Alaska Software Inc. - PNG Again
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AuthorTopic: PNG Again
Carlos a Beling PNG Again
on Sat, 28 Apr 2018 15:30:43 -0300
Good afternoon.
I read the messages about PNG in the NGs and it seems to me that the 
problem, if exists or not, was not clarifyed there.
I attached a example vey simple whre no images in ICO format (I did not 
tested others) can to be saved as PNG files.
Can anyone to say what is going wrong? Or if it is possible?

Fraternally
Beling


Png.zip
Jim LeeRe: PNG Again
on Sat, 28 Apr 2018 23:07:08 +0200
what do you want to do ?
why do you want to convert ICO to PNG ?
Carlos a Beling Re: PNG Again
on Wed, 02 May 2018 12:17:41 -0300
Good morning Jim.
Many thanks.
I need to mark the footer of an image with some information and rewrite 
it to disk many times.
As I can receive images in ICO, PNG, BMP (eventually JPG) format I think 
that the easyer way for working with the received image is to convert it 
to PNG format and work with all images in this format  (I think that PNG 
has not lossy of image and I can write in it).

In the testing program I noted two things:
1) when saving to disk the image generated in oIcon:getbitmap() and 
reading it back its transparency was not kept
2) it seems do not have any way to keep the received image transparency 
when writting it to a file.
3) oBitmap:savefile(... PNG) returns .f. and I do not know why.

Then, if possible, even for my documentation purpose, I would liketo 
know if it is possible to save the image as PNG or I will need to change 
the way of doing my routines of working with the images.

Fraternally
Beling

Em 28/04/2018 18:07, Jim Lee escreveu:
> what do you want to do ?
> why do you want to convert ICO to PNG ?
>
>
>
Jim LeeRe: PNG Again
on Wed, 02 May 2018 18:33:16 +0200
as i know ICO  PNG have transparency while Bitmap  JPG does not have it.
when using oIcon:getbitmap() transparency ist lost.

but than next Question : where do you want to use new Image ?

when used with Xbase++ you can try
oBitmap:transparentClr := GraMakeRGBColor({192,192,192})
Carlos a Beling Re: PNG Again
on Wed, 02 May 2018 17:05:02 -0300
Jim.
Many thanks again.

I want to use the image in windows with diferent background colors.

Debugging the test I observed:
1) you can not to change the BG color of a built image, but you can show 
it in diferent BG colors if the image's transparent color is set as its 
BG color when it is created
2) you do not loose nor can to change the transparent color of XbpIcon() 
saved as XbpBitmap() in memory
3) if you write to disk the XbpBitmap() loaded from XbpIco() its 
transparency is lost independing on what format you had saved
4) XbpBitmap() does not save PNG images (no errors are informed)
5) GraBitBlt() ignores transparent color
6) GraStringAt(), GraCaptionStr(), Graline() , Grabox() -not filling the 
BG-, and others iGra... functions ignore the FG color and, it seems, 
their BG is naturally transparent.
For testing this behaviour "on the fly' I create a XbpBitmap() and 
XbpPresSpace() and associate them during the debugging section(). May be 
you want to try it...

Fraternally
Beling



Em 02/05/2018 13:33, Jim Lee escreveu:
> as i know ICO  PNG have transparency while Bitmap  JPG does not have it.
> when using oIcon:getbitmap() transparency ist lost.
>
> but than next Question : where do you want to use new Image ?
>
> when used with Xbase++ you can try
> oBitmap:transparentClr := GraMakeRGBColor({192,192,192})
>
>
Jonathan LeemingRe: PNG Again
on Wed, 02 May 2018 17:18:56 -0600
On 5/2/2018 2:05 PM, Carlos a Beling wrote:
> Jim.
> Many thanks again.
> 
> I want to use the image in windows with diferent background colors.
> 
> Debugging the test I observed:
> 1) you can not to change the BG color of a built image, but you can show 
> it in diferent BG colors if the image's transparent color is set as its 
> BG color when it is created
> 2) you do not loose nor can to change the transparent color of XbpIcon() 
> saved as XbpBitmap() in memory
> 3) if you write to disk the XbpBitmap() loaded from XbpIco() its 
> transparency is lost independing on what format you had saved
> 4) XbpBitmap() does not save PNG images (no errors are informed)
> 5) GraBitBlt() ignores transparent color
> 6) GraStringAt(), GraCaptionStr(), Graline() , Grabox() -not filling the 
> BG-, and others iGra... functions ignore the FG color and, it seems, 
> their BG is naturally transparent.
> For testing this behaviour "on the fly' I create a XbpBitmap() and 
> XbpPresSpace() and associate them during the debugging section(). May be 
> you want to try it...
> 
> Fraternally
> Beling
> 
> 
> 
> Em 02/05/2018 13:33, Jim Lee escreveu:
>> as i know ICO  PNG have transparency while Bitmap  JPG does not have 
>> it.
>> when using oIcon:getbitmap() transparency ist lost.
>>
>> but than next Question : where do you want to use new Image ?
>>
>> when used with Xbase++ you can try
>> oBitmap:transparentClr := GraMakeRGBColor({192,192,192})
>>
>>
Hi Carlos,

First off let me say I am by no means an "expert" on graphics images.

However your problems brought to mind a notation in Clayton Jones Top 
Down documentation where he states...

"Xbase++  apparently has trouble with some PNG files.  I suspect it is 
due to variations in the way PNG files are constructed.  It seems to 
accept some and reject others.  Since it is intermittent and unreliable, 
I cannot continue to support PNG in Top-Down.  The source code has not 
been changed so you can try it, it might work."

I then checked Alaska's KB and found PDR ID: 6337 which has the 
description...

"If transparency is involved some Bitmaps are not saved properly in
the PNG file format."

and the solution...

"Save the file in a different file format such as JPEG or GIF"

Regards... Jonathan


jonathan.leeming@the-family-centre.com
Edmonton, Alberta, Canada
Carlos a Beling Re: PNG Again
on Thu, 03 May 2018 09:59:53 -0300
Hello Jonathan.
Good mornning.
Many thanks.
It was so hard to discover it.
Unfortunatelly the JPG format does not support transparency and, saving 
images with transparency, its BG color is lost and become unchangeable.
Fraternally
Beling

Em 02/05/2018 20:18, Jonathan Leeming escreveu:
> On 5/2/2018 2:05 PM, Carlos a Beling wrote:
>> Jim.
>> Many thanks again.
>>
>> I want to use the image in windows with diferent background colors.
>>
>> Debugging the test I observed:
>> 1) you can not to change the BG color of a built image, but you can
>> show it in diferent BG colors if the image's transparent color is set
>> as its BG color when it is created
>> 2) you do not loose nor can to change the transparent color of
>> XbpIcon() saved as XbpBitmap() in memory
>> 3) if you write to disk the XbpBitmap() loaded from XbpIco() its
>> transparency is lost independing on what format you had saved
>> 4) XbpBitmap() does not save PNG images (no errors are informed)
>> 5) GraBitBlt() ignores transparent color
>> 6) GraStringAt(), GraCaptionStr(), Graline() , Grabox() -not filling
>> the BG-, and others iGra... functions ignore the FG color and, it
>> seems, their BG is naturally transparent.
>> For testing this behaviour "on the fly' I create a XbpBitmap() and
>> XbpPresSpace() and associate them during the debugging section(). May
>> be you want to try it...
>>
>> Fraternally
>> Beling
>>
>>
>>
>> Em 02/05/2018 13:33, Jim Lee escreveu:
>>> as i know ICO  PNG have transparency while Bitmap  JPG does not
>>> have it.
>>> when using oIcon:getbitmap() transparency ist lost.
>>>
>>> but than next Question : where do you want to use new Image ?
>>>
>>> when used with Xbase++ you can try
>>> oBitmap:transparentClr := GraMakeRGBColor({192,192,192})
>>>
>>>
> Hi Carlos,
>
> First off let me say I am by no means an "expert" on graphics images.
>
> However your problems brought to mind a notation in Clayton Jones Top
> Down documentation where he states...
>
> "Xbase++  apparently has trouble with some PNG files.  I suspect it is
> due to variations in the way PNG files are constructed.  It seems to
> accept some and reject others.  Since it is intermittent and unreliable,
> I cannot continue to support PNG in Top-Down.  The source code has not
> been changed so you can try it, it might work."
>
> I then checked Alaska's KB and found PDR ID: 6337 which has the
> description...
>
> "If transparency is involved some Bitmaps are not saved properly in
> the PNG file format."
>
> and the solution...
>
> "Save the file in a different file format such as JPEG or GIF"
>
> Regards... Jonathan
>
>
Jose Antonio Diego KerejeRe: PNG Again
on Thu, 03 May 2018 11:03:45 +0200
Carlos:

In addition to what Jonathan says, if you need png images you can use this 
code.
It also allows you to standardize its size.

IF oBmp:saveFile( cFileName.png, , XBPBMP_FORMAT_PNG ) = FALSE

   oBmp:saveFile( cFileName.bmp, , XBPBMP_FORMAT_WIN3X )

   CreatePNG( cFileName.bmp, cFileName.png )
   ...


Regards. Diego

PS: This option is also valid to facilitate the direct conversion of graphic 
formats.


#define wiaFormatPNG  '{B96B3CAF-0728-11D3-9D7B-0000F81EF32E}'
#define wiaFormatBMP  '{B96B3CAB-0728-11D3-9D7B-0000F81EF32E}'
#define wiaFormatGIF  '{B96B3CB0-0728-11D3-9D7B-0000F81EF32E}'
#define wiaFormatJPEG '{B96B3CAE-0728-11D3-9D7B-0000F81EF32E}'
#define wiaFormatTIFF '{B96B3CB1-0728-11D3-9D7B-0000F81EF32E}'

*************************************************
PROCEDURE CreatePNG( cFile, cFileOut, nMaxWidth )
*************************************************
LOCAL oImg    := CreateObject( 'WIA.ImageFile'    )
LOCAL oIP     := CreateObject( 'WIA.ImageProcess' )
LOCAL oFilters:= oIP:Filters
LOCAL oPT1, oFilter

oImg:loadFile( cFile )

IF nMaxWidth # nil .AND. oImg:Width > nMaxWidth
   oPT1:= oIP:filterInfos( 'Scale' )
      oFilters:add( oPT1:filterID )
      oPT1:destroy()

   oFilter:= oIP:filters( 1 )
      oPT1:= oFilter:properties( 'MaximumWidth'        ) ; oPT1:Value := 
nMaxWidth                                        ; oPT1:destroy()
      oPT1:= oFilter:properties( 'MaximumHeight'       ) ; oPT1:Value := 
Round( nMaxWidth * oImg:Height / oImg:Width, 0 ) ; oPT1:destroy()
      oPT1:= oFilter:properties( 'PreserveAspectRatio' ) ; oPT1:Value := .F. 
; oPT1:destroy()
      oFilter:destroy()

   oPT1:= oIP:apply( oImg ) ; oImg:destroy()
   oImg:= oPT1

   oFilters:remove( 1 )
ENDIF

oPT1:= oIP:filterInfos( 'Convert' )
   oFilters:add( oPT1:filterID )
   oPT1:destroy()
   oFilters:destroy()

oFilter:= oIP:filters( 1 )
   oPT1:= oFilter:properties( 'FormatID' ) ; oPT1:Value := wiaFormatPNG ; 
oPT1:destroy()
   oFilter:destroy()

FErase( cFileOut )

oPT1:= oIP:Apply( oImg ) ; oPT1:SaveFile( cFileOut ) ; oPT1:destroy()

oImg:destroy()
oIP:destroy()
RETURN
Carlos a Beling Re: PNG Again
on Thu, 03 May 2018 10:09:17 -0300
Hello Diego.
Good morning.
Many thanks.
So easy and so hard to discover as you did.
Would it to be possible to save XbpBitmap() objects created "on fly" in 
files with PNG format?

Fraternally
Beling

Em 03/05/2018 06:03, Jose Antonio Diego Kereje escreveu:
> Carlos:
>
> In addition to what Jonathan says, if you need png images you can use
> this code.
> It also allows you to standardize its size.
>
> IF oBmp:saveFile( cFileName.png, , XBPBMP_FORMAT_PNG ) = FALSE
>
>    oBmp:saveFile( cFileName.bmp, , XBPBMP_FORMAT_WIN3X )
>
>    CreatePNG( cFileName.bmp, cFileName.png )
>    ...
>
>
> Regards. Diego
>
> PS: This option is also valid to facilitate the direct conversion of
> graphic formats.
>
>
> #define wiaFormatPNG  '{B96B3CAF-0728-11D3-9D7B-0000F81EF32E}'
> #define wiaFormatBMP  '{B96B3CAB-0728-11D3-9D7B-0000F81EF32E}'
> #define wiaFormatGIF  '{B96B3CB0-0728-11D3-9D7B-0000F81EF32E}'
> #define wiaFormatJPEG '{B96B3CAE-0728-11D3-9D7B-0000F81EF32E}'
> #define wiaFormatTIFF '{B96B3CB1-0728-11D3-9D7B-0000F81EF32E}'
>
> *************************************************
> PROCEDURE CreatePNG( cFile, cFileOut, nMaxWidth )
> *************************************************
> LOCAL oImg    := CreateObject( 'WIA.ImageFile'    )
> LOCAL oIP     := CreateObject( 'WIA.ImageProcess' )
> LOCAL oFilters:= oIP:Filters
> LOCAL oPT1, oFilter
>
> oImg:loadFile( cFile )
>
> IF nMaxWidth # nil .AND. oImg:Width > nMaxWidth
>    oPT1:= oIP:filterInfos( 'Scale' )
>       oFilters:add( oPT1:filterID )
>       oPT1:destroy()
>
>    oFilter:= oIP:filters( 1 )
>       oPT1:= oFilter:properties( 'MaximumWidth'        ) ; oPT1:Value :=
> nMaxWidth                                        ; oPT1:destroy()
>       oPT1:= oFilter:properties( 'MaximumHeight'       ) ; oPT1:Value :=
> Round( nMaxWidth * oImg:Height / oImg:Width, 0 ) ; oPT1:destroy()
>       oPT1:= oFilter:properties( 'PreserveAspectRatio' ) ; oPT1:Value :=
> .F. ; oPT1:destroy()
>       oFilter:destroy()
>
>    oPT1:= oIP:apply( oImg ) ; oImg:destroy()
>    oImg:= oPT1
>
>    oFilters:remove( 1 )
> ENDIF
>
> oPT1:= oIP:filterInfos( 'Convert' )
>    oFilters:add( oPT1:filterID )
>    oPT1:destroy()
>    oFilters:destroy()
>
> oFilter:= oIP:filters( 1 )
>    oPT1:= oFilter:properties( 'FormatID' ) ; oPT1:Value := wiaFormatPNG
> ; oPT1:destroy()
>    oFilter:destroy()
>
> FErase( cFileOut )
>
> oPT1:= oIP:Apply( oImg ) ; oPT1:SaveFile( cFileOut ) ; oPT1:destroy()
>
> oImg:destroy()
> oIP:destroy()
> RETURN
>
Jose Antonio Diego KerejeRe: PNG Again
on Thu, 03 May 2018 23:50:56 +0200
Carlos:

I modified your sample a bit to generate pngs and "simulate" the 
transparency. If I have some time at the weekend, I'll take a new look.

Regards. Diego


TesteIco.zip
Carlos a Beling Re: PNG Again
on Fri, 04 May 2018 11:03:05 -0300
Hello Diego.
Many thanks.
Very, very, very nice.
I will be expecting you to have a new look. Would it to be better than 
this one?

Fraternally
Beling

Em 03/05/2018 18:50, Jose Antonio Diego Kereje escreveu:
> Carlos:
>
> I modified your sample a bit to generate pngs and "simulate" the
> transparency. If I have some time at the weekend, I'll take a new look.
>
> Regards. Diego
Jim LeeRe: PNG Again
on Sat, 05 May 2018 03:32:55 +0200
hi,

again i have to ask what you want to to with Images ?
do you only want to convert Image or use it in you Xbase++ App ? 24bpp or 
32bpp Color ?

if you want to use those Image for Controls (XbParts) than you get Different 
Result when use Mainifest (yes) or not (no)

i use Windows Imagelist to hold, all type of Image, for my native Controls.
https://msdn.microsoft.com/en-us/library/windows/desktop/bb761389(v=vs.85).aspx
Xbase++ does have a CLASS ImageList (for XbpToolbar) but is using 
MsComCtl.OCX ...

what is transparency :
as i know real transparancy mean Alpha Channel with 32bpp Color using 
ILD_TRANSPARENT (0x01) to draw a Image.
other Way is to use to ILC_MASK with 2 Image where 1 is Monochrom (B/W). i 
guess that is what Diego does

have a look about 32bit Image here
https://www.codeproject.com/Articles/9142/Adding-and-using-bit-alphablended-images-and-ic#_articleTop

p.s. when using Imagelist you can get a single Image and write it as file in 
any Image Format
Carlos a Beling Re: PNG Again
on Tue, 08 May 2018 12:47:45 -0300
Hello Jim.
Good afternoon.
Sorry for the late response.
I do not want convert images. If needed I only want to save them to a 
file or to use its background color as transparency for to show them in 
diferents windows background colors.

I was very confused about transparency in Xbase++ and I found out after 
many tries:
1) XbpBitmap():loadFile() only loads transparency information fom files 
GIF and PNG
2) in XbpBitmap():setBuffer() you need to inform the image format and 
implicitly, the XbpBitmap():transparentClr
3) only XbpBtimap():draw() or XbpIcon():draw() can to process 
transparency colors in Xbase++ (GraBitBlt() can not)
4) the XbpBitmap():transparentClr may to be anyone
5) if I make XbpBitmap():transparentClr := 
XbpBitmap():getDefaultBgColor() the image's background is "shown" 
transparent for any image type loaded.
6) Xbase++ does not work fine with PNG images

The example posted by Mr Diego at this time is enought for me.
Again I thank very much to all you that helped me.

Fraternally
Beling


Em 04/05/2018 22:32, Jim Lee escreveu:
> hi,
>
> again i have to ask what you want to to with Images ?
> do you only want to convert Image or use it in you Xbase++ App ? 24bpp or
> 32bpp Color ?
>
> if you want to use those Image for Controls (XbParts) than you get Different
> Result when use Mainifest (yes) or not (no)
>
> i use Windows Imagelist to hold, all type of Image, for my native Controls.
> https://msdn.microsoft.com/en-us/library/windows/desktop/bb761389(v=vs.85).aspx
> Xbase++ does have a CLASS ImageList (for XbpToolbar) but is using
> MsComCtl.OCX ...
>
> what is transparency :
> as i know real transparancy mean Alpha Channel with 32bpp Color using
> ILD_TRANSPARENT (0x01) to draw a Image.
> other Way is to use to ILC_MASK with 2 Image where 1 is Monochrom (B/W). i
> guess that is what Diego does
>
> have a look about 32bit Image here
> https://www.codeproject.com/Articles/9142/Adding-and-using-bit-alphablended-images-and-ic#_articleTop
>
> p.s. when using Imagelist you can get a single Image and write it as file in
> any Image Format
>
>
Carlos a Beling Re: PNG Again
on Wed, 09 May 2018 09:45:53 -0300
Hello.
Good morning.
Me again.
I am finishing my work about PNG and I'd like to get these answers?

a) can I use the function DisablePNG() for all XbpBitmap()?
b) is only PNG images that needes to have its transparency corrected?
c) can I save as file any XbpBitmap() created "on fly" keeping its 
properties using the function CreatePNG()?

Fraternally
Beling