Device: Samsung Galaxy S5 /MMB29M (6.0.1)
Printer: HP Pagewide 452dW
Chrome version: 59.0.3071.125

1. Launched Chrome stable.
2. Visit http://wwww.cnn.com  web site
3. Select share from settings, printer, changed to Black and white.

Preview: Monochrome as expected.

Please upgrade to latest release from playstore and see if you can repro the issue.

Thanks

Device : Samsung Galaxy S8 (android 7.0)
Chrome version : 59.0.3071.125

still reproducible.

Thank you for providing more feedback. Adding requester "ramine@chromium.org" to the cc list and removing "Needs-Feedback" label.

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Seems to be specific to Samsung Galaxy S8/ and repro with Chrome stable '59.0.3071.125'.

Thanks for information.

Able to repro with '56.0.2924.87' chrome shipped with device.

ramine@, could you please give a screenshot of result you described in comment 2?
 If the printer is "Save as PDF", I never seen B&W preview. You are seeing B&W preview might be because you have "HP Pagewide 452dW" as printer.

Also want to confirm with heeyoun.lee@, are you using "Save as PDF" printer?

Please find logs and screen record at:

http://go/chrome-androidlogs1/7/739333

Added Files:
PrintPreview.log
printPreview.mp4

ramine@, thanks for providing log and video!

I am a bit confused, in comment 2 you mentioned "Preview: Monochrome as expected.", but in the video, it shows colored preview, so this is not specific to Samsung devices right? Also, I can reproduce this with Nexus 6P with multiple version of chrome.

This bug was specific to S8 as submitter explained and did not repro on Galaxy S5. Have not check on Nexus 6P.

ramine@, by checking the code, it is not possible that did not repro on Galaxy S5, we are not using the black and white/color parameter from Android at all, it will always show colored preview.

Also in the video you uploaded, it is still showing colored preview after change option from color to black and white.

thestig@, dgn@, by checking linux chrome, we are not showing "black and white" option when choose "Save as PDF". But on Android, "Save as PDF" printer is set to have the capability to print in both "color" and "black and white" mode by default.

So I am thinking in two ways:
1) Disable "black and white" option for "Save as PDF" printer.
2) Support "black and white" option.

For 1), by a check on Android side, I didn't see we can disable this option, I might missed it, will check it later.

For 2) color/b&w are handled by printing preview code, printing itself doesn't seem to have the option, so it evolves more fragmentation to other platforms.

thestig@, dgn@, any thoughts? Correct me if I missed something.

On Pixel running O Preview and Chrome Canary (61.0.3154.3) I don't have the option to switch to black and white. Nexus 5 on L and M still shows the option. So maybe the OS finally starts respecting Chrome's B&W preference from O? In that case I don't think we want to add B&W support for PDF on Android.

dgn@, forgot to mention that we don't have B&W option for "Save to Google Drive" but we do have that for "Save as PDF", you might want to make sure the printer is "Save as PDF".

Oh you're right. Anyway, that means there should be a way to specify this for the framework. 

There is this class: https://developer.android.com/reference/android/print/PrinterCapabilitiesInfo.Builder.html

We don't seem to use it anywhere.

It seems there is no way to control capabilities of printer. 

PrinterCapabilitiesInfo is used for a printer to tell Android framework its capabilities, it is initialized for a printer and won't be changed later.

Most likely we have no way to control UI, if we want to respect this kind of options, we need to generate black & white PDF file IMO.

dgn@, thestig@, any thoughts?

Sounds good, I didn't realise B&W preview doesn't work at all even on regular printers. We should support it at some point, yes.

Maybe halcanary@ has an opinion re: comment 17. I recently ran into a similar problem with Windows printing. I solved that in r550078, where the color PDF is being rendered to grayscale later in Windows-specific code.

Thanks Lei for the info!

Changwan, another printing related task for WebView/Chrome for Android to consider.

Yup, sounds like an important use case that needs fixing. ctzsm@, could you try to set the milestone for this task? Thanks.