is it possible to convert image types (GD2)

[dan glenn]

(PHP4.3.4) Is it possible to change an image that's in one type (jpg, gif,
png) into another type? Especially, I know I can read a gif with GD2, but I
really need to be able to save it as a png. Is that possible?

-dg

[Matthias Esken]

Re: is it possible to convert image types (GD2)

dan glenn schrieb:
[color=blue]
> (PHP4.3.4) Is it possible to change an image that's in one type (jpg, gif,
> png) into another type? Especially, I know I can read a gif with GD2, but I
> really need to be able to save it as a png. Is that possible?[/color]

Why don't you just have a look at the documentation?

http://www.php.net/manual/en/function.imagepng.php

Regards,
Matthias

[Andy Hassall]

Re: is it possible to convert image types (GD2)

On Sat, 19 Jun 2004 07:13:48 GMT, "dan glenn" <dan_danboy@yah oo.com> wrote:
[color=blue]
>(PHP4.3.4) Is it possible to change an image that's in one type (jpg, gif,
>png) into another type? Especially, I know I can read a gif with GD2, but I
>really need to be able to save it as a png. Is that possible?[/color]

Yes, it is.

--
Andy Hassall <andy@andyh.co. uk> / Space: disk usage analysis tool
http://www.andyh.co.uk / http://www.andyhsoftware.co.uk/space

[Chung Leong]

Re: is it possible to convert image types (GD2)

"dan glenn" <dan_danboy@yah oo.com> wrote in message
news:MIRAc.7495 8$Im3.18399@new ssvr29.news.pro digy.com...[color=blue]
> (PHP4.3.4) Is it possible to change an image that's in one type (jpg, gif,
> png) into another type? Especially, I know I can read a gif with GD2, but[/color]
I[color=blue]
> really need to be able to save it as a png. Is that possible?
>[/color]

You can convert gif into png or jpeg but no vice-versa. The imagepng() and
impagejpeg() will save the image into the respected format.

[dan glenn]

Re: is it possible to convert image types (GD2)


"Chung Leong" <chernyshevsky@ hotmail.com> wrote in message
news:xc2dnb2jIt uK00ndRVn-vg@comcast.com. ..[color=blue]
> "dan glenn" <dan_danboy@yah oo.com> wrote in message
> news:MIRAc.7495 8$Im3.18399@new ssvr29.news.pro digy.com...[color=green]
> > (PHP4.3.4) Is it possible to change an image that's in one type (jpg,[/color][/color]
gif,[color=blue][color=green]
> > png) into another type? Especially, I know I can read a gif with GD2,[/color][/color]
but[color=blue]
> I[color=green]
> > really need to be able to save it as a png. Is that possible?
> >[/color]
>
> You can convert gif into png or jpeg but no vice-versa. The imagepng() and
> impagejpeg() will save the image into the respected format.[/color]

OK - I'm now saving .gif's to .png's, but I note that I lose the
transparancy (if there is one) in doing so. How can I maintain the
transparancy in the PNG???

-dg

[Chung Leong]

Re: is it possible to convert image types (GD2)

"dan glenn" <dan_danboy@yah oo.com> wrote in message
news:UF2Bc.7556 9$1R7.72583@new ssvr29.news.pro digy.com...[color=blue]
>
> "Chung Leong" <chernyshevsky@ hotmail.com> wrote in message
> news:xc2dnb2jIt uK00ndRVn-vg@comcast.com. ..[color=green]
> > "dan glenn" <dan_danboy@yah oo.com> wrote in message
> > news:MIRAc.7495 8$Im3.18399@new ssvr29.news.pro digy.com...[color=darkred]
> > > (PHP4.3.4) Is it possible to change an image that's in one type (jpg,[/color][/color]
> gif,[color=green][color=darkred]
> > > png) into another type? Especially, I know I can read a gif with GD2,[/color][/color]
> but[color=green]
> > I[color=darkred]
> > > really need to be able to save it as a png. Is that possible?
> > >[/color]
> >
> > You can convert gif into png or jpeg but no vice-versa. The imagepng()[/color][/color]
and[color=blue][color=green]
> > impagejpeg() will save the image into the respected format.[/color]
>
> OK - I'm now saving .gif's to .png's, but I note that I lose the
> transparancy (if there is one) in doing so. How can I maintain the
> transparancy in the PNG???
>[/color]

Hmmm, I just tried it and it works correctly. I'm using 4.3.6. Maybe GD is
saving the PNG with alpha-channel info (which IE doesn't support) instead of
single color transparency. View the image in Netscape or open it with
Photoshop and see if transparency is there.

[dan glenn]

Re: is it possible to convert image types (GD2)


"Chung Leong" <chernyshevsky@ hotmail.com> wrote in message
news:ie2dnQO1r4 AZRkndRVn-gg@comcast.com. ..[color=blue]
> "dan glenn" <dan_danboy@yah oo.com> wrote in message
> news:UF2Bc.7556 9$1R7.72583@new ssvr29.news.pro digy.com...[color=green]
> >
> > "Chung Leong" <chernyshevsky@ hotmail.com> wrote in message
> > news:xc2dnb2jIt uK00ndRVn-vg@comcast.com. ..[color=darkred]
> > > "dan glenn" <dan_danboy@yah oo.com> wrote in message
> > > news:MIRAc.7495 8$Im3.18399@new ssvr29.news.pro digy.com...
> > > > (PHP4.3.4) Is it possible to change an image that's in one type[/color][/color][/color]
(jpg,[color=blue][color=green]
> > gif,[color=darkred]
> > > > png) into another type? Especially, I know I can read a gif with[/color][/color][/color]
GD2,[color=blue][color=green]
> > but[color=darkred]
> > > I
> > > > really need to be able to save it as a png. Is that possible?
> > > >
> > >
> > > You can convert gif into png or jpeg but no vice-versa. The imagepng()[/color][/color]
> and[color=green][color=darkred]
> > > impagejpeg() will save the image into the respected format.[/color]
> >
> > OK - I'm now saving .gif's to .png's, but I note that I lose the
> > transparancy (if there is one) in doing so. How can I maintain the
> > transparancy in the PNG???
> >[/color]
>
> Hmmm, I just tried it and it works correctly. I'm using 4.3.6. Maybe GD is
> saving the PNG with alpha-channel info (which IE doesn't support) instead[/color]
of[color=blue]
> single color transparency. View the image in Netscape or open it with
> Photoshop and see if transparency is there.[/color]

Yes, you're right - the transparency is there. It was just IE. Gad. OK - is
there a way I can make imagepng() save the PNG as a palette-based (8-bit,
256-color) single-color transparancy? (These will work in IE, as they don't
use the alpha channel)

[R. Rajesh Jeba Anbiah]

Re: is it possible to convert image types (GD2)

"dan glenn" <dan_danboy@yah oo.com> wrote in message news:<RF7Bc.216 9$Re2.266@newss vr25.news.prodi gy.com>...
<snip[color=blue][color=green]
> > Hmmm, I just tried it and it works correctly. I'm using 4.3.6. Maybe GD is
> > saving the PNG with alpha-channel info (which IE doesn't support) instead[/color]
> of[color=green]
> > single color transparency. View the image in Netscape or open it with
> > Photoshop and see if transparency is there.[/color]
>
> Yes, you're right - the transparency is there. It was just IE. Gad. OK - is
> there a way I can make imagepng() save the PNG as a palette-based (8-bit,
> 256-color) single-color transparancy? (These will work in IE, as they don't
> use the alpha channel)[/color]

You may be interested in phpSt.Justin's wonderful article on the
subject <http://www.koivi.com/ie-png-transparency/>

--
| Just another PHP saint |
Email: rrjanbiah-at-Y!com