PNG driver doesn't support 5 bands

[MarcYin]

Problem description

[this should explain why the current behavior is a problem and why the expected output is a better solution.]

When using the titiler to render remote COGs as tile layer. One works and One does not.

A xyz tile for the working one

A xyz tile not working one

Expected Output

Both of them should work...

Environment Information

Javascript and python

[vincentsarago]

The error message is quite meaningful, you're trying to create a PNG tile with 5 bands (4 data bands and 1 alpha band)

Looking at your file:
https://titiler.xyz/cog/info?url=https://gws-access.jasmin.ac.uk/public/nceo_isp/S2/30/V/VH/S2B_MSIL1C_20210112T113339_N0209_R080_T30VVH_20210112T123741.SAFE/GRANULE/L1C_T30VVH_A020126_20210112T113447/IMG_DATA/BOA_RGB.tif

It's a 4 bands data (none of the band tagged as alpha or mask) so when creating a tile you need to pass band indexes (bidx=1&bidx=2&bidx=3)

[MarcYin]

Thanks for the reply. Would it be possible to automatiaclly identify the fourth band as the alpha channel?