[Scribus] File size using photos

[Gregory Pittman]

Craig Ringer wrote:
> Henry Hartley wrote:
>   
>> Nigel Ridley wrote:
>>     
>>>> This is really a newbie question but I would really like to know:
>>>> Does Scribus only use the part of a photo/graphic that is viewable
>>>> in the graphic frame or does the whole photo/graphic get put into
>>>> the end file size regardless of how much has been cropped out.
>>>> Is that clear? If not - let's say I have a 2.5Mb .jpg that I put
>>>> into a Scribus document. I then crop the .jpg as I only want a
>>>> section of the photo in the finished document - is there still
>>>> 2.5Mb of .jpg in the document?
>>>>
>>>> The reason I'm asking is that I want to make a small booklet
>>>> available on my website for download but obviously want to keep
>>>> the file size down to something reasonable (there will probably
>>>> be several graphics in the finished document).
>>>>         
>> It appears that the final PDF will have the entire image in it.
>>     
>
> That is correct, at least when resampling is off. I'm not sure if
> Scribus crops the image if resampling is on or not.
>
> There are several reasons for this behaviour:
>
> 	- If we include the whole image, and it's a JPEG source,
> 	  we don't have to re-compress it. This is a quality and
> 	  (for small crops) often size saving.
>
> 	- The image can be included in the file just once, and
> 	  differerent parts referenced from different places in
> 	  the file. You might use the left side on one side of
> 	  the page, and the right on another. You might use
> 	  part of the image as an inset in one place, and the
> 	  full size one later, etc. This can be supported without
> 	  making the file bigger by including the whole image in
> 	  the first place.
>
> Scribus would probably benefit from some heuristics for image slicing -
> when we should `cut up' the image and embed only the bits that're use,
> and when the whole image is best embedded. Factors such as source image
> type (we should be more reluctant to chop up images we can otherwise
> embed without modification) and percentage image used would need to be
> considered. However, I don't personally see this as a particularly
> urgent feature.
>   
If I understand this then, if one wanted to reduce file size, would
cropping the image outside of Scribus make the PDF smaller?

Greg