Brightness setting unaffective when scanning with MFP M177fw

[Zoltan Peller]

The scan results from almost all the scan programs (simple-scan, scanimage, hp-scan) are way too light, faded, and missing details when scanning with my MFP M177fw from Linux (Debian 7.8 x86), so I've tried to adjust brightness and contrast settings from the command line, like this:

hp-scan -b -500 -c -10 or this:
scanimage -d hpaio:/net/HP_Color_LaserJet_Pro_MFP_M177fw?ip=10.1.1.23 --mode Gray --resolution 300 --contrast 20 --brightness 500 -vvvvv

Tried scanning in different modes (Gray and Color) and resolutions (150/300/600), and also compression modes. In color mode neither the contrast, nor the brightness settings had any effect (tried -1000, -500, 0, 500, 1000 and even far out of range). In gray mode the contrast worked, but not the brightness. With turning SANE and other debug switches on, it looks like the command is sent to SANE (even looks accepted), but it has no effect (see logs below).

This might be a problem with the scanner or with the driver, I can't tell. This is my third HP MFP printer, and never had similar problems with hplip scanning.

The output from hp-check is attached (latest hplip as of today, also latest available firmware for printer/scanner), and I can send sample images if necessary. (Showing the lack of difference)

The output from hp-scan:

HP Linux Imaging and Printing System (ver. 3.15.2)
Scan Utility ver. 2.2

Copyright (c) 2001-15 Hewlett-Packard Development Company, LP
This software comes with ABSOLUTELY NO WARRANTY.
This is free software, and you are welcome to distribute it
under certain conditions. See COPYING file for more details.

hp-scan[26965]: debug: getDeviceUri(None, None, ['hpaio'], {'scan-type': (<built-in function gt>, 0)}, , True)
hp-scan[26965]: debug: Mode=0
hp-scan[26965]: debug: Cache miss: hp_color_laserjet_pro_mfp_m177fw
hp-scan[26965]: debug: Reading file: /usr/share/hplip/data/models/models.dat
hp-scan[26965]: debug: Searching for section [hp_color_laserjet_pro_mfp_m177fw] in file /usr/share/hplip/data/models/models.dat
hp-scan[26965]: debug: Found section [hp_color_laserjet_pro_mfp_m177fw] in file /usr/share/hplip/data/models/models.dat
hp-scan[26965]: debug: {'hpaio:/net/HP_Color_LaserJet_Pro_MFP_M177fw?ip=10.1.1.23': ['lucky', 'lucky-color']}
Using device: hpaio:/net/HP_Color_LaserJet_Pro_MFP_M177fw?ip=10.1.1.23

warning: No destinations specified. Adding 'file' destination by default.
Using device hpaio:/net/HP_Color_LaserJet_Pro_MFP_M177fw?ip=10.1.1.23
Opening connection to device...
hp-scan[26965]: debug: Supported source Options: ['Flatbed', 'ADF'] size=2
hp-scan[26965]: debug: Device supported resolutions [75, 100, 150, 200, 300, 600, 1200]

Resolution: 300dpi
Mode: gray
Compression: JPEG
Contrast: 10
Brightness: -1000
Scan area (mm):
  Top left (x,y): (0.000000mm, 0.000000mm)
  Bottom right (x,y): (215.899994mm, 296.925995mm)
  Width: 215.899994mm
  Height: 296.925995mm
Destination(s): file
Output file:
hp-scan[26965]: debug: Supported modes: ['lineart', 'gray', 'color'] size=3
warning: File destination enabled with no output file specified.
Setting output format to PNG for greyscale mode.
warning: Defaulting to '/fhome/zpeller/hpscan010.png'.

Warming up...

Scanning...
hp-scan[26965]: debug: expected_bytes = 8936794
hp-scan[26965]: debug: format=0
hp-scan[26965]: debug: Expecting to read 8.5 MB from scanner.
hp-scan[26965]: debug: format_name=gray
hp-scan[26965]: debug: last_frame=1
hp-scan[26965]: debug: ppl=2549
hp-scan[26965]: debug: lines=3506
hp-scan[26965]: debug: depth=8
hp-scan[26965]: debug: bpl=2549
hp-scan[26965]: debug: byte_format=RGBA
hp-scan[26965]: debug: pad_bytes=0
hp-scan[26965]: debug: Gray Read 2549 bytes
hp-scan[26965]: debug: Gray Read 5098 bytes
...
hp-scan[26965]: debug: Gray Read 8934245 bytes
hp-scan[26965]: debug: Gray Read 8936794 bytes
hp-scan[26965]: debug: Scan thread exiting...

Read 8.5 MB from scanner.
hp-scan[26965]: debug: PPL=2549 lines=3506 depth=8 BPL=2549 pad=0 total_read=8936794 total_write=35747176
Closing device.

Outputting to destination 'file':
Saving to file /fhome/zpeller/hpscan010.png

Done.

[goutam (goutamkk)]

Hi Zoltan,

Thank you for reporting this issue. We will try and reproduce the same here.
Can you confirm the same behavior on xsane application ?

Rgds,
goutam

[Zoltan Peller (zpeller)]

Hi goutam,

I can confirm the exact the same behaviour in xsane if I try to adjust contrast and brightness on the "Advanced options" panel. Brightness never works, contrast works only in grayscale mode, not in color mode.

(The brightness and contrast options on the main panel work of course, as they do post processing. In auto correction mode the gamma value almost always jumps to 0.83-0.85, which confirms that the image coming from the scanner is too bright.)

Regards,
Zoltan

[Carl (n6rl)]

Affects me as well. Printer/scanner is the same, MFP M177fw, I'm running Ubuntu 14.04 64-bit.

$ hp-scan
HP Linux Imaging and Printing System (ver. 3.14.3)
Scan Utility ver. 2.2

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[gf (gf-interlinks-deactivatedaccount)]

Hello Zoltan,
Thank you for submitting this bug and reporting a problem with hplip. You made this bug report some time ago and Ubuntu and hplip have been updated since then.

Could you confirm that this is no longer a problem and that we can close the ticket?
If it is still a problem, are you still interested in finding a solution to this bug?
If you are, could you let us know and, in the current version, could you run the following (only once):
apport-collect 1424451
and upload the updated logs and and any other logs that are relevant for this particular issue.

Thank you again for helping make Ubuntu and hplip better.
G
[Ubuntu Bug Squad volunteer triager]

[Zoltan Peller (zpeller)]

Hello,

Currently I'm using Debian 9.5 and hplip 3.6.11. And although I've done only a light check from simple-scan (tried different brightness settings in gray mode), the behaviour looks the same, no difference in the output, so the bug still exists.

But as I don't use the scanner too often, and not for professional purposes, it's ok for me, if the bug is left unfixed. I use a small script to apply a -0.3 gamma correction on the images after scanning, and that gives me just good enough result for my purposes. xsane's auto gamma correction also works fine.

Regards,
Zoltan

[gf (gf-interlinks-deactivatedaccount)]

Hi Zoltan. Thanks for the update. I will check with the bug team see if they want to pursue this.
Take care
:)
G

[gf (gf-interlinks-deactivatedaccount)]

Hi Zoltan, we will leave this bug report at "incomplete" status in case someone else might have the same problem in the next little while. If not, it will be expired automatically.
Take care and thanks again for taking the time to report.
:)
G

[Launchpad Janitor (janitor)]

[Expired for hplip (Ubuntu) because there has been no activity for 60 days.]

[Markus B (broedem)]

I have a HP Laserjet M1522nf and working with Kubuntu 18.04.2 I have exactly the same problems.
A few days before I used a Tuxedo Linux and scanning was perfect.
The problems began after using the original Kubuntu distribution.