Use of PNGFiles instead of ImageMagick

[kimikage]

I think ImageShow.jl only use the PNG generation function of ImageMagick, so ImageMagick can be replaced by the new package PNGFIles.

Perhaps when we use ImageShow without image files other than PNG, PNGFiles is better. However, in many cases, other packages in use depend on ImageMagick, so it is not always better.

[johnnychen94]

Good idea, but I think that requires PNGFiles to support savestreaming method to suit

ImageShow.jl/src/showmime.jl

Line 45 in 026ccda

FileIO.save(FileIO.Stream(format"PNG", io), img)

Once that's done, ImageMagick will be automatically replaced by PNGFiles if the user has it installed.

cc: @ianshmean

[kimikage]

Well, I assumed the usage without the FileIO and streaming. In any case, we need to extend PNGFiles.

[johnnychen94]

With JuliaIO/PNGFiles.jl#14 merged, I think this is good to close; FileIO would use ImageIO if available.

[IanButterworth]

PNGFiles does indeed support streams now, and I’ll be adding support in ImageIO once PNGfiles releases. Should all be released today

[IanButterworth]

Released as of ImageIO 0.2.0 👍