Legacy ImageMagick Discussions Archive

and the heic files linked come from iphone devices (picture taken by default from the iphone camera), so they are not quite uncommon, it's the standard ...

ooh yes sorry I mean 7.0.8.44 ...

>> Did IM ever find an RGB ICC profile in a YCbCr HEIC file

yes in 7.0.7.23 ...

thanks a lot @snibgo !

So as a conclusion, we can say :

1/ there is a regression in IM 6.0.8.44 as it's not possible anymore to find the ICC profile , so impossible anymore to convert the .heic file to jpg keeping the icc profile configuration (it's will be removed, but image stay in YCbCr color ...

@snibgo thanks a lot for this documentative answer! I still not understand one thing, how iphone devices (so quite a lot of users) can send image with YCbCr color space and sRGB color profile and as you say this is non-sense because an RGB profile can't be applied to YCbCr color space? but this work ...

@fmw42

So how to do (programmatically) with my picture (https://filebin.ca/4fy7yPEUfwga/picture.zip)
When I receive it in my server, when I do MagickGetImageColorspace I can see it's not sRGB (YCbCr here) but I see also that there is 1 ICC profile.
how to know if it's an sRGB icc profile or not ...

@snibgo

little question, when I want to convert any image with any kind of icc profiles to a sRGB icc profile do I always need to first convert the image to sRGBColorspace color space and then later apply the icc sRGB color profile ?

MagickTransformImageColorspace(sRGBColorspace ...

@snibgo

Ok I found it's was MagickTransformImageColorspace

so under 7.0.7.23 doing

NewMagickWand(..)
MagickReadImage(.. "myImage.heic" ..)
MagickSetImageFormat(.. "jpg" ..)
MagickGetImageProfiles(.. '*' ..) => found one icc profile
MagickTransformImageColorspace(sRGBColorspace ...

@snibgo: i Found it's MagickSetColorspace(). I did it but it's not help :(

under 7.0.7.23 :

NewMagickWand(..)
MagickReadImage(.. "myImage.heic" ..)
MagickSetImageFormat(.. "jpg" ..)
MagickGetImageProfiles(.. '*' ..) => found one icc profile
MagickSetColorspace(sRGBColorspace)
MagickProfileImage ...

@snibgo : "If you think your file is encoded with P3 colorspace"
I don't know actually, I receive the file from internet and work on it on the fly (it's a web server) :(
So I can only trust what IM say me, but here look like im is wrong (in 7.0.8.44) :(

also, do you know how to convert to sRGB ...

@snibgo yes convert picture_1788442403862513610_-77991839800696479_-50_-50.heic out.png look good on 7.0.8.44 the but ICC color profile get lost :(

Main problem is that 7.0.8.44 found no ICC color profile when there is one but 7.0.7.23 found one ICC color profile this why I say maybe it's a ...

exactly same problem for me here

under imagemagick 7.0.7.23 when i do :

NewMagickWand(..)
MagickReadImage(.. "myImage.heic" ..)
MagickSetImageFormat(.. "jpg" ..)
MagickGetImageProfiles(.. '*' ..)
=> then it's return an icc profile

under the last one (7.0.8.44) then then same command return NO icc profile :(
so it's a possible ...

Hello,

I have an .heic image (with come from an iOS device). How to convert it to sRGB ?
Before I was doing like this :

To convert to sRGB:
MagickProfileImage(Wand, 'icc', <sRGB2014.icc>);
then I immediately delete the sRGB profile to win space
MagickProfileImage(Wand, 'icc', nil);

but it's ...

problem is that if you don't do fine tuning you can easily fall in situation where imagemagick will work very slowly, using only one CPU, or worse swaping between all cpu making operation very slow

@snibgo but why in this way IM choose by default MAGICK_THREAD_LIMIT=8