[magick-users] Re: Trouble converting 300dpi jpeg to 72dpi jpeg with same size

[Nicolas Dhomont]

Thanks for your answer Michal.

I tried :

convert -units PixelsPerInch fromFile -density 72x72 toFile

But 'toFile' is still in 300dpi. 'toFile' file size is even more bigger 
than 'fromFile' file size. lol

Nicolas

Michał Skalski a écrit :
> Try -density option instead of -resample
>
> Michał
>
> Nicolas Dhomont pisze:
>> Hello
>>
>>
>> I'm trying to convert 300dpi CYMK jpeg to 72dpi RGB jpeg
>>
>> I already manage to convert from CYMK to RGB by doing the following :
>>
>> convert fromFile -antialias -colorspace RGB toFile
>>
>> I'm now trying to convert from 300 dpi to 72dpi with the following :
>>
>> convert -units PixelsPerInch fromFile -colorspace RGB -antialias 
>> -resample 72x72 toFile
>>
>> Size of toFile is reduced by a 4,16 ratio (= 300 / 72) but still in 
>> 300 dpi. (It means that if fromFile is 2.66inch wide, toFile is 
>> 2.08inch wide for exemple). But I want exactly the opposite : a file 
>> in 72 dpi with same size.
>> I've also played with the -density option unsuccessfully.
>>
>> As converting is quite simple with photoshop, I guess convert can do 
>> same but I can't find out how.
>>
>>
>>
>> Any help would be highly appreciated
>>
>> Nicolas