assetDirs option corrupts images

[RafaelVidaurre]

For some reason when specifying the assetDIrs option, the task corrupts every image it finds. Am I doing something wrong?

Why is this task writing into the files, I though the purpose of assetDirs was to replace references of revved files into css/js

Processing as ASSETSDIRS - dist/images/prensa-1.06b2d701.jpg
Writing dist/images/prensa-1.06b2d701.jpg...OK
Processing as ASSETSDIRS - dist/images/prensa-2.86ddc902.jpg
Writing dist/images/prensa-2.86ddc902.jpg...OK
Processing as ASSETSDIRS - dist/images/prensa-3.bc988a6e.jpg
Writing dist/images/prensa-3.bc988a6e.jpg...OK
Processing as ASSETSDIRS - dist/images/prensa-4.4c26babf.jpg
Writing dist/images/prensa-4.4c26babf.jpg...OK
Processing as ASSETSDIRS - dist/images/prensa-5.38d96246.jpg
Writing dist/images/prensa-5.38d96246.jpg...OK
Processing as ASSETSDIRS - dist/images/prensa-6.929b8a64.jpg
Writing dist/images/prensa-6.929b8a64.jpg...OK
Processing as ASSETSDIRS - dist/images/prensa-p1.36bc1229.png
Writing dist/images/prensa-p1.36bc1229.png...OK
Processing as ASSETSDIRS - dist/images/prensa-p2.b35aefc6.png
Writing dist/images/prensa-p2.b35aefc6.png...OK
Processing as ASSETSDIRS - dist/images/prensa.d41fc97e.png
Writing dist/images/prensa.d41fc97e.png...OK
Processing as ASSETSDIRS - dist/images/raya.65590da0.png
Writing dist/images/raya.65590da0.png...OK
Processing as ASSETSDIRS - dist/images/testimonio-facebook.1fe6c6f9.png
Writing dist/images/testimonio-facebook.1fe6c6f9.png...OK
Processing as ASSETSDIRS - dist/images/testimonio-facebook2.87796840.png
Writing dist/images/testimonio-facebook2.87796840.png...OK
Processing as ASSETSDIRS - dist/images/testimonio-twitter.8ad96c14.png
Writing dist/images/testimonio-twitter.8ad96c14.png...OK
Processing as ASSETSDIRS - dist/images/testimonio-twitter2.aa1fa838.png
Writing dist/images/testimonio-twitter2.aa1fa838.png...OK
Processing as ASSETSDIRS - dist/images/toggle-1.e3091600.png
Writing dist/images/toggle-1.e3091600.png...OK
Processing as ASSETSDIRS - dist/images/toggle-2.7ef8d6f3.png
Writing dist/images/toggle-2.7ef8d6f3.png...OK
Processing as ASSETSDIRS - dist/images/toggle-3.89db3537.png
Writing dist/images/toggle-3.89db3537.png...OK
Processing as ASSETSDIRS - dist/images/trust-logos.ec308c70.png
Writing dist/images/trust-logos.ec308c70.png...OK
Processing as ASSETSDIRS - dist/images/video.90010b84.png
Writing dist/images/video.90010b84.png...OK
Replaced 62 references to assets

Note that I tried assetDirs as a task alone with the same results.