Glue chunks to jpeg file

[asantos]

Hi, im developing an API for a java application. That java application only uploads 60kb max to the server, so if a picture is 100 kb, it uploads 60kb and the the other 40kb.

chunk.1.tmp (60kb)
chunk.2.tmp (40kb)

How can i glue them back together as a JPEG file in PHP?

I guess i should first glue them to a final.tmp file and then use imageCreateFromJPEG('final.tmp')... so as you can see, i only need help with the glue part.

Thanks!

[asantos]

It seems i already got it:

file_put_contents('chunk.tmp',file_get_contents($chunk,FILE_BINARY),FILE_APPEND);

Any ideas?

[jatar_k]

>> Any ideas?

did it work?

[asantos]

actually it did work. i meant... any ideas on how to improve that hehe.

[jatar_k]

not really, I think that's fine

especially if it works ;)

[asantos]

me again... it worked theorically... because it did glue the chunks together. Now im trying to port them to a jpeg file with:

$img = imageCreateFromJPEG($dir.'chunk.tmp');

the $img object doesnt seem to be a valid image... and the chunk.tmp weights around 20kb more than the original sliced up image that was uploaded from the java app.

Any ideas :S ?

[edited by: asantos at 4:12 pm (utc) on June 11, 2009]

[asantos]

BTW, this is my code:

$dir = 'somedir/'; 
$file = $dir.'chunk.'.$_GET['i'].'.tmp'; 
if(move_uploaded_file($_FILES['chunk']['tmp_name'],$file)) { 
# First file 
if($_GET['i']==1) { 
# Create main chunk file 
file_put_contents($dir.'chunk.tmp',file_get_contents($file,FILE_BINARY),FILE_BINARY); 
} else { 
# Append chunk! 
file_put_contents($dir.'chunk.tmp',file_get_contents($file,FILE_BINARY),FILE_APPEND); 
} 
# Last file 
if($_GET['i']==$_GET['n']) { 
# Build JPEG 
$img = imageCreateFromJPEG($dir.'chunk.tmp'); 
} 
} else { 
die('error'); 
} 

[jatar_k]

no clue actually

I would guess at the java is changing/appending/terminating the chunks

possibly even adding in extra data in the beginning of the file

I would say you need to figure out what exactly the java is doing to the data before you can reassemble it

[asantos]

found the error ;)
it seems the java code was resending the last byte of the chunk in the next chunk.

the code i posted works perfectly. i hope someone can use it too.

[jatar_k]

nice catch