Custom processing for JPEG (Tone curve, CA ...)

[toinech]

I also tried curves and found some strange things (see attached picture, 100% crop at right border of image):
- Some unprocessed vertical band at right side of image. Maybe, skippings of last 40 columns is too much.
The same things reported in russian forum user of S3IS, his image:

Here are the fixes for those columns and the deactivation of curve when RAW is activated.

[reyalp]

Looking at this code to reduce memory use, I noticed a couple things:

in curve_apply()

Code: [Select]

switch(conf.curve_enable) {
...
case 2:
case 3: // +1EV,  +2EV
if (drcurve_loaded) drcurve_apply( conf.curve_enable >> 1 );

the >> is useless since 10b >> 1 == 11b >> 1

perhaps &1 does what was intended ?

also

Code: C

1.                 f read(drcurve0, 1, 4*CURVE_SIZE*sizeof(unsigned short), fd); // load a set of 4 curves - only 2 are used
2.  

Any reason not to just load 2 ?

[toinech]

Looking at this code to reduce memory use, I noticed a couple things:

in curve_apply()

Code: [Select]

switch(conf.curve_enable) {
...
case 2:
case 3: // +1EV,  +2EV
if (drcurve_loaded) drcurve_apply( conf.curve_enable >> 1 );

the >> is useless since 10b >> 1 == 11b >> 1

perhaps &1 does what was intended ?

You are right. This was a leftover from some code that I experimented. That would explain why +2EV never get works for some user.

also

Code: C

1.                 f read(drcurve0, 1, 4*CURVE_SIZE*sizeof(unsigned short), fd); // load a set of 4 curves - only 2 are used
2.  

Any reason not to just load 2 ?

You are also right here - some left over code from some experimentation.

Thank you for your feed back. I am getting sloppy ...

[PhyrePhoX]

awrite, i guess reyalp is cleaning up the code... can't take long and he finds my messy loc, i should start hiding and renting a house in Hawa- erh, wouldnt make sense posting my hiding spot here, would it.

[reyalp]

Hrm:
raw.c 203

Code: [Select]

        finished();

        return (fd >= 0);
    }

#ifdef OPT_CURVES
    if (conf.curve_enable) curve_apply();
#endif
    return 0;

if raw is enabled, curve is not applied to jpeg ?

[toinech]

Hrm:
raw.c 203

Code: [Select]

        finished();

        return (fd >= 0);
    }

#ifdef OPT_CURVES
    if (conf.curve_enable) curve_apply();
#endif
    return 0;

if raw is enabled, curve is not applied to jpeg ?

Good point. I believe that you missed an early post that fixes this and other things.
http://chdk.setepontos.com/index.php/topic,932.msg24656.html#msg24656
I do not have access to SVN to update the code.

Thank you for taking time to cleanup the code.

Toine

[reyalp]

Thanks for that. I saw there were several posts, but wasn't clear which ones had been merged.

For the column fix, this processes the entire raw buffer, potentially modifying the border pixels, correct ? Any idea whether these becoming non-black affects canon processing ?

[toinech]

Thanks for that. I saw there were several posts, but wasn't clear which ones had been merged.

For the column fix, this processes the entire raw buffer, potentially modifying the border pixels, correct ? Any idea whether these becoming non-black affects canon processing ?

For the column fix, this processes the entire raw buffer as you indicated. It is possible that a non black border pixel may effect on the canon processing. I am not sure if sometimes the manufacturer uses the non exposed border to estimate sensor noise level and use it in some noise reduction algorithm.

I wrote the code (skipping columns) for my A610 which does not expose some of the last columns in the hope of saving some processing time. It looks like through other users that different cameras have different 'non exposed' areas.

Please note that the first 8 rows are not processed.

[toinech]

Posted the black hole fix for the luminance curves. No change for RGB.
Note the Green is now used as luminance instead of an average of G+B or G+R.
Hopefully, the DR curve should be more sensitive for the correction of blown out highlight.

Change made from trunk 725.

[orestes_mirayna]

<----New guy

I can't download the curvetools program for creating custom curve profiles. Any help would be very much appreciated. Thanks in advance.

[hotvedt]

I have lost the original zip-file, but here you have the CurvesEditor4k.exe

http://www.hot.ee/hotvedt/CurvesEditor4k.zip

-
Maybe some admin can check why i/we cannot access the attatchment in this post:
http://chdk.setepontos.com/index.php/topic,932.msg10927.html#msg10927

-
Edit: heres a link with the updated editor that works: http://chdk.setepontos.com/index.php/topic,932.msg17419.html#msg17419

[fe50]

It's here: CHDK wikia: Software # CHDK_related, forum dl link is http://chdk.setepontos.com/index.php?action=dlattach;topic=932.0;attach=1816 & is up.

It is also available from the CHDKsoft drop: http://drop.io/chdksoft/asset/curveupdate

[toinech]

SYSCURVES update attached.
Changed based on A610 response curves.
The previous version was incorrectly configured
Should help reduce significantly the high areas blown out.

[reyalp]

Added, svn 758

[hiker_jon]

Hi,

Anyone figure out how to modify curves for the SX10 12 bit raw?  I have looked at the code and it is a mystery to me.

Jon