5 ms·

Remove personal data from photos before sharing them on the internet

6 points by ndesaulniers 12y ago

xiaomai 12y ago
This is great, I always remove the metadata from files before sharing them (why don't the social networks don't do this for you?). This is how I do it at the command-line: cp files-to-strip /tmp/foo exiv2 rm /tmp/foo/*
- sagarjauhari 12y ago
  Why would the social networks ever do that for you? That's the data they crave for.
- billmalarky 12y ago
  If I recall correctly in a old reddit ama Alan Schaaf said that Imgur strips all metadata from images on upload.
pdkl95 12y ago
There might be value in having an image[2] [container?] file format that is explicitly incompatible with EXIF and other metadata. This includes not having any kind of "comment" field or free-form data such as JPEG's "APP1" location where the EXIF data is stored. It would specify only height, width, ppi, gamma, and some enumerated bitfields to identify the pixel format and any necessary compression options (i.e. lossy/DCT vs DEFLATE). Even better, it should have some sort of self-checksum of the entire file, so it is harder (but not impossible, unfortunately) to extend the format beyond the original spec. This would make it far simpler to encourage better behavior: the average person isn't going to bother if you tell them to run exiv/exiftool. Instead, saying "Normal image files are not safe! Only upload $SAFE_FORMAT files!" will get at least some people to strip the files, and those that don't should at least get a more useful sense of what is safe/risky. In the (very hypothetical) future, once the format was used, it would even be possible to for browsers to explicitly deny upload of JPEG/PNG/etc or they could auto-convert other formats. Security doesn't work when it relies on complicated methods that won't actually be use in practice, so changing the format of stuff that is used might be necessary. [1] the same idea would obviously apply to audio/video/whatever files

5 ms·

Remove personal data from photos before sharing them on the internet

6 points by ndesaulniers 12y ago

xiaomai 12y ago
This is great, I always remove the metadata from files before sharing them (why don't the social networks don't do this for you?). This is how I do it at the command-line: cp files-to-strip /tmp/foo exiv2 rm /tmp/foo/*
- sagarjauhari 12y ago
  Why would the social networks ever do that for you? That's the data they crave for.
- billmalarky 12y ago
  If I recall correctly in a old reddit ama Alan Schaaf said that Imgur strips all metadata from images on upload.
pdkl95 12y ago
There might be value in having an image[2] [container?] file format that is explicitly incompatible with EXIF and other metadata. This includes not having any kind of "comment" field or free-form data such as JPEG's "APP1" location where the EXIF data is stored. It would specify only height, width, ppi, gamma, and some enumerated bitfields to identify the pixel format and any necessary compression options (i.e. lossy/DCT vs DEFLATE). Even better, it should have some sort of self-checksum of the entire file, so it is harder (but not impossible, unfortunately) to extend the format beyond the original spec. This would make it far simpler to encourage better behavior: the average person isn't going to bother if you tell them to run exiv/exiftool. Instead, saying "Normal image files are not safe! Only upload $SAFE_FORMAT files!" will get at least some people to strip the files, and those that don't should at least get a more useful sense of what is safe/risky. In the (very hypothetical) future, once the format was used, it would even be possible to for browsers to explicitly deny upload of JPEG/PNG/etc or they could auto-convert other formats. Security doesn't work when it relies on complicated methods that won't actually be use in practice, so changing the format of stuff that is used might be necessary. [1] the same idea would obviously apply to audio/video/whatever files