javascript - HTML5 Canvas created JPEG is "corrupt" or "damaged"? -


i have simple html5 canvas object that, once saved file, opens perfeclty in photoshop , looks correct, according windows , osx "corrupted" or "damaged".

the code i'm using simple:

javascript:

var dataurl = canvas.todataurl({     format: 'jpeg',     quality: 0.8 });

and sending dataurl via ajax:

      $.ajax({          type: "post",          url: "scripts/saveimage.php",          data: {             imgbase64: dataurl          }       })

to simple php script:

$imagebase64 = $_post['imgbase64']; $imagedata = base64_decode($imagebase64); file_put_contents($filename,$imagedata);

the file created file. can open in photoshop , looks expected. hex editor shows has jfif in headers, you'd expect jpeg, too:

enter image description here

but can't open file in windows or osx preview:

enter image description here

have done wrong? there in file header that's throwing off windows/osx? or expected behavior jpeg created in way?

i had same problem, turned out "dataurl" started data:image/png;base64, confusing reader programs such windows media viewer etc.

to solve problem used code

$file = base64_decode(str_replace(' ', '+', str_replace('data:image/png;base64,', '', \input::data('base64image'))));

i guess have change to

$file = base64_decode(str_replace(' ', '+', str_replace('data:image/jpeg;base64,', '', $_post['imgbase64'])));

honestly, don't remember purpose of first str_replace , reason i've included in answer, because may break if removed it.


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