librmagick-ruby returning incorrect image formats

[roja]

Binary package hint: librmagick-ruby

based on "librmagick-ruby_2.5.1-1_all.deb"

following results seen on ubuntu:

$ irb

irb(main):001:0> require 'rubygems'
=> true
irb(main):002:0> require 'RMagick'
=> true
irb(main):003:0> m = Magick::Image::read("http://wdfw.wa.gov/wlm/living/graphics/bat.jpg")
=> [http://wdfw.wa.gov/wlm/living/graphics/bat.jpg=>/tmp/magick-XXqepdEr HTTP 850x815 850x815+0+0 DirectClass 8-bit 100kb]

should see:

$ irb

irb(main):001:0> require 'rubygems'
=> true
irb(main):002:0> require 'RMagick'
=> true
irb(main):003:0> m = Magick::Image::read("http://wdfw.wa.gov/wlm/living/graphics/bat.jpg")
=> [http://wdfw.wa.gov/wlm/living/graphics/bat.jpg=>/tmp/magick-XX5jx7sy JPEG 850x815 850x815+0+0 DirectClass 8-bit 100kb]

as can be seen the format reported in the first example is "HTTP" not "JPEG" as it should be... This is a major issue if image format identification is required by an application.

[Bryan McLellan (btm)]

I've posted on the Imagemagick upstream bug forum [1] asking if this is intended, but I found in the changelog "Return the actual image format for HTTP: or FTP: format" [2]

This is actually an imagemagick bug, not a ruby one:

$ /usr/bin/identify http://wdfw.wa.gov/wlm/living/graphics/bat.jpg
http://wdfw.wa.gov/wlm/living/graphics/bat.jpg=>/tmp/magick-XXXsBrtg HTTP 850x815 850x815+0+0 DirectClass 8-bit 100.77kb

[1] http://www.imagemagick.org/discourse-server/viewtopic.php?f=3&t=13203
[2] http://www.imagemagick.org/discourse-server/viewtopic.php?f=1&t=10715

[Bryan McLellan (btm)]

This is fixed upstream and imagemagick=7:6.4.5.4.dfsg1-1ubuntu3 in jaunty includes the fixes.

$ /usr/bin/identify http://wdfw.wa.gov/wlm/living/graphics/bat.jpg
http://wdfw.wa.gov/wlm/living/graphics/bat.jpg=>/tmp/magick-XXczwGMv JPEG 850x815 850x815+0+0 8-bit