Review Request 113397: RAW preview in gwenview

[Aurélien Gâteau]

>
>
>> On Nov. 5, 2013, 5:04 p.m., Aurélien Gâteau wrote:
>> > lib/thumbnailprovider/thumbnailgenerator.cpp, line 128
>> > <http://git.reviewboard.kde.org/r/113397/diff/6/?file=206503#file206503line128>
>> >
>> >     It looks to me like the new code is never going to use the
>> embedded thumbnail, this could have a bad impact on performance.
>
> Yep, it seems so. However, using the embedded small thumbnail has some
> serious drawbacks:
>
> 1) there's no particular function in libraw (nor kdcraw), fetching the
>    small size thumbnail (unpack_thumb() returns the large preview if
>    present)
> 2) not every raw file contains the small thumb
> 3) the thumbnail (if any) is always 160x120 (4:3) while majority of
>    the raw-enabled cameras shoot 3:2 pictures. That leads to ugly
>    black stripes along the longer sides of the thumbnail.
> 4) the thumbnail view shows the 160x120 as a resolution of the image
>    (not sure if this can be overriden by exif data and how)

I was not speaking about raw files here. I am concerned about jpeg
files. Embedded thumbnails are useful for jpeg files, Gwenview must use
them if they are available.

Aurélien