Paste image from clipboard : RGB becomes BGR on IOS 64 bits ?

[FabDev 8]

Hello,

 

In Delphi 11.3, why a pasted image from clipboard RGB becomes BGR on IOS 64 bits (16.5)  ?

 

This sample which paste a bitmap from clipboard is extracted from :

https://docwiki.embarcadero.com/CodeExamples/Alexandria/en/FMX.CopyPaste_Sample

https://github.com/Embarcadero/RADStudio11Demos/tree/main/Object Pascal/Multi-Device Samples/User Interface/CopyPaste

=> This demo has the same problem !

procedure TForm66.Button1Click(Sender: TObject);
var
  Bitmap:TBitmap;
  LStream:TMemoryStream;
  Svc: IFMXClipboardService;
  Value: TValue;
begin
  if TPlatformServices.Current.SupportsPlatformService(IFMXClipboardService, Svc) then
  begin
     Value := Svc.GetClipboard;
     if Value.IsType<TBitmapSurface> then
     begin
      ImageSRC.Bitmap.Assign(Value.AsType<TBitmapSurface>);
     end
     else showmessage('Clipboard not a bitmap');
  end;
end;

 

Work fine on Windows  32 or 64 bits, Android  64 bits and MacOS  64 bits

But on IOS  64 bits (16.5) image is pasted but RGB colors becomes BGR...

 

   is pasted to => 

 

 

 

Same with :

GlobalUseMetal := True;
GlobalUseSkia := True;

 

Full sample in attachment.

 

 

ImagePasteFromClipboardIOSRGBLost.zip

Edited June 23, 2023 by FabDev

[Rollo62 536]

Could this be related to 24Bit vs. 32Bit images ?

https://stackoverflow.com/questions/57143845/mtktextureloader-messes-png-rgb-vs-bgr-formats

https://developer.apple.com/documentation/accelerate/conversion

https://stackoverflow.com/questions/46886993/how-to-determine-whether-the-colour-format-is-rgb-or-bgr

https://developer.apple.com/documentation/coregraphics/cgcolorspacemodel?language=objc

 

[Anders Melander 1783]

I don't have time to look at the source but if the bitmap being pasted is a 16 or 32-bit BMP bitmap with BI_BITFIELDS encoding then the problem can be that Delphi's TBitmap doesn't really support the nuances of that format.

The BI_BITFIELDS format uses 3 (or 4, depending on the BMP version) mask values that specify the layout of the RGB channels in the pixel values and AFAIR TBitmap ignores the mask values and instead assumes a certain layout.

[Patrick PREMARTIN 72]

Thanks for having opened an issue, it will be easier to follow at https://quality.embarcadero.com/browse/RSP-41896

[Anders Melander 1783]

8 hours ago, Patrick PREMARTIN said:

Thanks for having opened an issue, it will be easier to follow at https://quality.embarcadero.com/browse/RSP-41896

The bitmap in that issue is a version 1 BMP in BI_RGB format so the problem I mentioned does not apply.

 

Issue RSP-37651 might be related. According to that issue, it's fixed in 11.2 but as far as I can tell from looking at the source in 11.2 it hasn't been fixed. At least not in the way suggested by the reporter.

[Dave Nottage 557]

47 minutes ago, Anders Melander said:

At least not in the way suggested by the reporter.

The fix in 11.2 is essentially the same as was suggested. The problem is that UIImageToBitmapSurface was not fixed, as opposed to UIImageToBitmap (directly below it), which was.

 

[FabDev 8]

The image provided in my sample is only to understand that happen. I don't check if all type a picture (png, jpeg etc..)  have this problem.

 

But it's a very easy to reproduce :

0) Take a photo

1) Select this photo (in photo app)

2) Copy this photo to the clipboard (with Share option in IOS)

3) Paste it in source app given or sample from Embarcadero "CopyPaste ".

=> RGB becomes BGR

I have updated my report https://quality.embarcadero.com/browse/RSP-41896

Edited June 27, 2023 by FabDev