ART crashes with some images when running function "RawImageSource::getAutoMatchedToneCurve"

[t.guillermin]

app crashes with some images when running function "RawImageSource::getAutoMatchedToneCurve" (histmatching.cc file).

....

CurveEvaluator eval(*source, *target);

size_t best = candidates.size();

double bestscore = RT_INFINITY;

for (size_t i = 0; i < candidates.size(); ++i) {

double score = eval(candidates[i]); // --> crash

...

After searching, the following lines produce the crash

int l = c.getVal(img_[y][x]) * 255.f;

++hist[l]; // --> l > 255 To avoid the crash,

I added this modification:

if (l < 256) ++hist[l];

But, this is not a good solution, the best would be for c.getVal(...) to return a value between 0 and 1.

‌

Congratulations again for your fantastic work

‌

[agriggio]

hi,

Thanks for reporting. Do you have an image you can share that triggers the bug?

[t.guillermin]

This is a OM--1 raw image that i found on the web.

I use LibRaw (https://github.com/LibRaw/LibRaw)..)

With “mem_image” software sample, the extraction is Ok

[agriggio]

I’m not sure the OM-1 is fully supported yet, it only comes in a unreleased version of libraw (not even the latest snapshot). Do you have another example where this crashes?

Note: this is most definitely a bug, but I’d like to understand a bit better when it happens…

[t.guillermin]

WeTransfer link: https://we.tl/t-M7PEvJ5bPt

[agriggio]

histmatching: avoid out of bounds array access

Fixes #244

→ <<cset c24396b8ab30>>