Re: Avoiding color transformations in PNG/UIImage/CGImage ops?

2017-11-17 Thread Rick Mann
> On Nov 17, 2017, at 14:03 , Vince DeMarco wrote: > > > >> On Nov 17, 2017, at 1:45 PM, Rick Mann wrote: >> >> >> >>> On Nov 17, 2017, at 13:36 , Vince DeMarco wrote: >>> >>> >>> On Nov 17, 2017, at 1:28 PM, Rick Mann wrote: Nope, I'm definitely looking at pixel data

Re: Avoiding color transformations in PNG/UIImage/CGImage ops?

2017-11-17 Thread Vince DeMarco
> On Nov 17, 2017, at 1:45 PM, Rick Mann wrote: > > > >> On Nov 17, 2017, at 13:36 , Vince DeMarco wrote: >> >> >> >>> On Nov 17, 2017, at 1:28 PM, Rick Mann wrote: >>> >>> Nope, I'm definitely looking at pixel data. But I'll try the generic color >>> space. I don't know how it chooses

Re: Avoiding color transformations in PNG/UIImage/CGImage ops?

2017-11-17 Thread Alex Zavatone
> On Nov 16, 2017, at 9:27 PM, Alex Zavatone wrote: > > Profile Name: sRGB IEC61966-2.1? Are you using CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); Or as you said, not setting one at all? You can check on a CGImageRef with CGColorSpaceRef colorSpace = CGImag

Re: Avoiding color transformations in PNG/UIImage/CGImage ops?

2017-11-17 Thread Alex Zavatone
> On Nov 17, 2017, at 3:45 PM, Rick Mann wrote: > > > >> On Nov 17, 2017, at 13:36 , Vince DeMarco wrote: >> >> >> >>> On Nov 17, 2017, at 1:28 PM, Rick Mann wrote: >>> >>> Nope, I'm definitely looking at pixel data. But I'll try the generic color >>> space. I don't know how it chooses

Re: Avoiding color transformations in PNG/UIImage/CGImage ops?

2017-11-17 Thread Rick Mann
> On Nov 17, 2017, at 13:36 , Vince DeMarco wrote: > > > >> On Nov 17, 2017, at 1:28 PM, Rick Mann wrote: >> >> Nope, I'm definitely looking at pixel data. But I'll try the generic color >> space. I don't know how it chooses device color space when it's created >> absent any particular di

Re: Avoiding color transformations in PNG/UIImage/CGImage ops?

2017-11-17 Thread Vince DeMarco
> On Nov 17, 2017, at 1:28 PM, Rick Mann wrote: > > Nope, I'm definitely looking at pixel data. But I'll try the generic color > space. I don't know how it chooses device color space when it's created > absent any particular display-associated context. Don't use the generic color space use s

Re: Avoiding color transformations in PNG/UIImage/CGImage ops?

2017-11-17 Thread Alex Zavatone
> On Nov 17, 2017, at 3:28 PM, Rick Mann wrote: > > Nope, I'm definitely looking at pixel data. But I'll try the generic color > space. I don't know how it chooses device color space when it's created > absent any particular display-associated context. > Rick, this reminds me of what I ran i

Re: Avoiding color transformations in PNG/UIImage/CGImage ops?

2017-11-17 Thread Rick Mann
Nope, I'm definitely looking at pixel data. But I'll try the generic color space. I don't know how it chooses device color space when it's created absent any particular display-associated context. > On Nov 17, 2017, at 06:54 , Steve Christensen wrote: > > It sounds like you're looking at imag

Re: Avoiding color transformations in PNG/UIImage/CGImage ops?

2017-11-17 Thread Steve Christensen
It sounds like you're looking at image file data rather than buffers of pixel data. If so then I wouldn't make the assumption that the encoded bytes in two PNG files will be identical for identical images. Depending on how flexible the file format is, then particular parts of the encoded image c