how to reduce PNG file size ?

[Zalman Lazkowicz]

Is it possible to reduce PNG file size? Thanks, Zal Lazkowicz

[thorstenlemke]

Hello,that depends on the content. Simple e-mail a sample file.Thorsten Is it possible to reduce PNG file size?Thanks,Zal Lazkowicz

[Tony Jackson]

>Is it possible to reduce PNG file size? Most file types shrink a little further if you then use Acrobat to convert them into pdf's. Reducing the number of colours (or greys) reduces the file size considerably. Reducing the number of pixels, of course, reduces the file size. Aligning you image, if it has lines in it, so that the lines are horizontal or vertical helps (png can then basically record the beginning and end and extrapolate, whereas a diagonal is more number-hungry to encode. Remove dust, clutter, any un-needed pixels. After that you have to start accepting loss. Afaik. Best, T. -- Tony Jackson, Devon, UK.

[Zalman Lazkowicz]

this is 11 mb. I need to make it less than 4 mb, without visible loss in quality.Thanks! On Apr 16, 2015, at 2:31 PM, Thorsten Lemke lemke@lemkesoft.de [gcmac] <gcmac@yahoogroups.com> wrote:Hello,that depends on the content. Simple e-mail a sample file.ThorstenIs it possible to reduce PNG file size?Thanks,Zal Lazkowicz

[Zalman Lazkowicz]

Thanks Tony!Zal On Apr 16, 2015, at 1:44 PM, Tony Jackson tony@you-me-and-us.com [gcmac] <gcmac@yahoogroups.com> wrote:>Is it possible to reduce PNG file size?Most file types shrink a little further if you then use Acrobat to convert them into pdf's.Reducing the number of colours (or greys) reduces the file size considerably.Reducing the number of pixels, of course, reduces the file size.Aligning you image, if it has lines in it, so that the lines are horizontal or vertical helps (png can then basically record the beginning and end and extrapolate, whereas a diagonal is more number-hungry to encode.Remove dust, clutter, any un-needed pixels.After that you have to start accepting loss.Afaik.Best, T.-- Tony Jackson,Devon, UK.

[thorstenlemke]

Attachments ear Zal,ah - so, I suggest to convert to JPG with a very high quality. You will have only small loss but a much smaller file.Thorsten this is 11 mb. I need to make it less than 4 mb, without visible loss in quality.Thanks!<Yosemite.png>On Apr 16, 2015, at 2:31 PM, Thorsten Lemke lemke@lemkesoft.de [gcmac] <gcmac@yahoogroups.com> wrote:Hello,that depends on the content. Simple e-mail a sample file.ThorstenIs it possible to reduce PNG file size?Thanks,Zal Lazkowicz

[Zalman Lazkowicz]

Thanks Thorsten, but I need this in PNG. There are some sites that do that, but it takes quite some time uploading.Thought maybe GC has something like that, sort of compressor. On Apr 16, 2015, at 3:17 PM, Thorsten Lemke lemke@lemkesoft.de [gcmac] <gcmac@yahoogroups.com> wrote:Dear Zal,ah - so, I suggest to convert to JPG with a very high quality. You will have only small loss but a much smaller file.Thorstenthis is 11 mb. I need to make it less than 4 mb, without visible loss in quality.Thanks!<Yosemite.png>On Apr 16, 2015, at 2:31 PM, Thorsten Lemke lemke@lemkesoft.de [gcmac] <gcmac@yahoogroups.com> wrote:Hello,that depends on the content. Simple e-mail a sample file.ThorstenIs it possible to reduce PNG file size?Thanks,Zal Lazkowicz

[thorstenlemke]

Hello,you can only try the lossy PNG save. But that will reduce to 256 colors.Or select as filter “Automatic” for the compression. This may save some bytes.Or just scale it down by factor 2.Thorsten Thanks Thorsten, but I need this in PNG. There are some sites that do that, but it takes quite some time uploading.Thought maybe GC has something like that, sort of compressor.

[Tony Jackson]

Attachments : Re: [gcmac] how to reduce PNG file size ? [1 Attachment] this is 11 mb. I need to make it less than 4 mb, without visible loss in quality. Thanks! The file has already been lossily compressed, probably jpeg. Here it is at 434 KB, just by dragging it into Acrobat Pro 7 (very old.) If the difference in quality is important, I've put a jpeg version at 2.3 MB, created in GC 5.9..  I'm sure you won't be able to see any difference, between this and the original. The resolution is 150 dpi, and the size is 18" x 12".  Is that intended? Best, T. -- Tony Jackson, Devon, UK.

[Tobias Jung]

Zalman Lazkowicz zlazkow@yahoo.com [gcmac] wrote (Thu, 16 Apr 2015 14:42:19 +0300): > this is 11 mb. I need to make it less than 4 mb, without visible loss in > quality. Without visible loss in quality, that should be impossible. For GC or any other tool. As Tony Jackson suggested, you can reduce the number of colours (that's one of the things that those online tools you're mentioning do). That'll result in a file of about 2 MB, but of course, that will be visible, though to a lesser degree than you might suspect. Kind regards, Tobias Jung