image_to_j2k not outputting to win32 console properly

[gcode-importer]

Originally reported on Google Code with ID 18

What steps will reproduce the problem?
1. Attempt to redirect console output to a GUI
2.
3.

What is the expected output? What do you see instead?
Expected: See image_to_j2k output in my app
Instead: Nothing until it has completed

What version of the product are you using? On what operating system?
v1.3 image_to_j2k on Win XP SP3

Please provide any additional information below.
After reading, apparently this behaviour is because the console 
application is buffering text into a pipe instead of simply printing.
Apprently, in C++, setting the following will correct this issue:
setvbuf(stdout, NULL, _IONBF, 0);
setvbuf(stderr, NULL, _IONBF, 0);

Reported by james2k2 on 2010-03-13 01:56:48

[gcode-importer]

Could you propose a patch with your proposed fix ?

Reported by fodevaux on 2010-04-08 18:30:08

• Status changed: Started

[gcode-importer]

Hi,
I tried modifying the source-code to include those lines of code, but it failed. 
Maybe it was where I put them, I'm not sure. Instead, I have re-written all the 
print statements that I need to acertain a status of how the encoding is going. When

run in a console, it's exactly the same as before, just my app can now see what is

being output.

Reported by james2k2 on 2010-05-26 22:44:30

[gcode-importer]

I tried image_to_j2k.exe with the current svn code, and the console (MSYS or windows
console, win xp) output is the same than linux:

torri@CARO-50BC2B3960 ~/svnroot/openjpeg/build/libopenjpeg/.libs
$ ../../codec/.libs/image_to_j2k.exe -i ~/ebuilder2.png -o ebuilder.j2k

[INFO] tile number 1 / 1

(there is a pause, then)

[INFO] - tile encoded in 1.145806 s
Generated outfile ebuilder.j2k

maybe the OP should verify again with at least openjpeg 1.4

Reported by vincent.torri on 2011-03-04 22:59:08

[gcode-importer]

Sorry it's been a while. I will give OpenJPEG 1.4 a go since I am now also rewriting
my app from scratch with VB.NET 2008.

A fresh start can always help.

Thanks for your input.

Reported by james2k2 on 2011-07-09 12:08:24

[gcode-importer]

Hello again.

I have now tried v1.4 and still the same issue. I found the old forum posts I made
regarding this issue as I initially thought it was my app at fault. I have since rewrote
my app and the same applies. I fixed it by simply changing the fprintf statements in
the source for image_to_j2k to printf. Is this something you could do by default, or
will I need to modify each version myself?

Many thanks

Reported by james2k2 on 2011-07-11 11:40:01

[gcode-importer]

one could maybe ad an fflush in the definition of the callbacks. But it adds overhead
and there can be problems if one use get() just after for example

Reported by vincent.torri on 2011-07-28 06:05:11

[gcode-importer]

Hi James,

Concerning the "fprintf(stdout, ...)", they are strictly equivalent to "printf(...)"
so renaming them should not change anything. Or am I wrong ?

Concerning the "fprintf(stderr, ...)", I'm not in favor of renaming them into "printf".
A better solution would be to redirect stderr to whatever you want, from your app.

Reported by detonin on 2011-08-09 10:44:08

[gcode-importer]

Reported by malaterre on 2012-02-10 10:37:08

[gcode-importer]

Reported by malaterre on 2014-02-26 09:03:49

• Labels added: Priority-Low
• Labels removed: Priority-Medium

[gcode-importer]

no update in years, closing issue. Re-open if you can provide more input.

Reported by malaterre on 2014-02-26 14:07:24

• Status changed: WontFix