It's Cree, probably an eastern variety judging by the presence of the š-series. The last three words are "kici-peci takošina".

Thanks! What about the final letter? It doesn't seem to be part of the Eastern Cree orthography. And what about the first word, which begins with a final letter?

Oh right, my bad: takošinan.

Hmm, now I'm not sure, since that's a Western Cree convention. (I misread it as going the other way, which is the Eastern Cree convention for final /t/.) Maybe there's some variety of Cree that mixes and matches from the two orthographies?

The first word would be nkiskentetan. I'm not sure if this is Cree or Ojibwe. There is a š/s distinction in North Ontario, James Bay and southwestern Quebec Cree (where they merge to /s/ further west and to /s/, /š/ or /h/ further east).

If it's Ojibwe, the double curl syllabogram would be /ž/, spelled 'zh' in most Ojibwe/Algonkin/Odawa Latin script orthographies.

This comes from an installation by the Toronto photographer Howard Chan on the outside of the Metro Toronto Convention Centre on Front Street, across from the CBC Broadcast Centre, right?

it's western cree

When I put up the picture on a Facebook Cree language group, someone said the ‹ši› syllabogram (the ʃ-like shape) was "not Cree". It was confusing to people because the contrast between /ʃ/ and /s/ exists only in the Cree dialects southwest of James Bay in North Ontario (Swampy Cree) and southern Quebec. To the east, the two sounds merge into a single phoneme, /s/, /ʃ/ or /h/, depending on dialect (with positional allophony in the Montagnais/Innu/Ilnu dialects of eastern Quebec and Labrador), and to /s/ in northwestern Ontario and all dialects further west.

So since it has this contrastive /ʃ/ phoneme, it can't be western Cree.

Correct. and thanks for your help!