse button).
I choose open in a new tab and the image will be displayed in a new tab.
https://lh3.googleusercontent.com/p/AF1QipNm2wWZ93oHloeL9fumrPt5GsTihM_RylFSsXu7=s0
Resolution: 2284x3000 (original)
Observation:
- https://lh3.googleusercontent.com/p/AF1QipNm2wWZ93oHloeL9fumrPt5GsTihM_RylFSsXu7=s0
As earlier established Google resizes the photo due to the parameter =s
=s0 seems the parameter to display the image in its original resolution (here 2284x3000). - Comparing the URL’s the image is obtained from:
https://lh3.googleusercontent.com/p/AF1QipNm2wWZ93oHloeL9fumrPt5GsTihM_RylFSsXu7=s0
https://lh3.ggpht.com/p/AF1QipNm2wWZ93oHloeL9fumrPt5GsTihM_RylFSsXu7=s1024
Although the servername is different the AF1QipNm2wWZ93oHloeL9fumrPt5GsTihM_RylFSsXu7 seems to be the unique destination for this image. - If omitting the =s the resoltion seems to default to 512 pixels on the long side.
- Playing with s=
https://lh3.ggpht.com/p/AF1QipNm2wWZ93oHloeL9fumrPt5GsTihM_RylFSsXu7=s2500
1903x2500 (resized to 2500px long side)
https://lh3.ggpht.com/p/AF1QipNm2wWZ93oHloeL9fumrPt5GsTihM_RylFSsXu7=s2900
2208x2900 (resized to 2900px long side)
https://lh3.ggpht.com/p/AF1QipNm2wWZ93oHloeL9fumrPt5GsTihM_RylFSsXu7=s4600
2284x3000 (not resized/enlarged kept on the original 3000px long side)
Again this ‘proves’ that Google Maps does retain the original uploaded image but displayed with resized resolution accordingly.
Google Takeout:
Another way to obtain the Google Maps source images/photo’s.
Go to https://takeout.google.com/ and for this to work do select at least the option to takeout: ‘Maps’
When choosing and completing Google Takeout Google will queue the takeout and will notify you when you can download your data.
When the Takeout is ready you can download a zip file containing ‘your’ Google data.
Takeout\Maps\Photos Contribution
Again I can find my uploaded photo’s here in 1/1 quality so 100% the same as the uploaded source image (also the metadata might differ but the photo data itself is original)
Conclusion:
Even after a quick test of several photos I can conclude that:
-
The ‘Good’:
Google Maps keeps a 100% copy of the original uploaded file on its servers.
Uploading ~8MB high quality JPG files w/3000pixels on the long side is accepted. -
The ‘bad’:
Google Maps will unfortunately display the image in a downgraded resolution of ~1024 pixels.
Final words:
Though you can upload HQ JPG files it seems that Google Maps only displays images in a ~1024 pixel resolution (even on my 4K monitor).
But because Google Maps retains the original upload quality a future update might bump up the displayed resolution.
This concludes my search in the upload quality versus displayed quality of Google Maps.
Please add or correct my findings (just really like the technical details behing Google Maps / images)
Regards,
Arian! 