samvermette samvermette - 3 years ago 165
Ruby Question

JPG to PNG using RMagick

I'm trying to convert a fetched image from JPG to PNG using RMagick, resize it and then store it on S3:

thumb = Magick::Image.read("artist.jpg").first
thumb.write("artist.png")
thumb.crop_resized!(120, 120, Magick::CenterGravity)

AWS::S3::S3Object.store("image.png", thumb.to_blob, AWS_BUCKET, :content_type => 'image/png', :access => :public_read)


The image does get saved as a png but when I open it in Preview, document type still says "JPEG image". In fact, the image won't even open in Photoshop unless I change the extension back to ".jpg". Am I missing something?

Answer Source

Try explicitly setting the format:

thumb = Magick::Image.read("artist.jpg").first
thumb.format = "PNG"
thumb.write("artist.png")
thumb.crop_resized!(120, 120, Magick::CenterGravity)

AWS::S3::S3Object.store("image.png", thumb.to_blob, AWS_BUCKET, :content_type => 'image/png', :access => :public_read)
Recommended from our users: Dynamic Network Monitoring from WhatsUp Gold from IPSwitch. Free Download